高真空击密法处理吹填粉细砂地基施工参数优化研究

Optimization of construction parameters for dredger fill silty-fine sand foundation treated by high vacuum compaction method

高真空击密法是一种新型的软土地基加固方法,目前对其加固机理的研究还不够深入,施工参数的设置没有合理的依据。依托曹妃甸工业区吹填土地基的工程地质条件运用PLAXIS分析了高真空击密法的施工过程,考虑了不同的夯击次数、夯锤直径和排水管深度的工况,提出了各工况下地基沉降特征。结果表明:夯击次数为4次时,累积夯沉量已经达到了1.58 m;夯锤直径为2.1 m时,区域平均夯沉量最大;排水管深度为6.5 m时,地基模型沉降最大。最后确定了满足工程条件的3个优化设计参数,分别是夯击次数为4次,夯锤直径为2.1 m,排水管深度为6.5 m。研究成果为曹妃甸吹填土地区高真空击密法施工的参数设置和选取提供参考,有效提高了地基处理效率和处理效果。

High vacuum compaction method is a new kind of soft soil foundation reinforcement method.At present,the research on its reinforcement mechanism is not deep enough,and there is no reasonable basis for the setting of construction parameters.Based on the engineering geological conditions of dredger fill foundation in Caofeidian Industrial Zone,we simulated the construction process of high vacuum compaction method by using PLAXIS,considering the different ramming times,rammer diameter and drain pipe depth conditions,we put forward the characteristics of foundation settlement under different conditions.The results show that when the number of slamming is 4 times,the cumulative subsidence has reached 1.58 m;when the diameter of the tamping is 2.1 m,the average sag is the largest;when the depth of the drain is 6.5 m,the settlement of the foundation model is the largest.Finally,three optimized design parameters that meet the engineering conditions are determined,namely,the number of slamming is 4,the diameter of the tamper is 2.1 m,and the depth of the drain is 6.5 m.The research results can guide the parameter setting and selection of high-vacuum density method in Caofeidian area,which can effectively improve the efficiency and treatment effect of foundation treatment.