Safety Assessment of Long and Steep Downhill Roads Based on Grey Cluster

The safety grade of Long and Steep Downhill Roads (LSDRs) on mountainous expressway is determined on the basis of analysis of safety factors, and the safety evaluation index system and the weights are build. Based on the theory of grey clustering, the classic whitening weight function is improved, and a gray fixed weight-clustering evaluation model of LSDRS is established to evaluate the security level. The process and the method were verified by application. Results show that using the proposed method and process to classify and evaluate the security rank of LSDRS on mountainous expressway can provide theoretical basis to improve safety, and make the improvement more systematicness and purposiveness.