筏板刚度对桩筏基础下卧层附加应力影响分析

ANALYSIS OF INFLUENCE OF THE RAFT RIGIDITY ON THE SUBSTRATUM′S ADDITIONAL STRESS OF THE PILED RAFT FOUNDATION

采用有限单元法对不同筏板刚度下桩筏基础下卧层附加应力的分布规律进行分析。计算结果表明,筏板刚度对桩顶反力、桩端阻力和下卧层附加应力分布的不均匀性有很大影响,且在刚性基础中表现尤其明显。结合有限元法和Geddes公式的计算结果表明,筏板刚度还引起附加应力沿深度分布的变化及附加应力影响深度的变化。

By finite element method,the distributions of additional stress of piled raft foundations in different raft rigidities are analyzed.The results show pile top reaction,pile tip resistance and additional stress of the substratum are greatly influenced by raft rigidities,especially in the rigid foundations.Combined the results by finite element analyzing and Geddes′ stress formula calculating,the raft rigidities also impact the relationships between vertical additional stress and depth and stress' respondence depth.