The following articles are taken from the MC aktiv publication and curated by Buidling Chemical Supplies Ltd. Content contained is therefore the property of MC-Bauchemie Müller GmbH & Co. KG.
The following articles are taken from the MC aktiv publication and curated by Buidling Chemical Supplies Ltd. Content contained is therefore the property of MC-Bauchemie Müller GmbH & Co. KG.
If you visit Nuremberg you instantly notice its castle. Immediately afterwards, you will encounter the second, obvious landmark of the city: The housing estate "Norikus" at the Wohrder See. With 1,300 units, it is the largest estate in Bavaria.
After 32 years nothing is left of the "charm of the 70s": The outer facades of the tower blocks, that are up to 80 m high, are weather-beaten. Together with some of the balconies it has to be refurbished as soon as possible. The costs are estimated to reach around 950,000 Euros. From 2004 until 2005 around 460 flats with a total façade surface of approx. 20,000 square metres are planned to be refurbished, followed by the external surface of a further 260 units.
The project planning was assigned to the specialist Sven Thole. The Nuremberg architect explains the necessary work on a specifically created model: The task requires the cleaning of the facades, the reinforcement of the fibre-cement slabs and improvement to the appearance using a durable coating with a good self-cleaning properties. At the same time, the visual character of the residence must remain unchanged. The new coating will be dark grey and opaque white. Furthermore, damaged concrete on the balconies and ceilings will be repaired and new surface coatings applied to the ceilings . The main contractor is the BVR Bau-Sanierungs GmbH from Nuremberg and the paintwork is carried out by the company Hertel from Stein.
MC has been participating in the project since June 2003. Some of the fibre-cement slabs were taken to the MC laboratory in Bottrop for experiments and coating with different base colours. From the tests the best product proved to be MC-DUR 1177 WV-A. For the coating of ceilings it was decided on Betonflair WG and WS. In August 2003, the material control institute Clausthai-Zellerfeld approved the required adhesive strength and diffusion by certifying it. The first trial project- the refurbishment of a unit on the estate damaged by fire – was carried out by the architect Sven Thole with MC's products and showed good results.
In April 2004, the actual refurbishment work for MC commenced. At the beginning, the painting of the fibre-cement slabs caused problems as the original dark colour had to be covered with a white coat. In this case, the opaque colour MC-DUR 1177 WV-A due to its insufficient film build was not suitable. After having changed to MC-DUR 1177 WEC as a base colour and painting twice with Betonflair WS in white, the work could be continued to everyone's satisfaction and on schedule.
Thanks to excellent preparation, the correct choice of products and good collaboration between the architect, the contractors and MC, the "Norikus" estate is gradually assuming its former impressive appearance.
Bridges have always been categorised as 'extremely demanding and high-capacity engineering structures'. Increasing traffic and increased aggressive environmental impacts inflict permanently high stress levels on the structure. During the service life ever greater damage and deterioration is inflicted. Technically sophisticated materials and system solutions are then required.
Between Bad Neuenahr and Sinzig, the longest bridge on the A61, the Ahrtalbrli• eke, crosses the Ahr Valley. 1,500m long and with 50m high concrete piers and concrete hollow box construction, the bridge dominates the valley landscape. After having been in use for over 30 years and following a routine inspection, the Autobahn Agency Montabaur decided extensive repair measures were required for this bridge.
Schachtbau Nordhausen GmbH was awarded the contract, an established company with extensive experience in bridge and civil engineering. Work started in August 2006 and completion is anticipated for March 2009.
Specification includes the repair of the underside elevations and the substructures. This incorporates the partial concrete repair and reprofiling of the 22 pairs of columns and column heads and coating the underside with a final surface protection coat.
For the column heads polymer modified cement mortar Nafufill GTS was applied by dry spray technique. Partial voids on the underside and substructures were reprofiled with Nafufill KM 250. This PCC concrete substitute fulfils all the requirements that are necessary for the repair of traffic structures. Nafufill KM 250, as an accredited M3-mortar, is structural, non-flammable and can demonstrate the reinstatement of fire-resistance category F90 - all aspects that mean additional safety.
The restoration of the corrosion protection of the reinforcement steel was performed using the mineral corrosion protection systems Zentrifix KMH or Colusal MK, depending on the choice of repair mortar.
To protect from the further detrimental effects of usage and weather, after the reprofiling works had been completed, the entire concrete area (approx. 100,000 m2} was coated with the surface protection system Nafufill KM 110 and Nafufill BS.
The location and height of the structure (high wind movement} and the steady advance of the movable scaffolding rendered the application of a conventional coating system impossible. But by selecting PCC fine filler Nafufill KM 110 the final coating of Nafufill BS could be applied after one hour.
Approximately ten kilometres from Utrecht in the Netherlands lies Beverweerd Castle. Originally, there was only a medieval, rectangular residential tower, probably built in the latter part of the 13th century. To this day this tower is still the core of this historic building.
During the course of the centuries, however, Beverweerd report was extended with further towers and a connecting wing to form the castle complex that exists today. Between 1835 and 1862 the complex was elaborately renovated in a neo-gothic style and the medieval appearance changed to a conservative country estate.
Following an eventful history Beverweerd stood empty for several years until it was acquired by the Philadelphia Vegetarian Centre in September 2006. The trust offers a unique centre for those who are strict vegetarians and over 60. Surrounded by a beautiful landscape the residents find tranquillity and recuperation. To this end 60 to 80 rooms are being built here. Further utility areas, such as offices, gastronomical and cultural facilities are still being considered.
Prior to the conversion of the complex extensive renovation was planned for the listed building; a task that requires experience and professional expertise as well as well-matched materials and technologies in order to permanently preserve the fabric of the building.
First of all, a detailed damage report was compiled in order to determine which materials and systems to use. Over the centuries, rising damp and weather influences had resulted in heavy salt exposure and efflorescence in the 1.5m thick brickwork exterior walls. In these rather difficult conditions normal renders, and long-term repair mortar systems, tend to fail.
Van Hoogvest, the Utrecht based architects contracted to do the works selected, the Dutch construction materials company Strikolith B.V., opted for the tried-and tested anti-moisture render, Excellent. This material with outstanding technical properties has successfully been used for the repair of historic buildings for over 14 years and was taken over by MC this year. The ready-mixed mortar possesses a structure that is open to diffusion. Special additives incorporated in the mortar impart a unique pore geometry that brings moisture in the brick-work to the surface. Damaging salts are transported along with the moisture and are thus no longer deposited with the mortar, where they could potentially cause damage. This pore geometry in combination with the high lime content of the non-hyrdrophobing mortar enables an evaporation performance that is 15 times higher than that of standard repair mortars.
Frank Kibner, a former employee at Scholz and now MC expert advisor for Excellent, advised the executing companies in the use of the anti-moisture mortar. The mortar was applied in four layers on the outside. First any loose particles were removed before the first layer was applied as a preliminary spray mortar, applied directly onto the damp brickwork. This was followed by two machine-applied white render layers. Finally, a pigmented fine render was applied. Overall, once all layers had been applied, the mortar was 4cm thick. Thanks to the short curing times the entire working process would be optimised.
The extensive renovation measures at the castle complex are being carried out in three stages: from December 2007 until June 2008 the north side and west side were rendered in full on the outside, plus the roof was extended. The works on the south and east side are to be completed by the end of 2008. For 2009 extensive works are planned on the basement and on the interior. Renovations are expected to be completed by August 2009.
On February 1, 2008 MC took over the product areas tile adhesives, joint mortar from the corporate group Harold Scholz GmbH & Co. KG, based in Recklinghausen, Germany, and is continuing both product portfolio and existing customer relations.
The ready-mixed mortar range has been integrated into the Oxal distribution of MC-Bauchemie. In future, especially the anti-moisture render Exzellent shall be marketed more forcefully, which has an excellent track record in the renovation of important historic projects.
