Cement Grouted Bituminous Mix for Flexible Pavements
Cement Grouted Bituminous Mix (CGBM)
India has the second largest road network with heterogeneous traffic conditions. Although the road construction in India has improved a lot in the last two decades, at times, it is observed that the pavements, especially in urban areas, are unable to last for the desired life and are subjected to premature distresses. One of the major forms of such distresses is moisture induced damages, which occur due to poor drainage conditions in the city roads and sensitivity of bituminous pavements to the water. Keeping this in mind, CSIR-Central Road Research Institute (CRRI) has developed and demonstrated a composite surfacing wearing course for pavements called Cement Grouted Bituminous Mix (CGBM). It is a different type of composite surface course that consists of an open graded high voids bituminous mix as core structure, grouted with a proper cementitious material. Technically, it is a designed amalgamation of concrete pavement and bituminous pavement, thus, consequently and desirably having the nature of both rigidity and flexibility. Need of such new kind of pavement material was being felt for a long time to overcome the deficiencies of the conventional surfacing layer (Bituminous Concrete) while retaining its advantages and benefits. The rutting in bituminous pavements and ‘provision of joints’ in concrete pavements giving poor riding quality are likely to be completely eliminated in future by this new ‘Cement Grouted Bituminous Mix’, which has several important and unique properties; a few of them are listed below: