Vibration risk for drivers of earth-moving machinery:assessment of the seat dynamic efficiency

摘要

Professional driving is associated with an increased risk of low-back pain,which represents a major health problem for off-road drivers of heavy vehicles typically used in mining,reclamation and construction work. The results of an extensive survey recently carried out on a considerable number of earth-moving machinery (such as excavators,loaders,backhoe loaders,trucks and dumpers) showed that the whole body vibration (WBV) transmitted through the vehicle seat pan usually exceeds the limit value established by law (1,15 m/s2),with the only exceptions represented by trucks and dumpers when transportation along regular stabilized roads is predominant. The article discusses the measure of risk containment starting from the analysis of the seat dynamic efficiency. For a selected number of cases the acceleration values have been simultaneously recorded on the seat pan and on the vehicle frame,at the base of the seat. For each case under investigation the seat transmissibility was determined in order to analyse the efficiency of the seat suspensions and evaluate the prospect of a seat replacement as a possible technical measure for the reduction of the driver's exposure.