The tile adhesive and joint mortar range is sold through MC’s affiliate company, Botament. Particular attention is being paid to the market development of the novel mineral-based joint SUPAX protect.
The repair of hydro-power stations is a current topic right now, given that it is a way of producing energy that is saving precious resources and is environmentally friendly. The "Volga-Rhine" project for instance was conceived in the year 2000 - a German-Russian joint venture funded by the German Government and the European Union. One of the project's main aims is to develop powerful repair mortars and concretes for water structures. Due to its relevant international experience and ground-breaking product solutions MC has been chosen as the industry partner in the construction chemicals sector to participate in the project.
New building materials and repair methods that fit this purpose were researched studying the example of the Volga hydropower station "Wolzhskaja" which has been in operation for over 50 years. Involved in the project on behalf of the German side were besides MC, scientists of the Institute for Solid Construction and Building Materials Technology (lfMB) from Karlsruhe University under the helm of Prof. Dr. Harald S. Muller and from the alliance of SMP lngenieure im Bauwesen GmbH, also based in Karlsruhe. On top of MC being able to boast of many years' experience in concrete technology, the company had the further advantage of having its own production location in Russia.
The power station, north of the former city of Stalingrad - nowadays called Volgograd - was put into operation in 1958. With an output of 2,563 megawatts of electricity it was then the largest power plant in the world. Even today the gigantic structure with its 22 turbines and 664m long power house is still impressive. During the course of its 50 years in operation over half a billion kilowatts were fed into the Russian high-voltage grid. However, the non-stop operation of the plant shows the ravages of time, relentlessly eating away at the huge weir systems.
The main problem of the state run power plant operator are the enormous changes in temperature that the region is prone to: in its hot summers temperatures regularly reach up to 40°C, while in the winter the thermometer may fall to as low as -35°C. The high freeze-thaw loading and the use of de-icing agents have over the years resulted in spalling of the concrete and in corrosion in the reinforcement. Cracks in the concrete structure cause water penetration and soaking, which in turn cause further damage under the action of ice. "In some areas defects had to also be removed using the underwater concrete method" explained Eugen Kleen during a broadcast of Zeitzeichen", a German radio programme from Westdeutscher Rundfunk. Together with concrete technologist Dirk Wisniewski, the Head of R&D Mineral Building Substances and Concrete Admixtures is looking after the project on behalf of MC.
During the repair works the involved parties were confronted with two challenges: on one hand they required modified, novel building materials to ensure a high concrete quality, on the other they needed repair methods that would allow implementing all measures without stopping the plant's operation.
Based on tests carried out at the site and in the lab repair concepts that were tailored to the particular problem scenarios were developed. In this instance the practical knowhow of the industrial company and the scientific-technical expertise of the research institute were brought to work together to perfection. The task further required the modification and development of new building materials. To this end numerous laboratory and field tests with simulated realistic applications, plus application technological and visual tests were carried out on test samples. These were meant to provide evidence of sufficient processability and stability, a high resistance against frost and wear and tear, as well as a high water-tightness and sufficient adhesive tensile strength. Further key aspects were the training of personnel involved in the repair works, the scientific-technical assistance onsite and developing a quality assurance guidebook as a basis for future maintenance.
During the course of the project a close cooperation between German and Russian scientists, project partners and authorities, ensued. This international connectedness turned out to be a warrant for the successful completion of these demanding repair measures. The translation of the newly developed technologies into practice within the hydro energy sector now opens up new perspective globally.
Concrete repair and surface protection of power plant cooling towers require specialist know-how on the side of the executing contractor. In such a case the challenge is to thoroughly repair large areas - sometimes at great heights - and to give protection for further operational use that will last several decades. To this end the applicator has to be able to rely 100% on the materials that are being used.
At present, Eastern Europe in particular, has numerous power plants that are in need of repair, for instance in the small Romanian town of lernut, situated about 100 km north of Sibiu. The gas power plant in lernut, which feeds electricity into the network during peak periods, consists of seven interconnected cooling towers that have been in operation since 1966.
After a little less than 40 years of use the building structure and the exterior concrete shell of the cooling towers was in need of repair. Especially in the uppermost areas the escaping water vapour had caused significant frost and de-icing damage. Low concrete cover had further aided this process of deterioration. Based on the expertise of the Institute for Construction Mechanics of the Polytechnic in Cluj Napoca the company Energoproject, based in Bucharest which specialises in power plants, developed a bespoke repair concept. In April 2008 the six months long repair works commenced.
Based on its many years of international experience in the area of repair and coating of cooling towers, MC was awarded the contract as expert consultant and as supplier for the entire concrete repair and surface protection systems. Advice and support onsite was provided by Alexandra Pumnut and Julian Boian, sales managers of MC Romania.
The repair works in lernut started with the preparation of the concrete shell: an eighth of the surface had to be removed. Then the area was grit blasted and primed with Zentrifix KMH. This mineral coat serves as a bonding course and as corrosion protection for the exposed reinforcement. Nafufill KM 250, a polymer modified spray-able structural repair mortar was used for the re-profiling of the concrete surface. The entire concrete repair was carried out from retractable scaffolding for which the concrete shell was divided into 14 vertical sections of 6m width each.
In the second stage the remaining areas were primed with Betonflair Uniprimer. Then the whole area was coated with the crack-bridging, pigmented surface protection system EmceColor-flex, which can be produced in any desired colour to suit individual customer requirements and ensures a smooth design that is free from contamination and dirt pick-up.
For the top edge the operator selected RAL 3000 as a signal paint and for the remainder of the concrete shell the colour white. EmceColor-flex which can be rolled or sprayed was applied in three layers by professional abseilers that lower themselves down from the top edge via a rope system.
Meanwhile lernut's cooling towers, coated in gleaming white paint, have featured nationwide in the Romanian media, being part of reports on the nation's energy situation.
Many access shafts in the sewer system are damaged and must be repaired as a matter of urgency. The innovative technology of the MRT system, combined with MC-Bauchemie's ombran range of products, considerably simplifies and speeds up the repair of shafts.
Sewer systems are designed to provide a secure method of transporting wastewater to the sewage treatment plants (STPs). Shafts, or manholes, serve as ventilation and access points. The number of shafts in Western Europe is in the region of 50 to 60 million. Ten million of these are located in Germany alone. On the basis of previous inspections, it is estimated that 10 to 20% need repair and this figure is increasing.
Freeze/thaw cycles, de-icing salts, biogenic sulphuric acid corrosion are the chemical inspired attacks. In addition there are the dynamic stresses and strains due to increasing road traffic. All these factors and the aggressive nature of sewage itself are responsible for the damage to sewer pipes and shafts. As a result, leaks in the sewer system overload the STPs due to infiltration of the groundwater. In addition, sewage which is further contaminated with harmful substances can enter the soil through ex-filtration and harm the soil and groundwater. Against this backdrop, repairing damaged access shafts and sewers is essential.
Until recently, laborious repair works have normally been carried out manually in restricted spaces. To comply with the extensive requirements of national and international Health & Safety legislation the task becomes even more difficult, time consuming and expensive. The automation of surface preparation and the subsequent coating works offers considerable advantages. HOT Hochdruck Dosier Technik GmbH and MC set themselves this challenge and developed the innovative MRT system (Manhole Rehabilitation Technology). It is made up of three basic components, which make manual work superfluous: a water and grit blasting unit, an automated spinning unit and a control unit.
Because the success of any repair depends on the substrate preparation, the blasting unit is used at the outset of the work. This is a remote controlled water and grit blasting unit, which rotates around the shaft axis and works with a pressure of up to 500 bar. It is securely centred in the shaft by vibration absorbers so that deviation is prevented. The integrated channel monitoring system provides controlled removal of grit and debris.
The repair mortar for coating the shaft is applied by the automated spinning unit, which is the core of the system. After reading the depth of the shaft in the control unit, the mortar is spun on to the area in need of coating with a high degree of compaction and free from pores and voids. By constantly varying the application rate to compensate for varying substrate profiles the specified thickness is maintained. Areas near the grappler (suspension points) are prone to not being coated adequately (shadows). Shadows are avoided by independent reversing of rotation at the reversal points. The overall time saving achieved with the MRT system when compared with traditional manual can be up to 80%.
