摘要
大量的码头堆场建于深厚软土地基上,地基处理不当容易出现承载力不足、结构位移过大等问题。针对安徽某矿石堆场试运行时出现的基础超大位移问题,分析了试运行地基中超孔隙水压力的累计及消散速度,找出了事件发生的根本原因,提出了排水固结的地基二次处理方案。基于自主知识产权的岩土工程有限元分析软件LinkFEA,采用渗流与变形强耦合的方法,预测了地基按照处理方案的现场试验堆载地基中有无排水措施情况下超孔隙水压力和位移变化过程并与试验结果进行了对比,预测结果与试验比较一致。研究表明,地基中未进行排水板二次处理时,地基中的超孔隙水压力幅值很大,稳定安全性较低,水平位移较大;排水板处理后,地基中的超孔隙水压力得以大幅度削减,稳定安全系数大幅度提高,水平位移大幅度减小。在排水板处理区域地基中的超孔隙水压力在水平方向是波浪变化的,垂直方向上不同土层内的超孔隙水压力差异很大,对固结系数比较敏感。
A large number of dock yards are built on deep soft soil foundations. Improper foundation treatment is prone to problems such as insufficient bearing capacity and excessive structural displacement. This paper analyzes the accumulation and dissipation rate of excess pore water pressure in the foundation during trial operation, aiming at the super-large displacement of the foundation during the trial operation of an ore yard in Anhui province. The underlying reason of the incident was found out, and a secondary treatment plan for drainage consolidation was proposed. Based on the geotechnical engineering finite element analysis software LinkFEA, the method of strong coupling seepage field and deformation field was used to predict the change process of excess pore water pressure and displacement with or without drainage measures in the foundation. And the predicted results are consistent with the experimental results. The research shows that the amplitude of excess pore water pressure and horizontal displacement in the foundation are larger and the safety is lower in the treatment without drainage plate. After using drainage plate, the excess pore water pressure in the foundation can be greatly reduced, the stability safety factor is greatly improved, and the horizontal displacement is greatly reduced. The excess pore water pressure in the foundation of the drainage slab treatment area is wave-varying in the horizontal direction. The excess pore water pressure in different soil layers in the vertical direction varies greatly and is sensitive to the consolidation coefficient.
作者
吴梦喜
宋世雄
于永军
赵源
WU Meng-xi;SONG Shi-xiong;YU Yong-jun;ZHAO Yuan(Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China;Powerchina Sinohydro Engineering Bureau 8 Co.,Ltd.,Changsha 410004,Huhan,China)
出处
《地基处理》
2022年第6期479-489,共11页
Journal of Ground Improvement
关键词
堆场
排水板
有限元
固结
耦合模拟
oral yard
prefabricated vertical drainage
finite element method
consolidation
coupling numercial simulation
