Improving the Interaction Between Heavy Trucks, Roads, and Bridges

A major co-operative international research program known as DIVINE (Dynamic Interaction between Vehicles and Infrastructure Experiment) has been completed by the Organisation for Economic Cooperation and Development OECD). DIVINE involved seventeen OECD member countries, and included specialists in vehicles, pavements, bridges, road management and transport policy. Inter-linked research projects were carried out in nine countries and the project took almost four years to complete. DIVINE set out to investigate the benefits of “road-friendly” suspensions for reducing pavement wear and to develop better means of assessing vehicle suspensions for road-friendliness. This paper summarises the most important results of DIVINE and presents means of assessing and simulating the road-friendliness of truck suspensions. Dynamic loading depends on the vehicle suspension, and the use of air suspension generally reduces dynamic loading. Current air suspensions could be improved in certain respects and the effectiveness of their dampers influences dynamic loading. Current designs of air suspension also have advantages for vehicle stability and safety performance, ride quality, driver comfort and quieter operation. The results of the DIVINE Project have shown that, under controlled experimental conditions, the dynamic loading associated with conventional mechanical suspension causes a significant increase in pavement roughness (or unevenness) in certain aspects of cracking and rutting. Assessment of vehicles for road-friendliness was extensively researched in the DIVINE Project and it was found that dynamic suspension tests utilising a road simulator provide the most effective means of vehicle assessment. Simpler “drop” tests also provide good results, and the methods contained in EC Directives have been supported by the DIVINE results, with some suggestions for improved accuracy.