摘要
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解表明 ,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线基本对称外 ,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 ,甚至有可能突然增大。沟谷深度和坡度越大、构造应力量级越高 ,切应力越大 ;在沟谷横断面上 ,塑性区的厚度具有明显的垂向变化 ,坡顶大 ,中间小 ,沟谷正下方又增大。
Investigating valley stress field is of importance to the researches 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 section of valley, which parallels basically the trend of valley. In the direction 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 about 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 gradually big, reaching maximum at the valley botton. Tangent stress is relative with the depth and gradient of valley and tectonic stress. The thickness change of plastic zone in vertical direction is noticeable.
出处
《水文地质工程地质》
CAS
CSCD
2000年第4期12-16,共5页
Hydrogeology & Engineering Geology
基金
国家杰出青年科学基金资助项目!(495 2 5 2 0 4)
