Behaviour of glass aggregate concrete in fire

In response to the sustainability agenda in the construction industry, the use of glass aggregates in concrete is currently being investigated. The annual global glass waste is estimated to be approximately 14 million tons. The use of glass as aggregate is a significant step in converting waste to a resource. This paper reports effort related to investigating fire behaviour of concrete incorporating glass aggregates with particular reference to residual strength and stiffness properties. This investigation involved 48 concrete test cubes and cylinders. Half of the test samples were made using natural aggregate concrete and the other half made incorporating 10% replacement with glass aggregates. The glass aggregates were of the same grading curve as the natural aggregates. The test pieces were subjected to various heating regimes in the range which is known to be critical for the mechanical properties of concrete. The test pieces were cooled in a controlled environment. The test cubes were used to investigate the residual compressive strength. The test cylinders were used to determine the state of internal fracture as well as the residual stiffness as determined by Ultrasonic Pulse Velocity (UPV), static and dynamic modulus of elasticity. UPV data indicated that there is approximately 10% increase in internal fracture when glass aggregates are used. The residual static modulus, dynamic modulus and compressive strength exhibited similar reduction when glass aggregates were incorporated.