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Thursday, 17 November 2016

Constructing mega structures with modern chemicals

Globally, high-tech infrastructure and mega constructions have become a ubiquitous need to step up towards the creation of the ‘new world’. This has made way for high performance, better quality construction materials which are being churned with the latest chemical technology for building next-gen infrastructure.
By Debarati Das
State-of-the-art roads, bridges, power, ports, highways, awe-inspiring buildings, office spaces, opulent residential complexes; all invoke the grandeur of the new world that we are moving towards. The construction industry is witnessing its most exponential phase and this growth will only see its graphs striding upwards in the near future.
To meet this surge, the desire for faster and sustainable construction is becoming the key. Construction chemicals are playing a more important role than earlier to meet the demands of higher strength, durability, economy and sustainability of concrete structures. The need for better construction chemicals is further witnessing a significant growth because of the rising awareness about construction quality and technological advancements.
The construction chemicals market is broadly classified into concrete admixtures, technical mortars, adhesives and sealants, waterproofing solutions, flooring compounds, repair and rehabilitation.
According to Markets and Markets report, the global construction chemicals market is estimated to grow at a rate of 7.62 percent between 2015 and 2020 to become a $33.98 billion industry by 2020. Growing number of new housing, commercial spaces, and public infrastructure projects in the Asia-Pacific region, especially China and India, and other developing countries like Brazil, Egypt, Colombia, UAE and Saudi Arabia is further strengthening the construction chemical industry. Other major markets include the US, Germany, Japan and Italy.
Various global companies are expanding their base in the Asian countries to be a part of this boom in construction activities. “Asia Pacific is one of the fastest growing markets globally, and South Asia is a strategic growth engine of this market,” said Himanshu Kapadia, vice president, market management, construction chemicals Asia Pacific, BASF. To strengthen its South East Asian hold, BASF unveiled its fifth and largest construction chemicals plant in India this year at Nellore.
The group also expanded its base in Sri Lanka with a new facility in Colombo to manufacture chemicals for the company’s concrete admixtures and products. “Sri Lanka’s construction industry is witnessing an upward swing and is today one of the significant contributors to the country’s GDP. This growth is creating a demand for high-performance concrete admixtures,” said Aruna Deepthi kumara, chief executive officer, BASF Lanka Pvt Ltd.
Among the various infrastructural advancements happening across the globe, residential building is expected to hold the major market share for construction chemical followed by commercial buildings. This growth in construction activities has been further instigated by changing lifestyles, growing urbanisation trend, rising disposable income and demand for enhanced aesthetics of residential and commercial infrastructures.
Advancements in construction chemical technology in concrete admixtures, flame retardants and adhesives & sealants etc, are providing the much-needed design flexibility to modify the physical and chemical properties of a structure. New age construction chemicals are enhancing the compressive strength, durability, surface finish and resistance to adverse climatic conditions making the structures sturdier than earlier.
Tracking the trends
Construction chemicals are nothing but chemical compounds that are added in the formulation of various specialty chemicals in construction materials such as cement, mortar and concrete. These formulations improve the workability, performance, compatibility of the structure, increase their life and provide protection from environmental hazards. The chemicals also minimise the quantity of cement and water generally required during the construction activity.
Some of the construction chemicals which are seeing major growth include materials such as cementations; admixtures like waterproofing admixtures, plasticizers, accelerating agents, retarding agents and others; adhesives & sealants like acrylic adhesives, polyurethanes, polyvinyl acetates, epoxy and others; and flame retardants like ATH, antimony oxides, brominated, and chlorinated.
With the need for better chemical compositions to suit the future construction demands, globally construction chemical industries have significantly increased their investments for research and development of new products and applications. New age construction chemicals industry is witnessing demands of:
• Energy-saving materials and technologies: Urethane foam thermal insulators, infrared ray–reflecting coatings and solar cell roofing–related materials are making their way to dominance.
• High durability chemicals and technologies like SBS as asphalt modifiers, advanced protective coatings and repair products
•Maintenance-assisting chemicals like photocatalytic coatings
• Environmentally friendly products like waterborne coatings and formaldehyde free adhesives etc.
The construction chemicals industry is witnessing major growth and innovation in areas of admixtures, flame retardants, adhesive and sealants. Some of the advancements that are happening in these sectors are as follows:
Chemical Admixtures: play a central role in modern concrete materials and technologies. Admixtures significantly reduce the cost of concrete construction, help modify the properties of hardened concrete and ensure the quality of concrete during mixing, transporting, placing, and curing. There are five types of chemical admixtures: air-entraining, water-reducing, retarding, accelerating, and plasticisers (superplasticizers). Other varieties of admixtures have functions such as corrosion inhibition, shrinkage reduction, alkali-silica reactivity reduction, workability enhancement, bonding, damp proofing, and colouring.
Air-entraining admixtures are used to purposely place microscopic air bubbles into the concrete.
