铁路荷载下平潭滨海相软土动力变形及强度特性试验研究  

Experimental study on dynamic deformation and strength characteristics of Pingtan coastal soft soil under railway loading

作　　者：岳长辉 Yue Changhui(China Railway 18th Bureau Group Municipal Engineering Co.,Ltd.,Tianjing 300350,China)

机构地区：[1]中铁十八局集团市政工程有限公司,天津300350

出　　处：《工程勘察》2024年第3期1-7,共7页Geotechnical Investigation & Surveying

基　　金：国家自然科学基金资助项目(11662007)。

摘　　要：平潭地区滨海相软土渗透性低、结构性较强,目前对其动变形特性研究较少,基于该现状,以福平铁路路基工程为研究背景,利用GDS动三轴系统展开循环动应力试验,研究不同频率、围压及动应力幅值下平潭滨海相软土动变形特性变化规律。试验结果表明滨海相软土动弹性模量随频率、围压提高而增大,采用修正Kondner模型能较好拟合动弹性模量倒数随动应变的变化关系,建立最大动弹性模量归一化模型,研究不同频率、围压下滨海相软土动强度变化规律,分析不同破坏振次下土体抗剪强度指标,结果可为相关工程及研究提供重要基础数据与参考。The coastal soft soil in Pingtan area has low permeability and strong structure,while there are few researches on its dynamic deformation characteristics.Based on this situation,the cyclic dynamic stress tests are carried out by using GDS dynamic triaxial system with the research background of Fuping Railway roadbed,and the changes of dynamic deformation characteristics of Pingtan coastal soft soil under different frequencies,confining pressure and dynamic stress amplitude are studied.The experimental re-sults show that the dynamic elastic modulus of the coastal soft soil increases with the increase of the fre-quency and confining pressure.The modified Kondner model can be used to fit the reciprocal dynamic e-lastic modulus with the change of dynamic strain,and the normalization model of maximum dynamic elastic modulus is established.The dynamic strength of the coastal soft soil under different frequency and confi-ning pressure are also studied,and the shear strength index of the soil under different failure vibration times is analyzed.The results could provide important basic data and reference for related engineering and research.

关 键 词：滨海相软土 动力变形 动弹性模量 动应力 路基填筑 

分 类 号：TU441[建筑科学—岩土工程]