摘要
砂土小应变条件下动力特性的细观分析是解决工程微振动实践问题的重要依据。越来越多的大型基础设施的建设导致高压条件下,砂土的动力特性会因为颗粒材料状态的变化而发生改变。通过Ottawa砂、福建砂、粉煤灰三种不同颗粒材料在高压条件下应力应变、剪切波速、压缩波速以及侧向土压力系数等土力学参数的演化过程,对砂性颗粒的动力特性进行研究。研究结果表明,三种砂性颗粒在7 MPa左右压力下会产生破碎;颗粒的剪切波速和压缩波速会随着压力的增加而增加。侧向土压力系数在加载过程中增量较小;但是在卸载时会随着压力的减小而大幅增加;同时验证了弯曲压缩元可以在高压条件下可以正常工作。
The microscopic analysis of sand dynamic characteristics is an important factor for slightly vibration engineering practice. Sand’s mechanical characteristics would change with the difference of the condition of particle materials under high pressure caused by more and more large infrastructure constructions. Ottawa,Fuzhou standard sand,fly ash are used;and the evolution of stress-strain curve,shear wave velocity,compressional wave velocity and coefficient of lateral pressure is measured to study the dynamic characteristics of particle materials. The results show that particle crushing would happen at 7 MPa. Shear wave velocity or compressional wave velocity would increase with the increase of loading pressure;coefficient of lateral pressure slightly increases at the loading stage;and it would quickly increase with the decrease of axial pressure at the unloading stage.
作者
张海涛
ZHAN Hai-tao(China Railway Siyuan and Design Group Co.,Ltd,Wuhan 430063,China)
出处
《科学技术与工程》
北大核心
2019年第2期192-199,共8页
Science Technology and Engineering
关键词
颗粒材料
颗粒破碎
一维压缩
波速
侧向土压力系数
particle materials
particle crushing
one-dimensional compression
wave velocity
coefficient of lateral pressure
