中南大学学报（自然科学版）2012，Vol.43Issue(3)：1098-1106,9.
软土地层桥梁群桩基础沉降模型
Settlement model of bridge pile group foundation in soft soil stratum
摘要
Abstract
Based on the settlement characteristics of bridge pile foundation on soft soil stratum, the similarity rule of pile group model in this geological situation was derived. The indoor model of pile group foundation with pile cap was self-designed and analyzed. The test results show that the additional stress attenuates with the increase of depth and its distribution form approximates as triangular form within the scope of the pile body. At the same time, the vertical stress of pile-side soil increases as the settlement of pile top increases correspondingly. Moreover, the vertical stress of pile-side soil has not shown obvious converge even though the settlement of pile top is greater near the ultimate load. When the pile group foundation is under applied loads, representing different construction stages, the pile-side soil of upper pile body generates larger excess pore water pressure dissipating with time gradually, which indicates that the soil consolidation process needs some time to be finished. Furthermore, the relationship between load-settlement of pile group shows apparent non-linear characteristics, and its P-S curve can be divided into three /stages of linear phase, yielding stage and the overall destruction phase. In addition, the displacement rebound of pile group is small during unloading because the pile group generates large plastic deformation after the external load is applied. Therefore, the settlement of pile group foundation is one of the control conditions in the pile foundation design.关键词
桩基础/软土地层/模型试验/相似准则/沉降Key words
pile foundation/ soft soil stratum/ model test/ similarity rule/ settlement分类
建筑与水利引用本文复制引用
汪优,王星华,刘建华,蔡君君..软土地层桥梁群桩基础沉降模型[J].中南大学学报（自然科学版）,2012,43(3):1098-1106,9.基金项目
国家自然科学基金资助项目(50808177,50708033) （50808177,50708033）
湖南省自然科学基金资助项目(10JJ4035) （10JJ4035）
中南大学自由探索计划项目(201012200075) （201012200075）