The material used by the spinning unit is MC-Bauchemie's ombran MHP-SP. This mortar can be pumped with standard spiral pumps that are normally used for coarse mortar. It is therefore possible to coat large surfaces economically and rapidly. Using the "Dynamic SynCristallisation" (DySC®), a high chemical resistance of the mortar is achieved. With the DySC® technology, ombran MHP-SP's binding agent matrix is further compressed and reinforced. By using latent hydraulic and pozzolanic materials, a structure with the most dense sphere packing is achieved. As a result, porosities are reduced and the pore radius distribution is optimised. By combining the MRT system with ombran MHP-SP, extremely economical repairs and long lasting protection of shafts are achieved.
In light of the sometimes devastating tunnel fires, such as the one in the Gotthard tunnel in 2001, structural fire protection of tunnel structures has increasingly gained in significance in the last years. To protect the concrete and reinforcement from fire, fire-resistant mortar systems, among other things, are being used. Nafufill KM 250 has been proven to be a PCC concrete replacement which can be used universally in concrete repair and construction. It is now also proving that it can fulfil the highest demands of structural fire protection for tunnels.
When it comes to fire behaviour in structures, there are two fundamental areas: buildings and tunnels. The standard time/temperature curve (ETK), which is known globally as the ISO 834, was established for fi res in buildings. It simulates the temperature development, related to time, from the start of the fire through to a fully developed fire. According to the curve, a 90-minute hostile fire, for example, reaches a temperature of almost 1,OOOO°C. The curve ends after 180 minutes with a temperature of 1,090°C. of vehicle that is the basis of the fire or potential source of the fire. Against this background, different tunnel fi re curves were designed, in which the maximum temperature of the fire is revised, depending on the sequence of events and type of vehicle. All fire curves have in common that they take into account the quicker heating in the tunnel and increase considerably more steeply than the standard time/ temperature curve. Accordingly, in almost all scenarios, 1,000° (is exceeded after just a few minutes.
In tunnels, on the other hand, other laws apply. In comparison to buildings, a tunnel fire occurs in a closed space, in which heat cannot escape easily. The temperature load is correspondingly high. In addition, the thermal load cannot be definitively determined as it depends on the type of vehicle that is the basis of the fire or potential source of the fire.
Against this background, different tunnel fire curves were deisgned, in which the maximum temperature of the fire is revised, depending on the sequence of events and type of vehicle. All fire curves have in common that they take into account the quicker heating in the tunnel and increase considerably more steeply than the standard time/temperature curve. Accordingly, in almost all scenarios, 1,000ºC is exceeded after just a few minutes.
This rapid temperature increase has a negative effect on the concrete construction of the tunnel structure when there is a fire. The water, which is bound into the concrete, evaporates and expands. If this vapour pressure cannot be accommodated, explosion-like blistering occurs on the concrete that can reach the reinforcement core. If this is exposed, the heat can then have a direct effect on the steel. The consequences are distortion of the reinforcement core and a reduction of its rigidity, which endangers the entire structural integrity of the structure.
For this reason, the concrete and reinforcement must be protected from major hearing to create structural fire protection in tunnels. Nafufill KM 250 is currently the only PCC concrete replacement system available, which can be used in nearly all areas of concrete maintenance and can also fulfil fire protection requirements applicable to structural engineering, residential building and structural fire protection in tunnel structures. As a result, Nafufill KM 250, which has been tried-and-tested for years, is now virtually universally usable.
The fire resistance in accordance with the standard time/temperature curve for structural engineering and the tunnel fire curves as per ZTV-ING and the guidelines of the Federal Railway Authority (EBA) has already been proven for the plastic-modified cement mortar. Now, the maintenance system also fulfils the requirements of the Dutch Rijkswaterstaat (RWS) for building materials for structural fire protection in tunnel construction. This inspection, which is the strictest in Europe, was carried out in the laboratory of the Hagerbach Test Gallery in the Swiss town of Flums Hochwiese in the canton of St. Gallen.
The RWS fire curve was designed for road and rail tunnels, through which dangerous goods are transported. The fire of a fuel tanker, loaded with 50m3 of petrol, was taken as the basis. After just five minutes, a temperature of 1,200°C is achieved, which increases during the two-hour fire to 1,350°C to sink back to 1,200°C at the end.
Two reinforced concrete slabs were used for the laboratory trial. These slabs were given a 60mm layer of Nafufill KM 250. After integration in a special fire oven, Nafufill KM 250 was exposed to the temperatures described above. The fire protection system must not exhibit any blistering and had to maintain sufficient thermal insulation of the concrete and reinforcement core over the entire period.
Nafufill KM 250 passed this fire trial with the best results. The building material showed no impairments in the adhesion after considerable fire exposure and the complete coating profile remained intact. There was also no blistering to be seen on the concrete. In addition, the temperatures taken on the concrete test specimen during the fire investigation were convincing. The RWS stipulates that no more than 380°C can occur on the concrete surface, the so-called interface. However, a maximum of 267ºC was measured. In addition, the temperature must not rise over 250°C in a 25 mm depth beneath the interface. However, a rise of just 112°C was recorded. After this successful trial, Nafufill KM 250 can now also be used in numerous applications in the field of fire protection. The proven thermal isolation effect of the building material fulfils the structural fire protection in terms of the European tunnel fire curves. At the same time, the plastic-modified cement mortar is the first PCC concrete replacement, which can be used for the fire protection reinforcement of tunnel structures.
Every structure is prone to wear-and-tear over time. Depending on the quality of workmanship, service duration and intensity, weather impact or damages, sooner or later repairs are inevitable. In such cases it is not unusual that application conditions that existed at the time of construction are no longer given. This applies in particular to maritime structures that are permanently immersed in water. For this scenario MC-Bauchemie has developed an innovative solution that ensures applications are fast and reliable.
Repair works to parts of structures that are permanently underwater once in operation, and which cannot be dried even for a short period of time, prove to be particularly challenging. This applies not just to moles, piers and sluice gates in coastal regions, but also to inland waterways. Add to this paved river embankments, canal embankments and lakeshores, dams, pipelines, hydropower and tidal power stations as well as floating docks, oil platforms and other offshore installations such as lighthouses and wind power stations. This means there is a significant number of structures where regular repair measures, including sealing, repairing, bonding, anchoring, fastening or supporting, need to be performed below water.
Special pre-conditions in terms of application must be met to achieve a professional underwater repair, which can only be realised by highly specialised diving companies. The demanding and costly works must be carried out by professional divers that have experience in mixing and applying specialist repair materials.
A special niche sector has established itself, with Spanish, Portuguese and Dutch companies being in pole position. In Spain alone, 20 companies deal exclusively in underwater repairs, going down to a depth of 100m. Their main tasks include sealing pipelines after they received knocks, repairing ruptures and defects that are a result of damage or which have been incurred during the construction phase itself, in concreting, anchoring floating docks, sealing leaky ships or detonating underwater rocks. In such cases the repair materials are mixed above water – but in the case of application sites that lie much deeper – it is also mixed below water in a diving bell that is open towards the bottom. Because of the transport from the surface to site and the cramped conditions inside the diving bell only small quantities can be processed at any one time.
The decision as to which technological solution will be used in a particular repair rests solely with the applicator. For small-scale and prompt repairs on steel or concrete reaction resins are preferred. However, these have until now been unsuitable to the medium in which they are applied. They are frequently problematic since the unsatisfactory consistency and drying time of the material add further difficulty when mixing and applying under the cramped conditions inside the diving bell.
With MC-DUR underwater pro MC-Bauchemie has now developed a two-component special duromer resin that is ideal for use underwater as it is adapted to suit these particular conditions.
