循环荷载下纳米SiO_(2)改良水泥土动变形研究及微观分析  

Research on Dynamic Deformation of Nano-SiO_(2)-Improved Cement-Soil Under Cyclic Loading and Its Microstructure Analysis

作　　者：庄心善 寇强 ZHUANG Xinshan;KOU Qiang(School of Civil Engineering,Architecture and Environment,Hubei University of Technology,Wuhan 430068,China)

机构地区：[1]湖北工业大学土木建筑与环境学院,武汉430068

出　　处：《工业建筑》2022年第5期169-173,218,共6页Industrial Construction

基　　金：国家自然科学基金项目(51708190)。

摘　　要：运用GDS真/动三轴仪和PQ001型低磁场核磁共振分析仪探究纳米SiO_(2)改良水泥土的动力特性及其内部孔隙变化。动力特性试验结果表明:水泥土的动应力-动应变曲线随纳米SiO_(2)掺量增加先上移后下降,动变形模量-动应变曲线、同级荷载滞回曲线圈面积、阻尼比-动应变曲线随着纳米SiO_(2)掺量增加先下降后上移,在纳米SiO_(2)掺量为2.5%时,水泥土抵抗动荷载能力最强;孔结构分析得出纳米SiO_(2)改良水泥土的内部孔隙结构得到改善,强度提高。推荐纳米SiO_(2)最优掺量为2.5%。The dynamic characteristics of nano-SiO_(2)-improved cement-soil and the change of internal micro-pore structure of nano-SiO_(2)-improved cement-soil were studied with the dynamic triaxial test apparatus of GDS and the nuclear magnetic resonance test apparatus PQ001.The dynamic triaxial test results showed that the σ;-ε;curve of cement-soil first rising and then decline with the increase of the nano-SiO_(2)content. The curve of the dynamic deformation modulus and dynamic strain, the area surrounding by the hysteresis curve under the same level load, and the curve for damping ratios and dynamic strain of cement-soil first decline and then rising with the increase of the nano-SiO_(2)content. When the nano-SiO_(2)content was 2.5%, the dynamic resistance of cement-soil was maximun. Micro structure analysis of cement-soil showed that the pore structure and strength of nano-SiO_(2)-improved cement-soil were increased. The optimal nano-SiO_(2)content was 2.5%.

关 键 词：水泥土 纳米SiO_(2) 动力特性试验 孔结构分析 

分 类 号：TU41[建筑科学—岩土工程]