考虑多栋相邻高层建筑同时施工的桩筏基础-地基相互作用分析

Analysis of interaction between pile-raft foundation and soil considering adjacent high-rise buildings simultaneous construction

结合实际工程,采用FLAC-3D三维数值模拟方法,通过对比单栋高层建筑与其所在的高层建筑群体两种模型的计算结果,分析了多栋相邻高层建筑同时施工对上部结构-地基-基础共同作用产生的影响,包括桩筏基础和地基的变形及受力特性.结果表明:考虑共同作用时,多栋相邻建筑同时施工,会使地基产生附加应力的叠加并向周围扩散;最大沉降区域发生偏移,差异沉降加大;筏板的压应力减小,拉应力增大;桩轴力明显增大,尤其是桩顶轴力.邻近建筑荷载同时施工对共同作用产生的影响在施工中期比在施工完成时表现更为明显.

By comparing the numerical calculation results of two models, single high-rise building and its high-rise buildings system, the effect on super structure-foundation-soil interaction of adjacent high-rise buildings simultaneous construction is analyzed based on a large number of the measured data of field research using FLAC-3D, including the deformation and mechanical char- acteristics of pile-raft foundation and soil. The results show that when considering the interaction, adjacent high-rise buildings constructed simultaneously will cause the additional stress superposition and spreading around; the maximum settlement areas occurs an offset and the differential settlementis increased the raft compressive stress is decreased, while the tensile stress is increased; the pile axial force is increased obviously, especially the pile-top axial force. The effect of adjacent high-rise buildings simultaneous construction in medium-term construction is more obvious.