当前位置: X-MOL 学术Comput. Geotech. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Influence of encasement length and geosynthetic stiffness on the performance of stone column: 3D DEM-FDM coupled numerical investigation
Computers and Geotechnics ( IF 5.3 ) Pub Date : 2021-02-03 , DOI: 10.1016/j.compgeo.2020.103993
Zeyu Xu , Ling Zhang , Shuai Zhou

The design of geosynthetic encasement is the most important factor that controls the performance of the geosynthetic-encased stone column (GESC) improved ground, and encasement length (Lenc) and geosynthetic stiffness (J) are two basic design items. Numerous continuum-based numerical models have been proposed to investigate the influence of geosynthetic encasement on the behavior of GESC improved ground, however, the micro-mechanics of stone aggregates cannot be properly simulated due to its discrete nature. In this paper, a three-dimensional discrete element method (DEM) and the finite difference method (FDM) coupled numerical modeling scheme was proposed. Surrounding clay is modeled by the continuum method using FLAC3D and the stone column and geosynthetics are modeled by the discrete element method using PFC3D. The proposed numerical models are validated using laboratory observations. The influence of geosynthetic encasement is analyzed by predicting pressure-settlement behavior, lateral deformation of surrounding clay, stress distribution within the column, and microscopic characteristics of granular materials (i.e., porosity, coordination number and contact force distribution). Numerical results demonstrate that full length and high stiffness encasement will significantly improve the load-bearing capacity of GESCs. In practice, fully-encased stone columns are recommended for reducing the settlement.



中文翻译:

包裹长度和土工刚度对石柱性能的影响:3D DEM-FDM耦合数值研究

土工合成材料外包装的设计是控制土工合成材料包裹石柱(GESC)改良地基性能的最重要因素,而外包装长度(L enc)和土工合成刚度(J)是两个基本设计项目。已经提出了许多基于连续体的数值模型来研究土工合成材料包裹物对GESC改良地面性能的影响,但是,由于其离散性,无法正确地模拟石料的微观力学。提出了三维离散元法(DEM)和有限差分法(FDM)耦合数值建模方案。使用FLAC 3D通过连续介质方法对周围的粘土进行建模利用PFC 3D通过离散单元法对石柱和土工合成材料进行建模。所提出的数值模型通过实验室观察得到了验证。通过预测压力沉降行为,周围粘土的横向变形,柱内应力分布以及粒状材料的微观特征(即孔隙度,配位数和接触力分布)来分析土工合成材料包裹物的影响。数值结果表明,全长和高刚度包裹将显着提高GESC的承载能力。实际上,建议使用全包裹的石柱以减少沉降。

更新日期:2021-02-03
down
wechat
bug