The mechanism of grouting strengthening for subgrade settlement of mountainous highway, selection of grouting machinery and grouting materials, main construction technology of grouting, as well as the strengthening effect, etc.

This paper analyzes the reasons of subgrade settlement,expounds the measures for preventing the subgrade settlement,and probes into the methods for the treatment of subgrade settlement.

Through quoting the mechanism of the vehicle bump at bridge head in highway engineering,this paper analyzes the reasons of the pavement pression around the inspection well of municipal roadroad and the vehicle bump,and probes into how to prevent the occurance of these problems in the design and construction.