地基土支承损失对框架梁弯矩的影响

该文利用有限元法对一幢12层钢筋混凝土框架结构进行了土──上部结构的空间协同工作分析，旨在研究地基土中发生支承损失（即土中孔洞）时对框架梁弯矩的影响。数值结果表明，当支承损失发生于基础底面时，会对梁弯矩产生较明显的影响，随着孔洞尺寸的加大，弯矩变化意为剧烈。但随着孔洞与基础底面距离的增大及楼层的提高，其影响迅速减小。

The beam bending moments of a 12-storey RC frame with and without soil support loss is invesigated. The analysis was made using the three dimension finite element method in which the soil foundation and frame were idealized as elastic perfectly materials. The void eas been set up as different size and location. Results of the study indicate that the substantial effects on the bending moments of beam can be made as the void was adjacent to the bottom of the foundation. With the void dimension enlarge, the influences become more obvious. With the stories increase, the influences lessen gradually. The further away from the foundation that exists the local support loss, the influences may be negligible.