长河坝水电站右岸导流隧洞进口高边坡稳定性有限元计算分析

FEM CALCULATION OF HIGH INLET SLOPE OF DIVERSION TUNNEL ON RIGHT BANK OF CHANGHEBA HYDROPOWER STATION

由于受地形条件限制,长河坝水电站导流洞进水口边坡几乎整个边坡设计为直立坡,最大高度为148m。这种边坡布置方式在国内、外很少见,其变形、稳定问题关系到该工程导流方案的成败,非常重要。为了解边坡的稳定性,以及了解边坡加固方式的有效性及合理性,采用有限元方法对边坡开挖、加固过程进行模拟,给出边坡的变形、屈服区以及锚杆等应力情况,特别分析裂缝和裂隙对于边坡变形、屈服以及锚杆应力的影响,利用降强度计算方法得到边坡的抗滑稳定安全系数。研究成果对边坡的开挖及加固具有指导意义。

Because of the limit of landform of damsite,the inlet slope of the diversion tunnel of the Changheba hydropower station has to be designed vertically with the biggest height of 148m.This situation is seldom to meet at home and abroad,and its deformation,stability issues related to the success of the project diversion program is very important to the construction of the hydropower station.To know the stability of the slope as well as the effectiveness and reasonability of reinforcement,the FEM is used to model the excavation and reinforcement process of the slope,and the deformation,yield zone and the bolt stress distribution are obtained.Especially,the analysis of the impact of cracks and fissures for the slope deformation,yield stress,as well as anchor.The strength deduction method is also used to calculate the safety factor of the stability.Finally,some conclusions are discussed which are helpful to guide the excavation and reinforcement of the slope.