西南某炼油厂强夯法处理填土地基事故分析

Aanalysis on an accident of filled ground reinforced by dynamic compaction of an oil refinery in southwest China

对西南某炼油厂强夯法处理填土地基事故原因进行分析,并给出处理建议。经分析,厂区西北部填土厚度较大,该区域内采用天然地基的建(构)筑物地基基础不均匀沉降问题较严重。地表水入渗及地下水的侧向径流补给使填土地基含水量、地下水位均有明显提高。通过对比补勘与第二次详勘期间填土的各项物理力学指标及降雨前后填土地基的载荷板试验结果可知,厂区填土具有遇水软化的特性。地基深部存在厚薄不均的软弱下卧层,强夯处理难以保证该层软弱土的处理效果,不利于地基变形的稳定。建议加强地下水位、地表沉降及结构变形监测,并根据各建(构)筑物地基基础及上部结构的变形情况,给出合理的处理措施。

This paper analyzes causes of an engineering accident of the filled ground reinforced by dynamic compaction of an oil refinery in southwest China,and also the treatment suggestions are given.It is shown that the thickness of soil in the northwestern of the plant is relatively large,and the uneven settlement of the foundation of buildings and structures with natural foundation in the area is serious.Surface water infiltration and lateral runoff recharge of groundwater have significantly improved the water content and groundwater level.Comparing physical and mechanical indexes of the fill during the supplementary survey and the second detailed survey and the load plate test results of the filling before and after the rainfall,it can be seen that the filling has the property of softening when it contacts with water.There is a weak underlying layer with uneven thickness in the deep part of the foundation.It is difficult to ensure the treatment effect of the soft soil in this layer,which is not conducive to the stability of the foundation deformation.It is recommended to strengthen the monitoring of groundwater level,ground settlement and structural deformation,and reasonable treatment measures are given according to the foundation deformation of buildings and structures.