NUMERICAL ANALYSIS OF CONCEALED KARST CAVERNS INFLUENCE TO TUNNES STABILITY

摘要

Karst disaster is often occurs in the tunnel construction in mountain district. When most middle and small sized caverns are concerned, the Karst tunnel problems caused by this sized caverns are mainly studied numerically with the consideration of the influence of different positions and scopes of the concealed Karst caverns on stress field, displacement field and the internal force of support structure for tunnel with the popular shape type. The influence of surrounding rock conditions and the initial stresses to the displacement, stress and internal force of the tunnels are tested numerically. On the basis of numerical experimental analysis, the present paper analyzes the internal mechanism of tunnel displacement variation rule resulting from different scopes and positions caverns and makes the partition graph of cavern influencing range.