基于离散元的强夯法加固珊瑚礁砂地基机理分析  

Mechanism Analysis of Strengthening the Coral Reef Sand Foundation by Dynamic Compaction Method Based on Discrete Element Theory

作　　者：王建平 安韶 方斌 WANG Jianping;AN Shao;FANG Bin(Naval Research Institute,Beijing 100071,China)

机构地区：[1]海军研究院,北京100071

出　　处：《工业建筑》2024年第10期199-204,共6页Industrial Construction

基　　金：国家重点研发计划项目(2019YFC1509704);国家自然科学基金项目(41877218)。

摘　　要：强夯法加固地基具有效果显著、材料节省、工期短等优点,适用于珊瑚礁砂地基加固。为研究强夯法加固珊瑚礁砂地基机理,基于离散元既可以模拟珊瑚礁砂形状、又能较好地模拟强夯过程中土体孔隙率变化的特点,建立强夯法加固珊瑚礁砂地基的数值模型,并通过现场试验结果验证了数值模型的可靠性,最后通过模型分析不同夯击能作用下珊瑚砂的颗粒破碎过程、力链发展与地基沉降,明晰了地基加固的内在机理。研究结果表明:采用的离散元数值模型地基沉降结果与现场夯击试验结果具有较好的一致性,模型误差小、可信度高;强夯作用下,珊瑚砂颗粒孔隙减小,颗粒破碎带逐渐向夯坑两端发展,力链向夯击坑中心集中且呈放射状分布;夯击能越大,地表与地基一定深度范围内沉降越大,颗粒破碎带及力链均沿深度与广度两个方向发展。The dynamic compaction method for reinforcing foundation has the advantages of significant effectiveness,saving in materials and short construction period,which is suitable for reinforcing coral reef sand foundation.To conduct the mechanism of strengthening coral reef sand foundation by dynamic compaction method,a numerical model was established based on discrete element method which could simulate both the shape of coral reef sand and the characteristics of soil porosity changes during the dynamic compaction process.The numerical model reliability was verified by field test results,and finally the coral reef sand particle crushing process,force chain development and foundation settlement under different tamping energy were analyzed,so as to clarify the internal mechanism of foundation reinforcement.The research results showed that the foundation settlement of adopted discrete numerical model showed a good alignment with that of field results,proving that the model had low error and high reliability;under the action of dynamic compaction method,the pores of coral reef particles decreased,the particle fragmentation zone gradually developed to both ends of the ramming pit,and the force chain was concentrated and radially distributed towards the center of the ramming pit;the greater the tamping energy,the greater the surface and foundation settlement within a certain depth range,and the particle fragmentation zone and force chain developed in both depth and breadth.

关 键 词：离散元 强夯法 珊瑚礁砂 地基加固 机理分析 

分 类 号：TU472.31[建筑科学—结构工程] U655.54[建筑科学—土工工程]