某地铁站深基坑坍塌事故原因分析与建议

Causes and Suggestion on Deep Foundation Excavation Accident in Some Metro Station

以某地铁站深基坑坍塌事故为例,介绍地下连续墙加钢管内支撑方案。并通过勘察事故现场,探讨土方超挖、钢支撑体系缺陷以及基坑监测缺陷对基坑安全的影响。结果表明,施工中,应及时安装支撑、分段浇筑垫层和底板,严禁超挖。由于基坑施工的不确定性,应实施信息化施工。监测点设置应符合规范和设计要求,同时加强钢支撑连接节点构造措施。

Taking the collapse accident of some metro station deep foundation excavation as example,the construction scheme of diaphragm wall with steel pipe support is introduced. The effects on safety of foundation excavation are discussed including soil overbreak,defects of steel support and foundation excavation monitoring by investigation of accident site. The results show that supports are installed in time,cushion and floor are poured in segmentation. Besides,the overbreak is forbidden. Due to the uncertainty of deep foundation excavation construction,informatization construction is implemented, besides,layout of monitoring points accords with current codes and design. Then,structural measures of joints between steel support connections are strengthened.