Engineering properties of tyre chips and Sri Lankan lateritic soil mixtures as a lightweight fill material

Abstract

A number of proposed highways in Sri Lanka are to be constructed over sites underlain by soft peaty clays, due to scarcity of lands. In order to ensure that the in service settlements of these roads are _4 small enough and the roads could functions satisfactorily, number of special ground improvement techniques are to be adopted. Another, alternate approach that could be considered is the use of a lightweight fill material in the construction. Extremely lightweight fill materials such as expanded and extruded polystyrene blocks were used in a number of developed countries in the construction of road embankments over soft ground and in landslide repair. However, these material are to be imported to the country and would be very expensive. As such, from a local point of view a process involving the use of such materials would not be economically competitive. In order to find an economically feasible solution, the lightweight fill materials should be developed with the locally available inexpensive raw material.