沟谷的隧道效应

深入研究沟谷应力场的一般规律对于岩爆机理和岩爆预测研究是重要的。Ｖ字型沟谷应力场的弹性解析表明，在沟谷横断面上，存在一个大致平行于沟谷轮廊线的切应力高值区；在轮廊线的内法线方向，切应力单调减小，直至过渡到正常应力区，沟谷的隧道效应是显著的。沟谷的下切形成的二次应力场除了关于沟谷中红基本对称外，不具备轴对称特征，从坡顶到坡角，切应力高值区内切应力量级和高值区的宽度逐渐增大，在沟谷正下方达到最大，甚至

Tunnel effect of valley

Investigating valley stress field is of importance to the resea rches on mechanism and prediction of rock burst. Analytic solution of V-shaped valley stress field showed that a high tangent stress zone exists in the cross s ection of valley, which parallels basically the trend of valley. In the directio n of inner normal line of the trend tangent stress gets low with distance before it reaches the normal stress zone. The tunnel effect of valley is conspicuous. Secondary stress field resulting from valley cutting is basically symmetric abou t the valley central line but not of axial symmetry. From top to foot of valley wall, the tangent stress and the width of high tangent stress zone get graduall y big, reaching maximum at the valley botton. Tangent stress is relative with t h e depth and gradient of valley and tectonic stress. The thickness change of plas tic zone in vertical direction is noticeable.