深厚覆盖层中竖井井壁负摩阻力分析

结合某深厚覆盖层土层超深竖井工程,利用有限元分析软件,对竖井井壁在含水层疏水沉降作用下的负摩阻力进行模拟研究.通过研究得出了以下结论:底部含水层疏水沉降引起的竖井井壁负摩阻力沿整个井土接触面分布,并呈现出"两头小,中间大"的分布规律;负摩阻力峰值一般不在含水层内产生,而是在竖直方向上离疏水面最近的土层内产生;负摩阻力值的大小受降水深度的影响要比受水平距离的影响大;负摩阻力的大小随着降水时间的增加而增加.

Analysis for Negative Skin Friction of Shaft Lining in Deep Overburden Layer

Finite element analysis on negative skin friction for shaft lining under drainage settlement was carried out for a case of vertical shaft project in deep overburden layer. The results show that the negative skin friction distributes in the whole soil-shaft-contact surface, a few at each extreme and many in between. The value of negative skin friction depends on dewatering depth more than horizontal distance apart from soil-shaft-contact surface and it increases with the dewatering time. The peak one appears in the soil layer closest to drainage surface in vertical direction.