摘要
目前国内针对重塑软黏土进行大量的研究,得到了许多具有重大意义的成果,然而有关结构性软黏土循环荷载下的动力特性研究却很少。因此,文中通过对杭州结构性软黏土进行了室内循环三轴试验,分析了循环荷载下有效固结围压、振动频率以及动应力比对软化特性的影响。研究结果表明,有效围压对于土体的软化指数有着显著的影响,增大有效围压可以有效减小土体软化指数的发展速率;频率对软化指数衰减影响程度不以线性变化,高频和低频的动荷载激振场会使软黏土产生较明显的软化现象;循环应力比的增加会显著提高土体的软化程度,加快土样的破坏速度。并在试验的基础上建立了饱和软黏土的经验软化模型,并验证了模型的准确性,模型可以为实际工程中地基土层的长期沉降预测以及计算提供了一定理论基础。
At present, a large number of domestic researches have been carried out on remodeling soft clay, and many significant results have been obtained. However, there are few studies on the dynamic characteristics of structural soft clay under cyclic loading. Based on this, this paper conducted indoor cyclic triaxial tests on Hangzhou structural soft clay to analyze the effects of effective consolidation confining pressure, vibration frequency, and cyclic stress ratio(CSR) on degradation characteristics under cyclic loading. The research results show that the effective confining pressure has a significant impact on the degradation index of the soil. Increasing the effective confining pressure can effectively reduce the development rate of the softening index of the soil;the influence of frequency on the attenuation of the degradation does not change linearly. The low frequency dynamic load excitation field will make the soft clay have obvious degradation phenomenon;the increase of the cyclic stress ratio will significantly increase the degradation degree of the soil and accelerate the destruction speed of the soil sample. On the basis of experiments, an empirical degradation model of saturated soft clay is established and the accuracy of the model is verified. The model can provide a theoretical basis for the long-term settlement prediction and calculation of the foundation soil in actual projects.
作者
黄鑫
丁智
孙苗苗
虞建刚
职非韩
黄灿
HUANG Xin;DING Zhi;SUN Miaomiao;YU Jiangang;ZHI Feihan;HUANG Can(College of Civil Engineering and Architecture,Zhejiang University,Hangzhou 310058,China;Department of Civil Engineering,Zhejiang University City College,Hangzhou 310015,China)
出处
《低温建筑技术》
2022年第1期139-143,共5页
Low Temperature Architecture Technology
基金
省级重点研发项目(2020C01102)。
关键词
结构性软黏土
循环荷载
软化特性
软化模型
structural soft clay
cyclic loading
degradation characteristics
degradation model