The innovative product is made up of main component and hardener component, each in containers of 1.5kg and mixed in equal measure 1:1. A container size matched to suit one dive at a time, plus a comparatively high viscosity of the materials ensure that the reaction resin material does not run, be it above or below water, and that it can easily be kneaded by hand in preparation for application.
Tinting one component white and the other one black ensure they are mixed correctly. A homogenous grey tone indicates correct and complete mixing. Manageable quantities of the resin are created that the diver can then easily insert into the area to be repaired, either by hand or using as tool. The pot life is roughly 30 minutes. The material can be applied in temperatures ranging from 8 to 30°C. When fully cured it has a compressive strength of 84 N/mm² and a bending tensile strength of 35 N/mm².
An additional advantage of MC-DUR underwater pro is that it has extremely good bonding both on steel and on concrete. The high-tech system enables not just universal application suitability, but also a rather simple, fast and reliable application that brings significant cost-savings for applicators. After all, a diving hour costs between 100 and 300 Euros, and with a maximal allowable diving time of three hours per day a diver must carry out as many repairs as possible.
For the use in permanent water contact MC-DUR UW pro has already been REACh approved. This means the product does not pose a risk to the environment and can safely be used in all areas, including water reservoirs used for drinking water supply. The new material is currently being tested in practice in various climate zones, so that customers are able to rely on the quality assurance of MC. It is used in Spain, for example, in the port of Algeciras, on rainwater drainage pipes that enter the sea near Calpe and in the repair of the floating docks in the port of Cartagena before these are being shipped to their final destination in Algeria.
In the near future further tests are planned in Gdansk, Poland, Countless customer enquiries have already come in from Brazil, Germany, Ireland, Portugal and Romania – thanks to the exceptional performance spectrum of MC-DUR underwater pro. At the same time MC is expanding its international contact list of specialist diving firms.
Harbours are the most important import and export hubs. The majority of international trading activities run through them, as there is no other means of transportation which is as cost-effective as the ship. Investments in sea routes and waterways are, therefore, important for all national economies. MC-Bauchemie is involved in maritime construction and repair projects throughout the entire world
Because of the expected increase in international traffic volumes and the resulting necessity to further incorporate sea routes and waterways into freight transportation, the maritime economy has a very promising future despite the effects of the current financial and economic crisis. In comparison to roads and rail, waterways are considered a very environmentally and climate-friendly alternative. Unit 2008, the maritime economy was able to record a persistent boom phase. The growth, figures in sea transportation, sea harbours, shipbuilding and offshore technology have increased progressively each year. Despite the down-turn since 2009 caused by the effects of the fast-reaching global financial and economic crisis, the maritime economy is and remains a future industry with high potentials of growth and employment.
As concrete is the most important material for maritime installations, this opens up an important field of activity for MC. On construction sites throughout the world, from Brazil to the Maldives, the admixtures together with injection and surface protection products are ensuring safe new buildings and repairs.
Recently, in the major Brazilian harbour of Santos, a damaged ferry terminal was repaired. Above all, the concrete protection system Zentrifix KMH was used as an anti-corrosion primer together with MC-DUR 1103 as a sealer. Due to the tide and the short time allowed for the repair, the work was difficult. However, with careful planning and preparation, it could be successfully completed. Injection solutions with MC-Injekt provided for water-tight walls and floors in the construction of South America’s largest dry dock in Rio Grande. The 350 x 130m dry dock is intended to repair and maintain offshore platforms.
In Spain, MC is involved in a number of renovation and expansion projects in harbours ranging from Barcelona to Santa Cruz de Tenerife.MC admixtures are used in the concrete for the caissons. After construction, tugboats are used to tow these reinforced concrete caisons to their respective locations, where terminals or piers are being constructed. Sometimes the caissons are placed at depths of over 30m. The technology for the planning and construction of these caisons is firmly anchored in Spain. Sliding form technology is used predominantly during production. This method offers high performance characteristics but requires an uninterrupted work flow and a specific properties of the concrete used. It must exhibit a good fluidity and pump ability over long distances. In addition, a low water/cement ratio is required in order to ensure the durability of the concrete in the aggressive seawater environment. MC-PowerFlow, the new generation of PCE admixtures, is capable of ensuring optimal operating efficiency.
In the Belgian harbour of Antwep, 25 year-old silo installations were re-contoured with the Zentrifix and Nafufill product systems and protected with EmceColor-Flex. Bridges, purification plants and waste incinerators together with tank farms and roll-on/roll-off installations were built and repaired in the Amsterdam harbour with admixtures, retarding agents, and ombran products.
The largest harbour in the Netherlands and Europe, Rotterdam, is characterised predominantly by the local petrochemical installations. The MC-DUR coating systems have been used for buildings by Shell, Exxon Mobil and Akzo. In the Botlek Tunnel, sealing operations using MC-Injekt have been carried out. The Maasvlakte power station, built by Eon, rests on a base slab that was cast with concrete incorporating MC admixtures. In the container terminal, the slabs are made of pre-fabricated sections, which were also produced using MC concrete admixtures and release agents to accelerate the concreting procedure.
In the North Sea, MC products are used continually for repairs and concrete protection of offshore platforms. MC concrete admixtures are also used for the offshore wind farms developing along the German coast. In Hamburg's harbour, quay walls are impregnated with Emcephop, bridges are coated with MC-DUR and silos in the potash harbour are primed inside with Colusal VS and externally with the Setonflair surface protection system. In the Elbe Tunnel, the crack-bridging Zentrifix F 92 surface protection system was used with MC-Injekt resins and concrete admixtures. Even when constructing the HafenCity, concrete admixtures and site products were delivered along with injection materials for the metro connection.
In addition, in Bremerhaven's roll-on/roll-off harbour, bulkheads to secure the banks were created with MC products and, in Wilhelmshaven, they were used to create support surfaces for a tanker loading bridge. When constructing the new Jade-WeserPort, concrete admixtures and injection resins are used. Injections were also used on the Huntel lock. In Papenburg on the Weser, the construction dock of the Meyer shipyard was expanded using concrete, which was treated with MC admixtures. In addition, admixtures were used in the harbour embankments in Rostock and in the production of floating pontoons there.
In the Irish harbour city of Dublin, the harbour port tunnel was injected with MC materials and in Limerick, a road tunnel was created using caissons with MC materials. The Polish harbours of Gdansk and Kolobrzeg had their wave-breakers produced with MC products. Concrete admixtures and surface protection products from MC have also been used for inland harbours, such as Europe's largest inland port in Duisburg, in Dusseldorf and in Vienna.
Even in Abu Dhabi, in the United Arab Emirates, underwater repair works were recently successfully carried out with MC products in the Yas Grand Prix Circuit Marina yacht harbour. The Zentrifix surface protection system and the Emcekrete grout were also used for repair works on a pier installation in the Maldives.
Due to the extensive global experience in the field of concrete protection and admixtures for maritime infrastructures, MC is now the most sought-after manufacturer in this field anywhere in the world.
Even in Abu Dhabi, in the United Arab Emirates, underwater repair works were recently successfully carried out with MC products in the Yas Grand Prix Circuit Marina yacht harbour. The Zentrifix surface protection system and the Emcekrete grout were also used for repair works on a pier installation in the Maldives. Due to the extensive global experience in the field of concrete protection and admixtures for maritime infrastructures, MC is now the most sought-after manufacturer in this field anywhere in the world.
The significance of Poland as a business location has continually grown in recent years. Poland has been a member of the EU since May 2004 and has become one of the most powerful growth engines in Europe. As a result, Poland also increasingly attracts investors from abroad. MC-Bauchemie, which was one of the first construction chemical companies in Poland, has now grown to be an important supplier to the Polish construction industry and is benefitting from the construction boom, which is closely linked with economic growth.
