水泥和SH固化剂复合改性风积沙路基土动力特性研究  

Study on the dynamic characteristics of composite modified aeolian sand roadbed soil with cement and SH curing agent

作　　者：郭德尚 房建宏 王青志 GUO Deshang;FANG Jianhong;WANG Qingzhi(School of Civil Engineering and Water Resources,Qinghai University,Xining 810016,China;Qinghai Research Institute of Transportation,Xining 810016,China)

机构地区：[1]青海大学土木水利学院,青海西宁810016 [2]青海省交通科学研究院,青海西宁810016

出　　处：《青海大学学报》2024年第3期71-76,103,共7页Journal of Qinghai University

基　　金：国家自然科学基金项目(42161026);青海省科学技术厅项目(2021-ZJ-716);青海大学中青年科研基金项目(2022-QGY-5)。

摘　　要：为研究水泥与SH固化剂复合改性沙漠风积沙的动力特性,以水泥和SH固化剂为材料,以最优含水率为定值,研究复合固化材料含量对试验土体的影响。本实验共制试样26组,每组3个试样,开展了固结不排水振动三轴试验和核磁共振试验,分析了2种材料的复合固化机理及力学特性;通过核磁共振试验揭示掺入SH固化剂后试样的微观孔隙变化规律,从而对固化剂的改良效果进行评价。结果表明:(1)单一水泥固化效果比2种固化材料复合固化土体的效果较差。2种固化材料复合能起到较好的固化效果,固化后的土体内部结构更为稳固。(2)掺量为11%的水泥和0.5%的SH固化剂的固化效果在所有工况下为最优。(3)单掺水泥后土体的应力应变曲线表现为应变软化型,加入SH固化剂后应力应变曲线表现为应变硬化型。研究结果可以为沙漠地区公路建设提供理论依据。To explore the dynamic characteristics of composite modified desert aeolian sand with cement and SH curing agent,cement and SH curing agent are taken as materials and the optimal moisture content as a constant value to study the effects of composite curing material content on the experimental soil.A total of 26 group of specimens are prepared,with 3 samples in each group.The consolidated undrained vibration triaxial test and nuclear magnetic resonance(NMR)test are conducted to analyze the composite curing mechanism and mechanical properties of the two materials.The microscopic pore variations of specimen are revealed by using NMR test after adding SH curing agent to evaluate the improvement effects of the curing agent.The results show that:(1)The effect of single addition of cement is worse than that of two curing materials.The combination of two materials can play a better curing effect when the solidified soil has a more stable internal structure.(2)The curing effect of 11%cement and 0.5%SH curing agent is the best under all working conditions.(3)The stress-strain curve of the soil after single addition of cement shows a strain softening type,while the stress-strain curve shows a strain hardening type after adding SH curing agent.The research results can provide theoretical basis for highway construction in desert areas.

关 键 词：风积沙 水泥 SH固化剂 核磁共振 路基工程 

分 类 号：U416[交通运输工程—道路与铁道工程]