Research on Technique of Pre-judge for Waterlogging of Highway Along River in Mountainous Areas

Abstract

This paper gives statement about methods that how to recognize if the highway along river is destroyed by water damage, which on the basis of analyzing influence factors of water damage and pre-judge model of highway along river, then analyzes the result combine with application of JiBei mountain area, verifies its scientificity and effectiveness. Subgrade of highway along river in mountains areas suffers from long-term or discontinuous effect of soaking caused by running water. Under soaking effect of discontinuous water flow, running water porous flows into subgrade through slope of subgrade, then unit weight of backfill materials(), cohesive force(C) and internal friction angle() change suddenly, those factors bring down the mechanic strength indexes of subgrade soil, in this case, subgrade softens like â€rubber road†or occurs the lateral movement, then surface of highway cracks, subgrade starts sinking, spring of subgrade frosts boiling. There are two effects exist in washout result. One is water flows past surface of subgrade slope; the other is washing effect to toe of slope, which is caused by swirling flow and vortex resulting from river bend. Establishing scientific, effective pre-judging and identification system becomes more and more significant and important to build scientific pre-judging model which aims at different geographic areas and guides the deployment of prevention work.