Concrete

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Constrofacilitator

Knowledge and b2b portal for construction and infrastructure

eMAGAZINE July 2023

V05 eM-07

CONCRETE

Inside Silica fume concrete- advantages, types

F and applications

Unlocking the Potential of Ultra-High

F Performance Concrete

Early age cracking in concrete- causes,

F types and how to prevent it

What is aggregate Its advantages, types

F and applications

Polymer Concrete as Innovative Material for

FDevelopment of Sustainable Architecture Self-compacting concrete advantages,

F materials and applications

Advantages, Types and Applications of

F Natural Pozzolans in Concrete

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CONCRETE

Concrete has been witnessing a growing demand and increasing importance in India due to several factors. The country's rapid urbanization and infrastructure development projects have led to a significant surge in concrete usage. Its versatility, cost-effectiveness, and durability make it a preferred construction material for roads, bridges, buildings, and other infrastructure. Additionally, advancements in concrete technology have made it possible to produce highstrength and eco-friendly concrete, addressing sustainability concerns. In this edition of eMag, we have covered topics like Polymer Concrete as Innovative Material for Development of Sustainable Architecture, Self-compacting concrete advantages, materials and applications, Early age cracking in concrete- causes, types and how to prevent it, Advantages, Types and Applications of Natural Pozzolans in Concrete, Unlocking the Potential of Ultra-High Performance Concrete, What is aggregate Its advantages, types and applications, Silica fume concrete- advantages, types and applications. July 2023 • Constrofacilitator

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Polymer Concrete as Innovative Material for

04 Development of Sustainable Architecture Self-compacting concrete advantages,

08 materials and applications

Early age cracking in concrete- causes,

14 types and how to prevent it 19

Advantages, Types and Applications of Natural Pozzolans in Concrete Unlocking the Potential of Ultra-High

23 Performance Concrete

What is aggregate Its advantages, t

28 ypes and applications

Silica fume concrete- advantages, types

31 and applications

08 14 19 23

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Constrofacilitator • July 2023

POLYMER CONCRETE

Polymer Concrete as Innovative Material for Development of Sustainable Architecture

Er. Shamanth Kumar M, Managing Director, Skanda Group of Constructions ABSTRACT In the recent scenario, Polymer concrete has been developed as an innovative architectural material due to its high performance as compare to conventional materials. Polymer concrete has many advantages over conventional Portland Cement Concrete, such as high mechanical properties, rapid hardening, durability, and resistant to chemical and biological effects. Sufficiently large amount of research work has been carried out during the last few years and reported that Polymer concrete has ability of application in the advancement of construction industries. In this article, we have reviewed the status of Polymer concrete and its application as sustainable building material. INTRODUCTION Polymer concrete (or PC) is a composite material that consists of aggregate, filler, and polymeric binder, by replacing the hydraulic cement of conventional concrete with polymeric resins. Polymer concrete has many advantages compared to the cement Portland concrete such as: rapid hardening, high mechanical strengths, improved resistance to chemicals etc. The concretepolymer composites can be classified into Polymer concrete, Polymer cement concrete, and Polymer impregnated concrete, among which the Polymer concrete is well known for its versatile structural applications. Construction materials modified by polymers were already used in 2000～3000 B.C.. Since 1950's, there has

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been increasing interest in concrete-polymer composites as new construction materials in the construction industry but for enormously improving the properties of concrete by polymer based concrete was studied and explored after 1966. In the past few decades, many countries engaged actively in development of polymeric materials in mortar and concrete. Polymer concrete (mortar) is currently being used in Japan as popular construction material because of its high performance, multi-functionality and sustainability as compared to conventional cement mortar and concrete. Building industry has been the largest user of plastics since around 1955 and the Association of Plastics Manufacturers in Europe (APME) reported that the building and construction sector is still the third largest user of plastics. Building construction accounts for up to 13% of total global epoxy consumption in applications including flooring, decorative aggregate, paving, and construction. Due to the rapid setting characteristics, high strength-to weight ratio and ability to withstand a corrosive and aquatic environment, Polymer concretes are progressively being used as alternative to cement concrete in many applications, such as construction and repair of structures, highway pavements, bridge decks, and waste water pipes. In addition, these new materials also save natural resources protecting the environment. Polymer concretes are, therefore, classified as construction materials that support the sustainability

July 2023 • Constrofacilitator

POLYMER CONCRETE

aspects of construction. POLYMER CONCRETE MATERIALS Polymer materials (also called as resins) play important role in binding the organic substrate (i.e., concrete/ aggregates) to each other due to their inherent adhesive nature. Liquid resins for the polymer concrete include unsaturated Polyester (UP), Epoxy (EP), Vinyl ester (VE), Polyurethane (PUR), and Poly-methyl methacrylate (PMMA). The most versatile polymers used in structural applications are unsaturated Polyesters and Epoxies due to their excellent mechanical properties and cost efficiency. Ø

Polyester Resin

Unsaturated polyester resin made by reacting glycol with maleic anhydrous could be cured to an insoluble solid simply by adding a catalyst. This discovery was made by Carleton Ellis in 1930. In liquid form, the resin is stable for several months and years when kept at room temperature and can be cured into a hard solid within few minutes, whenever required. Curing takes place by addition of a peroxide catalyst which leads to chain reaction that involves conversion of double bonds into single bonds without release of any by-product. Styrene is used to links together the reactive double bonds of different polyester chains to form a strong threedimensional polymer network. By changing the reacting components of polyester (i.e., diacids and diols), a great variety of polyester resins can be prepared for a wide range of applications including furniture, building panJuly 2023 • Constrofacilitator

els, cultured marbles, etc. Some of the polyester types of architectural importance are: Ø Ø Ø Ø

Resilient Polyester for a tough product. Chemical resistant Polyester for tanks and pipes applications. lFire-resistant Polyester for building panels. lWeather resistant Polyester for outdoor structural panels.

Polyester resins are preferred in Polymer concrete composites due to its low shrinkage, better bonding ability, and resistance to chemical attack properties. Ø Epoxy Resins Epoxy resins are characterized by the possession of more than one 1,2-epoxy group per molecule. The important epoxy resins are reaction products of bisphenol-A and epichlorohydrin. The resin systems consist of liquid epoxy, diluent s, fillers, and poly-amine or poly-amide curing agents. Cycloaliphatic amines are used when either better low temperature cure or adhesion to wet concrete is desired. Most cured epoxy resins provide amorphous thermoses with excellent mechanical strength and toughness, outstanding chemical, moisture, corrosion resistance, and good dimensional stability. Epoxy flooring's provide wear resistant and chemical-resistant surfaces to food processing and chemical plants where acids normally attack concrete. Due to its superior performance characteristics and outstanding formulating versatility, epoxy resin is widely accepted for bonding and structural applications. Epoxy systems

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POLYMER CONCRETE

for roads, tunnels and bridges are effective barriers to moisture, chemicals, oils, and grease. They are used in new construction as well as in repair applications. Epoxy resins are widely used in bridge expansion joints and to repair concrete cracks in adhesive and grouting (injectable mortar) systems. Epoxy pavings are used tocover concrete bridge decks and parking structures. The resins used in the production of Polymer concrete must have low viscosity and higher boiling point (i.e., above 70oC) for easy and effective penetration between aggregates. Considering the environmental safety issues, Epoxy and unsaturated polyester with low styrene contents (i.e.,