With an average annual growth of 3.9 º/o, the Polish economy has grown more than four times as strongly as Germany (0.9º/o) in the last ten years. The peak value in 2007 was a 6.8º/o growth in gross domestic product (GOP). It is particularly remarkable that Poland was the only member of the EU not to slip into recession in the crisis year of 2009, with a GOP growth of 1.7%. In the first quarter of 2011, growth is estimated at 4.5º/o - and for 2012, the forecasts are very promising for the construction and assembly sector with 12º/o. The growth in sales of the MC business field of Construction Chemicals in Poland actually exceeded this ambitious value in the first two quarters of 2011 with a 40º/o increase in turnover.
MC-Bauchemie has recognised the great potential of the country very early. In 1993 the production site in Sroda Wielkopolska near Poznan was founded, which is now managed by Alina Stelmach. Initially, products from the Ultrament line such as tile adhesives and joint fillers were in particular demand on the Polish market.
The Construction Chemicals (CC) sector was successfully developed by Sales Manager Tadeusz Wasag. To rapidly compensate for the backlog in this field, the European concrete standards were introduced into Poland.
With the growing concrete industry and increasing demand for concrete technology and innovative products, the company quickly established itself as one of the leading construction chemical specialists in Poland. A nationwide distribution network was set up and the production of powder and admixtures was started shortly after.
The field of Protection Technologies (PT), managed by Sales Manager Daroslaw Demski, has also developed successfully. MC Poland's product range has been continually expanded. Today, it includes products and systems from the entire MC range. In 2001, the production department responsible for the production of construction boards was also put into operation at the Sroda Wielkopolska factory, which exclusively manufactured these products for all the other companies of MC-Bauchemie. Today, the company in Poland employs about 200 people, of which roughly 50 people work in production.
Currently, in addition to the encouraging economic data, the Polish concrete industry is receiving an additional boost from EURO 2012 football competition in Poland and Ukraine. For example, three modern stadiums are constructed in Warsaw, Gdansk and Wroclaw. As part of this major sporting event, the country is also investing in the infrastructure. The investment total for 2010 to 2015 alone is 40 billion Euro. A good 75 º/o of this is being invested in road construction. About 4,000 km of motorways and roads are plant with funds from the EU's "Operational Programme: Infrastructure and Environment" scheme. In addition, the construction of modern sewer systems, and treatment plants as well as the new building and expansion of airports and sea ports is planned for the longer term. Billions in investment will also reinforce the energy sector. New power plants will be built, existing ones upgraded and renewable energy sources developed. EU funds will also be available for the energy sector. With the building of countless new shopping centres and hotels as well as the renovation of industrial and old buildings, interesting market potential for investors from Poland and abroad should be realised.
MC-Bauchemie Poland will provide the construction industry with products for all sectors, which will be individually adapted to meet local requirements. For the expansion of traffic infrastructure and the sewage systems and the construction of new water treatment plants, the company will be offering integral protective coating systems from the PT sector such as Nanoperm for treatment plants or MC-RIM products for traffic infrastructure, as well as repair materials such as Nafufill. MC products will also be used to build the new football stadiums. In Gdansk, 30 tonnes of Emcekrete 860A is being used for filling in the support of the steel construction for the roof. In Wrodaw MC-DUR is being supplied for the flooring of the stands and MC-Quicktop is being used for the finish of the concrete construction.
The range of projects dealt with in Poland is long, varied and includes many Polish prestige buildings. MC's involvement covers brand new football stadiums for EURO 2012 to repair of power station cooling towers and refurbished motorway bridges through to new architecturally extraordinary museums. "In addition", says the CC sales manager, "we are currently involved in the major cultural investment of Warsaw, the Museum of the History of the Polish Jews. The demanding construction project, that is being erected on the site of the former Warsaw Ghetto and is expecting 500,000 visitors per year from 2013, was designed by Finnish architect Rainer Mahlamaki. "We are providing MC-Top Primer and MC-PowerTop products for this outstanding building:' The Olympic Centre in Warszawa was also built with the help of admixtures and concrete cosmetics from MC.
MC is also very visible in infrastructure development. “An important project is the construction of the Kwiatkowski dual carriageway in Gdynia'; emphasises Daroslaw Demski. The objective of this project, carried out with support from the European regional development fund, is the economic development of the Pomorze region. "A link between Gdynia harbour and the road network should'; according to the PT sales manager, "strengthen the economic site and create the climate for smooth national and international trade. Nafufill GTS is being used here': Furthermore, MC is involved in the bridge construction of motorways 1, 2 and 4 as well as the repair of a 200km stretch of motorway with Nafufill KM 103, 110 and BS and MC-DUR products Muraplast FK 61 and Centrilit Fume FX will also be used for the Sucharski Bridge in Gdansk. An especially prestigious project with MC participation is the elevated road bridge over the river Warta in Konin. The pre-stressed bridge is considered the largest of its kind in the country with 6.45km length and 14m width. Freeze- thaw resistant concrete, incorporating Muraplast and Centrament admixtures, was used for the superstructure.
As well as infrastructure, another important area for MC Poland is energy. The demand for efficient and environmentally-friendly power stations in the country is still high. As a result there will be countless renovation and redevelopment projects of older power stations. The Belchatow lignite-fired power plant near Lodz, exists since 1981. Today it is considered Europe's largest hydrocarbon fuel led power station and the largest lignite-fired power plant in the world, with 4,440 MW of capacity and an efficiency of 42%.
MC, with its special knowledge in the field of cooling tower maintenance, has been involved in the ongoing works for years. To protect the concrete, the 48,300m2 large interior and 12,400m2 1arge external concrete shells and the flue-gas table of the new 180 m high cooling tower have been coated with the copolymer protective coating MC-DUR 702. The interior concrete she ll was primed and sealed with MC-DUR products. MC is involved in various major sewage projects. In the last few years, the treatment plant in Warszawa has been completely refurbished. This was necessary as only 50% of the municipal sewage could be treated in the two plants. The plant, which has now been completed in the southern town of Czajka, has a capacity of 435,000 m3 per day for 2.1 million PE. In total, 150,000 m3 concrete were poured with MC-DUR products. During the modernisation of the treatment plant in KrakowPiaszow, products from the MCRIM range were applied.
As it will become more and more important, due to the rapid growth of the construction sector in Poland, to offer products and services in a more customer oriented manner, MC began with the restructuring of the service and sales network. As CC project manager, Justyna lwanska is jointly responsible for supporting this development.
The establishment of more regional service centres, which until now only existed in Germany, is an important factor. They practically operate like small construction chemical companies and have been geographically positioned to cover every region in the country. As well as the office in Wrodaw, with the headquarters of Protection Technologies, centres have already been established in Sroda Wielkopolska for the western and north-western regions. The office in Warszawa is responsible for central Poland and the north-east. The headquarters of the sales manager of Construction Chemicals is also here. A further service centre for north Poland is in Gdansk.
In addition, further service centres are planned in Rzeszow for the south-east of the country. "This structural re-development of MC-Poland is being carried out in conjunction with a noticeable increase in staff numbers'; Justyna lwanska points out "New technical advisers, who will strengthen the sales network and will allow the individual regions to be served more efficiently, are being hired:' Just like the service centres, they are strategically placed to be able to support projects in the field in every region.
Alongside the structural changes, MC customers can also continue to rely on the knowledge of Michal Preiss and his colleagues in the concrete laboratory in Sroda Wielkopolska For example, the laboratory, which has recently employed more staff, provides support to select the ideal concrete admixtures, checks pressure resistance and examines the grading curve of additives. The technical department also constantly monitors the cement manufactured in Poland to optimize MC admixtures. In addition, it prepares mix designs for special concrete - e.g. for bridge construction, which must have a higher strength. In this respect, the MC team is proud of the fact that it now works together with all cement factories in Poland.
"All we do for the new structure of the company in Poland serve the purpose of optimising customer service and to fully harness the market potential. Because market research shows that construction chemicals' potential in Poland could develop in dimensions comparative to Germany in the midterm' Justyna lwanska says.
