关于《建筑基坑支护技术规程》支挡结构弹性支点法的讨论  

DISCUSSION ON THE ISSUES RELATED TO CALCULATING MODEL OF FLEXIBILITY FULCRUM IN “TECHNICAL SPECIFICATION FOR RETAINING AND PROTECTING OF BUILDING FOUNDATION EXCAVATION”

作　　者：张有祥[1] 周宏磊[1] 李云耀[1] 

机构地区：[1]北京市勘察设计研究院有限公司,北京100038

出　　处：《工业建筑》2017年第8期111-116,138,共7页Industrial Construction

基　　金：北京市科技新星计划项目(Z141110001814086(xx2014B086))

摘　　要：基坑支护设计原理由不能计算变形的二分法、静力平衡法、塑性铰法、等值梁法发展到能计算变形的弹性地基梁法,在弹性地基梁法的基础上又进一步发展到弹性支点法。然而现有的弹性支点法在预应力作用下的受力模型、各工况之间的变形关系及锚杆刚度等方面存在不足,为弥补这些不足,提出了有针对性的加强措施增强上部锚杆以提高基坑的安全性,适当降低围护结构弯矩和下部锚杆强度,提高其经济性。There were some early design methods for foundation excavation supporting which were dichotomy,static balance method,Terzaghi method and equivalent beam method. These methods couldn＇t calculate the deformations during foundation excavation. Then,elastic foundation beam method was used to calculate the deformation during foundation excavation. Finally,the flexibility fulcrum method was developed based on the elastic foundation beam method. However,the existing flexibility fulcrum method had some shortcomings in which were prestressed model,the relationship of deformation between different working conditions and the stiffness of anchors. If those shortcomings were remedied,the upper anchors could be strengthened,and the safety of foundation excavation could be improved.In addition,by properly reducing the bending moment of retaining structure and strength of lower anchors,the cost of foundation excavation engineering could be reduced.

关 键 词：锚杆刚度 变形 预应力 弹性地基梁 弹性支点法 全量法 增量法 

分 类 号：TU753[建筑科学—建筑技术科学]