【作者】 刘波； 宋常军； 李涛； 钱霄； 黄杰；

【Author】 LIU Bo 1 , SONG Chang-jun 1 , LI Tao 1 , QIAN Xiao 2 , HUANG Jie 1 1. School of Mechanics & Civil Engineering, China University of Mining & Technology, Beijing 100083, China 2. Chengdu Xingshu Exploration & Foundation Engineering Co Ltd, Chengdu 610039, China

【机构】 中国矿业大学(北京)力学与建筑工程学院； 成都兴蜀勘察基础工程公司；

【摘要】 为研究砂卵石地层条件下两排锚杆的桩排式支护结构的受力特性,结合成都地区某典型深基坑工程,进行护壁桩钢筋应力现场实测.根据钢筋应力实测值以及基于应力线性分布、应变协调及梁弯曲变形和应力分析理论所求的弯矩,分析了桩身的变形形态.结果表明,桩顶的圈梁对桩具有明显的约束作用,使桩的变形形态完全不同于上端自由的直立杆件;实测钢筋应力最大值仅为钢筋强度设计值的15.5%,远小于钢筋强度设计值,作用于桩身的实际土压力分布模式和大小与经典库伦或朗肯土压力理论不同是其主要原因.本研究为砂卵石地层深基坑桩锚支护结构设计分析提供了参考依据.更多还原

【Abstract】 In order to understand the behavior of supporting structures using two lines of anchors in sandy cobble ground, reinforcement stresses of retaining piles were conducted in a typical project in Chengdu area. According to the measured reinforcement stresses and the computed bending moments of the piles based on the theory of stress linear distribution, strain compatibility and beam deformation and stress analysis, the authors analyze the piles deformation condition. The results show that the ring beams considerably restrict the pile lateral displacement and rotation. The deformation condition of the piles differs from that of upright free-head shafts. The maximum value of actual reinforcement stresses only play 15.5% of yield strength of reinforcements. The main reason is that the actual value and distribution pattern of earth pressure acting on the supporting structures differs from the classical Coulomb’s or Rankine’s earth pressure theory. This research is potentially helpful for the design of anchor pull piles in sandy cobble deep excavation.更多还原