The high level of customer focus of the company is also reflected in its activities to permanently improve the qualification of its staff. To keep Polish partner companies always up-to-date with the latest standards of concrete technology, regular "Concrete Days" are established in Sroda Wielkopolska. Since 1999, operators and experts from science and technology meet MC specialists every two years for a two-day exchange of experiences about problems and innovative developments in concrete technology. At this year's event on 11th and 12th October 2011, Prof. Giergiczny from the technical school in Gliwice will be the guest of honour. More than 100 further participants are expected.
In the first half of the year, workshops took place in Bieszczady and Jaszkowo (West Poland) as part of the MC-Forum series, in which 24 and 27 people respectively took part. In addition, 80 people participated in practical presentations of the ECE 2015 products in connection with the Transmix system in Sroda Wielkopolska, Jaworzno, Zgierz and Warszawa. 80 also attended in five events on the subject of using Oxal products for the preservation of historic monuments. MC also supports graduates from the AGH University of Science and Technology in Krakow with their final year thesis.
The dynamic development of the construction industry in Poland repeatedly sets MC-Bauchemie experts new challenges. The most important indicator of growth is the country's cement consumption. This was 17.2 million tonnes in 2010. For 2011 the amount has been estimated at 18.5 million tonnes, an increase of 7.5%. The forecast for 2020 is 22.8 million tonnes. However, with efficient production and service centres in the most important parts of the country, MC Poland is well-positioned to fulfil the future requirements of the Polish construction industry.
Airports are regarded as national advertisements and characterize the international image of a country not least by heir architecture and technical sophistication. That is why- as well as for safety reasons- great attention is paid to quality of all aspects of new construction, repair work or capacity extensions.
Airports have a special significance for MC-Bauchemie: on the one hand they connect the MC locations worldwide, on the other they are sites where different product systems are used. MC has been involved in numerous challenging airport projects such as Berlin-Schonefeld, Dresden, Dusseldorf, Frankfurt, Leipzig-Halle and Munich. MC products were used internationally at airports in Athens (Greece), Dublin (Ireland), Constanta (Romania), Gdansk (Poland), Kiev-Boryspil (Ukraine), Copenhagen (Denmark), Prague Ruzyne (Czech Republic), Rome (Italy), Sao Paulo (Brazil), Szczecin and Warszawa (Poland) as well as in Vienna (Austria). Usage areas further include the assembly hangar of the Airbus A 380, hangars on military airfields and airport parking areas.
The different sectors of an airport are characterized by the fact that they are exposed to extreme operational demands- e.g. the take-off and landing areas of runways- and they have to be modified over time to satisfy increasing standards. As always safety has first priority and high standards for the materials and systems must be met. They have to prove their quality and suitability in validation procedures that are often very complex.
The taxiways and runways have to withstand extreme mechanical loads from aircraft taking off and landing. In addition, there are the seasonal operational demands caused by frost and de-icing agents. That is why special concrete mix designs as used in road construction are used. In order to guarantee the safety of the aircraft while on the ground, the concrete surface must have an adequate and consistent surface profile to provide grip.
By using Muraplast plasticizers and Centrament Air air-entraining agents the concrete for the runways and taxiways will have the desired consistency range as well as air-pore content to achieve outstanding concrete properties required by the given exposition scenario.
The expansion of Stuttgart airport is an ideal demonstration of this. The runway had to be rebuilt and moved 1,400 m eastward, to comply with international standards. Admixtures and the repair mortar Reparoxyd from MC were also used during the construction of the runways at the largest international commercial airport in the Ukrainian capital Kiev. The concrete surfaces there have to withstand regularly and repeatedly the numerous take offs and landings of the Antonow AN-225, the world's largest aircraft with a take-off weight of up to 600 tons.
MC made essential contribution in developing the mix designs for the runway concrete for several large projects in conjunction with the construction companies involved. For example the cycle time for the production of large concrete areas was reduced considerably. The concrete runways as well as in the aircraft de-icing sections can be kept skid-resistant by using MC-Grip to increase surface grip. The product system involves the spray application of an epoxy resin which is then, while still wet, scattered with a special aggregate to give a skid resistant surface. Currently the extensive skills and expertise of MC is in demand for the construction of the North West runway and the associated taxiways at the Frankfurt/Main Airport extension.
Repair work or expansion projects regarding airport infrastructure are another sector where MC's innovative concrete admixtures, concrete repair systems and industrial flooring make an important contribution, by fulfilling the customers' technical and aesthetic demands.
For example light fluid separators (grease traps) were sealed with ombran FT at Berlin-Schonefeld airport. Furthermore, access ramps to the terminal building of Leipzig-Halle airport were injected with MC -DUR 1264 KF and columns were coated with Zentrifix F92. In Dusseldorf hangars have been provided with new floor coatings. At the Romanian airport Constan1a for example the quick hardening synthetic mortar MC-DUR 3500 was used to repair damage on the airfield.
Airport construction and repairs demand the best from engineers and contractors in terms of logistic and time management. Experience and a close dialogue between those involved are therefore even more important. With their expert advice and innovative technology MC also makes a positive contribution to the smooth running of critical projects on large and small airports.
Multi-storey and underground car parks are an essential part of the traffic infrastructure in densely populated regions and at the same time project an image of the operator. They relieve the streets of stationary vehicles and offer users shortest possible distances, for example to the shops, to work or for changing to other means of transport. These purpose-built buildings are however also exposed to considerable stresses by the continuous traffic, and require special solutions when being maintained or repaired. MC-Bauchemie has taken care of the upgrading and embellishment of multi-storey car parks with a wide range of tailored systems.
Multi-storey car parks and underground garages often have a grubby image attached to them in the minds of many car drivers. They consider them to be dark, dirty, confined and dangerous and avoid using them wherever possible. This was confirmed last year by the multi-storey car park test carried out by the German Automobile Association (ADAC e. V.): Out of 50 multi-storey car parks tested in ten big German cities 28 were given the grade "adequate'; five "poor" and three "very poor': 13 achieved "good" and "very good" was only given once. Accordingly, the test winner defines the positive characteristics that a car park must have in order to make the user feel comfortable just by parking there: it should be well laid-out, light, clean and suitable for the disabled. Important also are clear signposts, large and visible ramps as well as sufficiently wide and easy to enter parking spaces that are not limited by pillars.
Big shopping centres in city locations in particular have recognised the significance of the car park as a marketing instrument, as it contributes to presenting the company's "visiting card': What use is the most beautiful marble portal, if the visitor has to go through a multi-storey car park that he or she thinks of negatively? After all, the first impression on entering the car park transmits an image of the company that is behind it. That is why dark areas, floors covered with puddles, damp walls or dripping ceilings are counterproductive in generating successful customer loyalty.
Structural damage is above all the result of the high operational demands that the parking garages are faced with. They are considered to be traffic structures and not structures. Especially in heavy use structures, the permanent mechanical load leads to increased wear. This becomes visible particularly at certain "stress points'; where the vehicles brake, stop, accelerate or drive along curves. That is the case above all in the barrier area of the entrances and exits, on the ramps, in curves and on the access to the individual park decks and results in the abrasion of the surfaces. In addition, there are the seasonal temperature variations that can often affect the basic structure of the building directly due, in many cases, to its open construction.
In the winter chlorides and de-icing salts are brought in by the vehicles. They penetrate into the concrete and trigger dangerous pitting corrosion on the reinforcement, whereby not only damage is caused, but in extreme cases even the stability of the building can be affected. Moreover, there is the danger of water penetrating into the car park in areas in contact with the ground.
MC-Bauchemie has developed complete system programmes for the protection and repair of multi-storey car parks, with which the most diverse types of problems can be solved. These range from waterproofing to the creation of coloured traffic and guiding navigation concepts.
