Concrete based on Polyurethane System
Concrete is one of the popular construction material used all over the world. But, over the last few decades, polymer concrete is being introduced in order to fulfil various constructional requirements (such as zero water absorption, quick setting time, earthquake resistance, impact barriers, high flexural strength, chemical resistance, etc.) The objective of this project is to improve the properties of concrete by incorporating polymer system so as to make it suitable for applications like industrial flooring, thin section precast walls, etc. The project aims at evaluating compressive strength and water absorption of polymer based concrete system over conventional concrete with and without fibrous reinforcements. The system consisted of Polyurethane (water based emulsified resin), hardener, white cement, fine silica and fibrous reinforcement (polyester fibres).Overall, six formulations with varying fibre content were used for the studies. The standard samples based on conventional concrete as well as polyurethane based concrete system were casted and subsequently tested for compressive strength and water absorption after 28 days’ post casting. In both the cases, it has been observed that the compressive strength did not increase drastically with varying content of polyester. The polyurethane based concrete system has very low set (curing) time as compared to conventional concrete. The compressive strength achieved by polyurethane base concrete within 3 days was around 80% of its total strength (28 days) while conventional concrete achieved strength around 60% of its total strength within 7days of time. In case of conventional concrete there is necessity of water for its curing while polyurethane based concrete water present as dispersion medium itself serves the required purpose. It was also observed that polymer system based concrete has compressive strength comparable with M35 mix design of conventional concrete. Hence, using polyurethane based concrete material for ordinary and standard conventional concrete applications can be beneficial.
Keywords - Polyurethane Based Concrete, Fibres, Conventional Concrete