临水软土基坑双排钢板桩支护结构变形分析

Deformation of double steel sheet-pile support structure in soft soil foundation pit adjacent to water

针对软土地层中双排钢板桩支护结构变形过大的问题,以某船厂基坑为依托,通过现场测试数据分析、理论计算及数值模拟等手段研究双排钢板桩在软土地层中的变形特性,分析变形过大的原因。采用极限状态识别和临界状态参数反演的方式,提出根据现场数据进行回填反压应急处理的方法以及采用大排距双排灌注桩进行加固的措施。结果表明,提出的应急处理方法和加固措施取得了良好的效果。双排钢板桩围堰在软土基坑中变形往往较大,进入临界状态后将迅速产生较大的变形,应采取有效的坑内加固措施,避免超挖。

Regarding the problem of excessive deformation of double steel sheet-pile in soft soil stratum,we take a foundation pit of a shipyard as an example,study the deformation characteristics of double steel sheet-pile in soft soil stratum by means of field test data analysis,theoretical calculation and numerical simulation,and analyze the causes of excessive deformation.By means of the identification of limit state and the inversion of critical state parameters,we put forward the emergency treatment method of backfill back pressure according to the field data and reinforcement measures of double-row cast-in-place piles with large row spacing.The results show that the proposed emergency treatment method and reinforcement measures achieve good results.Double steel sheet-pile cofferdam is often deformed greatly in soft soil foundation pit,and it will be deformed rapidly when it enters critical state.Effective reinforcement measures should be taken to avoid overbreak.