天津某基坑工程事故原因分析及处理措施

Accident Analysis and Treatment Measures of a Foundation Excavation Engineering in Tianjin

结合天津市某基坑工程事故实例,分析该基坑事故原因,并提出有效的处理措施。分析表明,该基坑内外未采取防水、排水措施,基坑暴露时间过长,监测缺失,降雨量过大是基坑事故发生的主要原因,施工单位未按图施工,擅自将H型钢长度缩短至12m是基坑事故发生的直接原因。根据事故发生特点,采取坑内堆砌砂土袋、支护结构增设加筋水泥土桩锚等措施控制基坑支护结构变形,防止基坑坍塌。结果表明,该处理措施有效控制了基坑变形的进一步发展,取得了良好的处理效果。

Combined with a practical excavation engineering accident in Tianjin, this paper analyzes the cause of the accident and offers effective method. The analysis shows that there are some reasons, such as both inside and outside excavation did not take water control and drainage measures, the excavation exposed for too long time, lack of monitoring, and excessive rainfall. Moreover, the immediate cause of this accident is that construction unit failed blueprints and they shortened the length of the H-beam to 12 meters. According to the characteristics of the accident, the authors take measures that let construction unit piled sand bags along the inside of excavation and add reinforced cement-soil pile anchors which could control structural deformation of excavation support to prevent collapse. The results show that the measures effectively control the further development of deformation, and obtain good effect.