Penetrating water is the enemy of every concrete construction -this is also valid and applies especially to multi-storey car parks. Water-bearing cracks can form in the short or long run. MC has, in its portfolio, highly elastic, low temperature flexible and fi reproof injection resins for the sealing of cracks. These were used for example in the new construction of a two storey underground garage with 580 parking spaces of a shopping centre at the Berliner Platz in Bottrop. "Typical crack patterns, extensive moisture penetration of the base plate and rising moisture on the walls indicated the presence of water under pressure during the shell construction phase'; Dipl.-lng. Holger Graeve of the Protection Technologies Division says. "We were able to find a remedy with MC-Injekt 2300 top: 'It consists of a very low viscosity elastomer resin for the sealing of cracks, joints or voids in components.
It was injected by means of packers in the Bottrop underground car park. In the case of large-area moisture penetration grid inject ions were carried out. After successfully stopping the water penetration, further work on the interior was able to continue, so that a light, friendly and above all dry underground car park is now available to users.
The underground car park in the new construction of the Titanic Signature Building in Belfast, Northern Ireland, presented a similar type of damage. It is the centrepiece of a new city district that was erected right next to the docks where the Titanic" was once built. The architecture of the building reflects maritime elements and recalls the bow of a ship in its design. Inside there is an interactive experience museum, where visitors learn all about the legendary "Titanic" and the tradition of ship building in Belfast. For the foundations over 1,000 bored piles, up to 23 m deep, were poured. The base slab with a volume of 4,200 m3 is regarded as the largest concrete pour carried out in Eire to date.
During this construction project water also penetrated via the base slab. In addition the bored piles leaked, so that water was able to get into the building through 0.1 - 0.2 mm wide cracks in the wall s. From October 2011 to February 2012 injection work primarily using MC-lnjekt 2300 plus was carried out on the wall and floors.
A further project in Belfast is the Victoria Square Shopping Centre. There are over 80 shops and restaurants, spread over four floors, on 75,000 m2. An atrium forms the centrepiece, spanned by a 35 m diameter glass dome. The associated underground car park provides parking for approx. 1,000 vehicles on two levels. During the construction phase over 2.5 km of cracks and construction joints were successfully sealed with MC products in only four weeks.
Water can also penetrate the building through expansion joints between individual components. This was the case in an underground car park in Landau (Palatinate). Typical damage for underground car parks was visible, where the highly stressed joint construction in the transition from access area to parking deck was leaking. MC-Injekt GL-95 TX was ideally suited for this application. Extensive gaps and joints were able to be sea led with the highly elastic hydro-structural resin. It is highly flexible when cured and has high swelling properties in contact with water. MC-Injekt GL-95 TX was therefore also able to follow more extensive joint movements and ensure long-term tightness in the case of the repairs in Landau.
A distinction must be made between manufacturing faults and environmental influences in determining the cause of damage to concrete. Exhaust gases, acid rain, frost and de-icing salts can attack the concrete. Its chemical properties are then modified in such a way that the steel reinforcement in the concrete begins to corrode. Rust takes up two to three times more volume than non-corroded steel. Pressure stresses are the result and the concrete cover is pushed off (spalling) - the need for repair is clearly visible.
This initial situation was visible in the case of a multi-storey car park at the University of Wuppertal. It was finished in 1976 and provides a floor space of approx. 14.300 m2 on 17 half levels. "Only the floors of the open-air decks were protected by a layer of mastic asphalt, all other levels and the walls had no surface protection in their initial status'; says Rafael Sass, concrete repair specialist at MC. "Accordingly, extensive corrosion damage to the reinforcement of the walls due to the entry of de-icing salts and carbonation was found during the site inspection The polymer-modified PCC concrete substitute Nafufill KM 250 was used in this case. The re profiling mortar is a fibre reinforced concrete substitute for the repair of concrete components in dynamically as well as structural areas. It has a high resistance to carbonation and frost de-icing salt and also fulfils al l the requirements of fire safety. During the repair of the car park walls the larger surfaces were treated with the one-component polymer modified dry sprayed mortar Nafufill GTS. In addition, the walls had to be protected not only permanently against chloride entry but also against all types of contamination - from algae infestation to graffiti. This was resolved with the surface protection system Emcephob NanoPerm P. It consists of a special aqueous two-component polymer combination and provides safe concrete protection and dirt protection. As the surface is absolutely tight, scratch-proof and solvent-resistant, graffiti and other contaminations can be removed with the specially matched Emcephob Basic Cleaner without leaving any stains. Even a new construction can require concrete repair measures after only a short time. In the multi-storey car park of the Connect Business Park in the Romanian capital Bucharest cracks in the slab of the open air deck were visible after the first frost period. The damage was remedied by a specialist company under the terms of the guarantee. There pair concept first of all included sealing the cracks by injection techniques. After carrying out the substrate preparation, the in-situ concrete was repaired over an area of 1,000 m2 in the structure with Nafufill HB (primer coat) and Nafufill KM 130. This PCC concrete substitute is suitable for the repair of horizontal areas in structural and non-structural areas with or without dynamic stress. Nafufill KM 130 is resistant to frost de-icing salt and chloride-proof. Finally, the surface was sealed with MC-DUR 1277 WV. In order to seal the connecting and expansion joints the applicator used the sealant Mycoflex 450. Once the work was finished, the parking deck was able to be used again without restriction.
If the repair of a multi-storey car park is to be successful on a lasting basis, the concrete surfaces must be effectively protected against pollution. This is particularly true for traffic and parking areas. Modern floor coating systems are available here. "But especially this sector is strongly regulated'; says Dr.-lng. Peer Heine, Head of Flooring Systems at MC. "Yet these regulations are insufficient, because the technical aspects are incomplete and imprecise. As a result, faults can still arise in the floor coating despite design and execution in compliance with the regulations:' That is why MC offers a great variety of systems for the floor coating of multi-storey car parks that all do far more than just fulfil the standard requirements. By means of intensive advisory consultation and extensive service the floor coating specialists of MC select the product best suited for each project. Different demands are often placed on different parts of the building, which require systems tailored exactly to these requirements. In addition, aesthetic values play a role, because traffic control is often conveyed by a coloured floor coating. A particularly impressive example of both technically and aesthetically successful repair is the multi-storey car park Schutzenstrale in Bamberg. The damage was so advanced that the reinforcement had to be completely exposed in the base slabs and the beams. Their repair was carried out with in-situ concrete. For the partial re profiling of smaller damage Nafufill KM 250 and fine mortar Nafufill KM 110 were used to level out the concrete surfaces among other things. On the basement floor leaky joints were sealed by injecting with MC-Injekt GL-95 TX. During the final floor coating MC-DUR 1252 was used on approximately 13,000 m2. The special epoxy resin coating is suitable for car park surfaces both internally and externally and has high abrasion resistance as well as resistance to chemicals and UV light. First of all a wearing courser is applied, on which quartz sand was scattered while still fresh. After drying a top sealing coat follows, also using MC-DUR 1252. This system was also applied in a multi-storey car park in the old town of Trier on 13,000 m2. In the Bamberg multi-storey car park colour coding was also used to help to guide the users. The corners and bends at the entrances and ramps are coated blue, to make the traffic routing and right of way regulation clear. Yellow lines mark the parking spaces and pedestrian paths. MC has the coloured epoxy resin sealing MC-DURVS-PUR in its range for this, which is very robust as well as chemical and UV resistant. It is applied easily with roller, brush or airless sprayer onto the finished coat.
If the repair of a multi-storey car park has to be done during its operation, quick and robust cement-bonded floor coating systems are required, so that the respective construction area can be released for use again quickly. Emcefloor PCC was developed for this. This one-component. Self levelling special polymer cement coat (PCC) is a genuine alternative to "classical" floor coatings. It convinces above all by the fast, economic processing, as it is applied in one working step including roughness adjustment. During the rapid early strength of 15 N/mm2 after one day, it is possible to apply an overcoat after two days already. In addition, the system is osmosis-proof.so that it can be used in areas, where there is the possibility of rising damp of the concrete. Emcefloor PCC was applied for example during the repair of Cologne's Bruckenstral3e multi-storey car park in a thickness of almost 10 mm. Top sealing was carried out with MC-DUR 1252. In the new construction sector it was used in the multi-storey car park of the "Technopolis" electrical store in Sofia, Bulgaria among others. The walls and columns here were left in a vibrant shade of red, so that the corporate design of the company was also implemented in the car park. In a multi-storey car park of the supermarket chain "Guanabara" in the Brazilian town of Nova in the federal state of Rio de Janeiro the client chose MC products as well for the floor coating. The multi-storey car parks of numerous international airports such as Dusseldorf. Zurich-Kioten or Copenhagen are equipped with MC -coatings. As in these examples, countless car park buildings all over the world were able to be embellished by specific repair and surface protection systems and saved from further damage and loss in value.
