天然地基上的筏板基础受力及变形分析

对天然地基上采用筏板基础的两栋建筑的实测资料进行分析，总结了不同刚度的筏板基础的受力和变形特点。分析发现，筏板基础的刚度对基底土反力分布产生很大的影响，而地基土的弹性模量变化对土反力分布影响不大，但对筏板的相对弯曲及沉降影响较大；在上部结构的施工过程中，筏板的中性轴在不断上移，筏板内的钢筋应力值始终很小，因此建议设计时应减少筏板的配筋率。

Analysis of the Behavior of the Rafts' Deformation and Interior Force on Natural Subsoil

The characteristic of deformation and interior force of the fafts with different rigidity is analyzed based on the monitored data of the rafts placed on natural subsoil.The results show that the stiffness of the rafts has greater influence on the soil reaction than the elastic modulus of the soil,but the elastic modulus affects the relative bending of the raft to a certain degree.It is also found that,with the construction of the superstructure,the neutral axis of the raft moves upward gradually.The steel stress remains much smaller than the design stress,so it is recommended that the reinforcement ratio of the raft be reduced.