螺旋锚群锚极限荷载破坏试验及数值模拟分析

Ultimate Behavior Destructive Test and Numerical Simulation Analysis of Screw Anchor Group

基于螺旋锚群锚极限抗拔荷载破坏试验和三维有限元数值模拟结果,研究了螺旋锚群锚在极限荷载作用下位移变化规律和螺旋锚结构的薄弱区域。螺旋锚群锚端部位移数值模拟结果和实测结果非常接近,在极限荷载作用下,螺旋锚周边土体塑性区域发展较快,土体接近破坏,不能承受更大的荷载。螺旋锚应力峰值位于锚叶与锚杆接触部位,且沿着锚叶半径方向由锚杆中心到锚叶边缘递减,因此将锚叶设计为渐变厚度较为合理,可避免锚叶在极限荷载作用下与锚杆产生裂缝甚至脱离。本研究结果对类似工程具有指导意义。

Based on the results of ultimate behavior destructive test and three dimensional finite element numerical simulation analysis of screw anchor group,the change rule of displacement and weak area of screw anchor under ultimate behavior are studied.The displacement results of numerical simulation and destructive test are very close of screw anchor group.Under ultimate behavior,the plasticity area of screw anchor group surrounding soil is developed rapidly,which close to destroy and the screw anchor group can＇t support more load.The peak stress of screw anchor is located in the contact area of anchor leaves and bolt,which reduce progressively along the anchor leaves radius direction.Therefore,it is more reasonable to design anchor leaves with gradient thickness,which can avoid the damage of anchor leaves and bolt contact area and even anchor leaves break away from bolt.The study results are practical significant to similar projects.