• Water-reducing admixtures reduce the requirement of water content for a concrete mixture by about 5 to 10 percent giving higher strength to concrete without increasing the amount of cement. New admixture technology has developed mid-range water reducers that reduce water content by at least 8 percent and tend to be more stable over a wider range of temperatures. Using an advanced formulation technology, Fosroc recently developed a product with a reduced water powder ratio yet offering better flow and higher strength. Conbextra Sureflow 100 can be used with adjustable water consistency and can be mixed in less than 3 minutes. It also provides good workability retention, even at high temperatures, meaning that pouring large volumes becomes easier. “We have developed entirely new formulation chemistry which we have called Sureflow. Experienced applicators will notice a real difference in the performance of this grout,” said Alex Yin, Fosroc’s head of cement technology.
• Retarding admixtures slow the setting rate of concrete and are used to counteract the accelerating effect of hot weather on concrete setting. This helps to keep concrete workable during placement and delay the initial set of concrete.
• Accelerating admixtures increase the rate of early strength development; reduce the time required for proper curing and protection; speed up the start of finishing operations and modify the properties of concrete in cold weather.
• Superplasticizers, also known as plasticizers or high-range water reducers (HRWR), reduce water content by 12 to 30 percent and can be added to concrete with a low-to-normal slump and water-cement ratio to make high-slump flowing concrete.
• Corrosion-inhibiting admixtures slow down the corrosion of reinforcing steel in concrete. It can be used as a defensive strategy for concrete structures, such as marine facilities, highway bridges, and parking garages, which are exposed to high concentrations of chloride.
Flame Retardants: Bricks and mortar are no longer the only material used for construction. Several advanced materials technologies such as plastic insulation, composite materials, metals and glass, are being used to make way for creative design solutions. However, all these materials have raised environmental, energy and safety concerns. Flame retardants play a vital role in building materials and products to meet fire safety standards and codes. Flame retardants stop or slow the spread of fire enhancing the escape time for occupants. Flame retardants raise the threshold temperature at which a material ignites, reduce the rate at which materials burn, and minimise the spread of fire. Flame retardants can be applied in electrical wires and cables, insulation materials, paints and coatings, building materials, structural and decorative wood products, roofing components, composite panels, decorative fixtures etc. Some of the flame retardants applications are as follows:
Cables and Electrical Wiring: Modern structures contain a large number of electrical and electronic equipment (EEE) for which wires and cables run vertically from floor to floor behind the walls of a structure, potentially increasing the fire risks from short circuits and other electrical malfunctions. To reduce the chances of electrical fires, builders use plastic insulation treated with flame retardants to coat wires and cables providing a protective covering for conductors and cables.
Structural Insulation: Some of the modern insulating materials used include polystyrene foam boards and rigid polyurethane foam panels. The former is being used to insulate most areas of a building, including in interior walls and over concrete walls to insulate basements, and ceilings and roofs.
Structural Elements: Various structural elements in homes, offices and public buildings consist of materials that, without protection, would be a fire hazard if they came in contact with an ignition source. For this, steel structures, metal sheets, wood, plaster and concrete used in building construction are coated with special paints and sealants that expand and form a thick insulating, nonflammable foam.
Adhesives & Sealants: The adhesives and sealants market is one of the strongest growing markets in the construction chemical industry. According to reports, adhesive bonding technologies will soon replace mechanical fasteners and other alternative joining systems. While emulsion and dispersion adhesives and sealants will remain the leading product type, reactive adhesives and sealants will drive the market in future. Silicone and polyurethane adhesives and sealants are expected to see potential demand in among reactive types.
The Indian dynamics
The Indian construction chemicals sector is increasingly being referred to as the sunrise industry. The UN also pointed that India is on the “brink of an urban revolution” and expects the population in towns and cities to reach 600 million by 2031. This has led to a surge in critical infrastructural projects like roads, bridges, power, ports and highways have paved way for the growth of constructions industry in India. Furthermore, government initiatives such as Housing for All and100 Smart Cities has further accelerated the need for construction chemicals. The government plans to spend over Rs 48,000 crore on building smart cities with smart technologies over the next five years. New affordable housing units will require modern construction technology with speciality construction chemicals opening up huge growth opportunities for the sector.
The Indian construction chemicals sector stood at around Rs 3,500 crore in 2014 and is expected to grow at 15 percent over the next five years, reaching Rs 7,000 crore by 2019-2020. However, the Indian construction chemicals industry is highly fragmented with a mix of national, regional and global construction players. The industry has an oligopoly of the top 5 players who account for 50 percent of the market. The rest comprises of small and unorganized players.
Apart from new construction projects, repair, renovation and rehabilitation form a huge portion of the industry as a large portion of existing Indian infrastructures comprise of ageing and deteriorating buildings due to poor quality construction materials and low maintenance. According to international standards, while average life of buildings is more than 100 years globally, the average life of structures in India is just 20-25 years. This increases the need for high-end construction chemicals products to match global standards. Construction activities will constantly rise to keep in sync with the rising population, expanding economies and need for high-tech structures to suit the needs of future applications. Constructions need to be sturdier, safer yet flexible to address the changing demands of the environment. Fortis, construction chemicals will continue to have an increasingly important role to address.
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