Remarkable buildings often require remarkable solutions. This is particularly true for the pump storage power plant Hohenwarte II. MC-Bauchemie had developed a special repair concept for their dam wall. After an extensive trial phase, which lasted about ten years in all, the execution has now started step by step.
The pump storage power plant Hohenwarte II is situated near the village of the same name near Saalfeld in Thuringia. It is part of a unit of two dams and two power plants. The upper dam lake is manmade between two hills with a storage volume of 3.28 million m3 The dam structure consists of a 1,443 m long gravity dam made of concrete and a 680 m long raised embankment dam. The need for renovation of the concrete construction built between 1956 and 1963 was already clearly visible in 2000. On the downstream side of the dam water could be seen seeping through the horizontal joints and also penetrated the lower control corridor of the wall through leaking vertical joints.
In view of the length of the dam the operator Vattenfall Europe Generation decided to have a 330m2 sized test area sealed first. Ulrich Lange, Product Manager Special Coatings at MC-Bauchemie, developed a repair concept for this that was exactly geared to this special application and put it into practice as a trial. "First of all the joints were sealed by injection with the hydro structural resin MC-Injekt GL 95 TX. Then the extensive covering of a concrete section and the adjoining joints followed with a sea ling coat on a drainable underlay made on site", explains Lange. As base material for the surface sealer, the robust, equally drainable geo composite MC-FLEX Base was applied and secured with corrosion-resistant nails at nine points per square metre. Flexible rendered elastomer resin was used as sealing coat in the system. For this, the manually applied variant MC-FLEX 2098 was used for the adhesive bonding of the overlap joints of the geo composite. The actual sealing coat was then applied by machine with MC-FLEX 2097 in a two-compound injection process and the edge sealed with stainless steel flat material attached to roof bolts for plastic mortar and a EP-mortar wedge at the side.
In addition, a resin with a dry coat thickness of approx. 250 ~m was applied as ultraviolet protection over the entire surface. This sealing system is equipped with a drainage system. It offers the advantage, that water, which might possibly escape from the building structure and get behind the sealing coat, is evacuated immediately. A drainage gully is fixed at the lowest point of the sealing area. The work was carried out in 2001. After a service time of ten years the surface has now been assessed. No changes in the material could be found here, compared with its condition when new. As the system has proven its worth in the long-term practice test, further joints are now going to be sealed with this process. In the summer of 2011 three additional test joints were sealed for this purpose, in order to determine current time and cost estimates. Further joint seals are planned for 2013.
Concrete, the most commonly used construction material, increasingly plays a creative role as well as a functional role. The trend toward fair-faced concrete becomes more apparent with architects especially, as special impressions can be created with fair-faced concrete. This places high demands on the surface quality of the concrete- whether it is applied on the construction site or delivered as a pre-assembled element. The application is however often full of problems. Broken edges, honey-combs, pores, cavities, colour variations or contaminations can occur. More than four decades ago, MC-Bauchemie issued quality standards on this and coined the phrase" concrete cosmetics'.
As market leader in Germany MC today supplies primer coats, coarse and fine fillers as well as hydraulically setting filler compounds in a large variety of products and colours. The continually evolving concrete cosmetic fillers Emcefix and Nafuquick have proven their worth over time. Problematic concrete surfaces can be treated cosmetically with MC products. The wide range of colours, the miscibility of shades among themselves and the possibility of adding colour pigments makes it possible to design any desired colour. In addition, the special polymer admixtures Repacryl were developed, which influence the application properties positively and modify the colour shades and tones. By adding the accelerator Fluresit 4 DS the filler compounds set quicker, without influencing the colours.
Moreover, MC offers to applicators an all-round service from advisory consultation to equipment recommendations. Specialists are trained as concrete finishers and application equipment can be supplied along with the materials upon request.
Last year MC's concrete finish filler range was extended by the brands MC-Powertop and MC-Quick top. These brands constitute the filler systems developed and produced in production facilities outside Germany. They have been certified for the European market. In addition, special tools are made available with the MC-Concrete Finish Set that consists of all the equipment such as e.g. the finishing sponge MC-Top Sponge, the rubber float MC-Top Rubber, the sanding mesh MC-Top Float and all the other necessary concrete finishing tools. In the near future there will be a sample case, the MC-Concrete Finish Sample Box, in order to advise customers better with all product samples and colour tones. The existing production locations for concrete cosmetic products in Germany, Poland and Russia will be supplemented by a production centre in Spain in the medium term. This should ensure that MC reaches the customer with their advisory services and products even quicker and more effectively.
When the Luneburg-Scharnebeck ship lift facility was formally opened in 1974, it was the largest twin vertical ship lift in the world. It enables modern freight ships en route between the Elbe and the Mittelland Canal to rise 38 metres. But concrete is afflicted by the ravages of time, the aggregate cement combination used at the time led to what is known as alkali silica reaction or ASR.
This is the term given to a chemical reaction that results in an expanding alkali silica gel produced within the concrete. This absorbs water and the swelling of the concrete structure can cause internal damage. From the long-term perspective, the stability of the concrete structure can be jeopardised. Urgent action was therefore necessary. The task for MC's Protection Technologies division was to identify the best material for the purpose. It was a tremendous challenge in which they had to see off two competitors. By October 2010, when the first trial areas had been applied by the Bauschutz company, an experienced team from MC (technical advisers headed up by Robert Schnell) was at the site with its various super structures. The upshot of the technological examinations conducted on the concrete in the spring of 2011 was- Nafufill GTS-HS was the only suitable material for this job. The different criteria in favour of its use included the alkali-silica resistance, the superior bonding to the substrate and the good visual appearance of the trial areas.
Now the logistics department had to be on the ball. MC-Bauchemie held numerous meetings with the Waterways and Shipping Office (WSA) of Uelzen and the main contractor to ensure that there would be enough silos in place so that these could be filled on demand. There was one further requirement. Ana lyses had to be carried out to guarantee that the materials delivered consistently maintained the same quality and characteristics as the trial material. This was especially important to prevent any adverse reactions occurring between the existing concrete and the new repair material.
The real challenge presented by this project was and is to achieve the ideal level of cooperation between all parties involved. "Nothing was left to chance, so we arranged with the contractor, Bauschutz, to work on a new trial area to test the compatibility of the pumping installation with our material", said Werner Baumgart, Protection Technologies. The project engineers paid particular attention to the vertical rise of 5O metres. The final surface structure was also tested, with two centimetres applied in the initial step followed by one centimetre in the second, which was t hen rubbed down to produce a smooth finish. Around 900 tonnes of Nafufill GTS-HS were applied using a Mader pump.
The curing required the application of painter felt, which was suspended with the felt side facing the structure. It was permanently kept moist using a sophisticated hose system. For the partial re-profiling Nafufill KM 250 HS was applied. The compact MC-Fastpack Power-Tool was used to inject MC-Injekt 2300 plus for treating minor cracks. Around nine months passed from the initial trial areas to the first deliveries. Then in July 2011 the first silos were filled. Because the Osttrog lift facility was closed to shipping, the renovation works had to be performed using high-pressure.
The works not only concerned the 13,000 m2 concrete facade, there was also corrosion protection work to be performed on the basin area and other steel elements. The works will be fully completed before the end of the year. Then from 2013 to 2014 the second work phase will commence with the renovation of the Westtrog lift facility.