纳米CaCO_(3)影响下重塑软黏土动力特性及微观孔隙结构研究  

Dynamic characteristics and microscopic pores structure of remolded soft clay under influence of nano-CaCO_(3)

作　　者：庄心善 张子涵 ZHUANG Xinshan;ZHANG Zihan(School of Civil Engineering and Architecture,Hubei University of Technology,Wuhan,Hubei 430068,China)

机构地区：[1]湖北工业大学土木建筑与环境学院,湖北武汉430068

出　　处：《河北科技大学学报》2024年第5期539-548,共10页Journal of Hebei University of Science and Technology

基　　金：国家自然科学基金(51978248)。

摘　　要：为研究循环荷载下纳米CaCO_(3)重塑软黏土的动力特性与微观形态,进行GDS动三轴、NMR试验,分析其动应力-动应变、动弹性模量、阻尼比及微观孔隙变化规律。结果表明:随着纳米CaCO_(3)掺量增加、围压增大,软黏土的动应变逐渐减小,动弹性模量逐渐增大;固结应力比增大使纳米CaCO_(3)重塑软黏土动应变先减小后增大,动弹性模量先增加后减小;围压和固结应力比的提高均可有效降低软黏土的阻尼比;软黏土滞回耗能与动应变呈现明显的非线性关系;纳米CaCO_(3)重塑软黏土T2分布曲线主峰峰值及峰面积相比于素软黏土显著降低,孔隙比减小使土体结构更加稳定。所进行的纳米CaCO_(3)重塑软黏土动力特性研究,可为实际工程提供参考。To study the dynamic characteristics and microstructure of nano-CaCO_(3) remolded soft clay under cyclic loading,GDS dynamic triaxial and NMR tests were conducted to analyze its dynamic stress-strain,dynamic elastic modulus,damping ratio,and micro pore changes.The results show that as the content of nano-CaCO_(3) increases and the confining pressure increases,the dynamic strain of the remolded soft clay gradually decreases and the dynamic elastic modulus gradually increases;The increase in consolidation stress ratio leads to a decrease and then an increase in dynamic strain of nano-CaCO_(3) remolded soft clay,and an increase and then a decrease in dynamic elastic modulus;The increase in confining pressure and consolidation stress ratio can effectively reduce the damping ratio of the soft clay;There is a significant nonlinear relationship between the hysteresis energy dissipation of soft clay and the dynamic strain curve;The main peak and peak area of the T 2 distribution curve of nano-CaCO_(3) soft clay are significantly reduced compared to plain soft clay,and the decrease in pore ratio makes the soil structure more stable.The obtained dynamic characteristics of remolded soft clay based on nano-CaCO_(3) provides some reference for practical engineering.

关 键 词：地面工程 重塑软黏土 纳米CaCO_(3) 循环荷载 固结应力比 动弹性模量 阻尼比 

分 类 号：TU443[建筑科学—岩土工程]