高聚物胶凝戈壁土的动模量及阻尼比试验研究  

Tests for dynamic modulus and damping ratio of high polymer cementitious Gobi soil

作　　者：杨海华[1,2,3] 刘亮 刘汉龙[1,2,3,4] 高鹏展 陈育民[2,3] YANG Haihua;LIU Liang;LIU Hanlong;GAO Pengzhan;CHEN Yumin(College of Hydraulic and Civil Engineering,Xinjiang Agricultural University,Urumqi 830052,China;Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering,Hohai University,Nanjing 210098,China;College of Civil and Transportation Engineering,Hohai University,Nanjing 210098,China;School of Civil Engineering,Chongqing University,Chongqing 400045,China)

机构地区：[1]新疆农业大学水利与土木工程学院,乌鲁木齐830052 [2]河海大学岩土力学与堤坝工程教育部重点实验室,南京210098 [3]河海大学土木与交通学院,南京210098 [4]重庆大学土木工程学院,重庆400045

出　　处：《振动与冲击》2023年第3期12-20,共9页Journal of Vibration and Shock

基　　金：国家自然科学基金面上项目(52179101)。

摘　　要：高聚物胶凝戈壁土是将高聚物掺入戈壁土中,可有效提高原状戈壁土的基本性质。采用中型动三轴试验研究了在不同高聚物质量比、围压、固结比、加载频率工况下高聚物胶凝戈壁土的动弹性模量和阻尼比变化规律。结果表明:高聚物质量比R_(p)对动弹性模量和阻尼比影响较大,在动应力比(cyclic stress ratio, CSR)为0.157时,动弹性模量随R_(p)增大呈线性增长;CSR>0.157后随R_(p)增大动弹性模量先增大后减小,在R_(p)为3%时出现峰值;在相同CSR下,天然戈壁土在振动荷载下产生的残余应变比高聚物胶凝戈壁土的大,当R_(p)为3%时经过5次振动后的残余应变仅为天然戈壁土的18.4%;阻尼比随R_(p)的增大略有降低。基于沈珠江动力模型,建立了考虑高聚物质量比影响的修正模型,并通过试验验证了修正模型的适用性。研究成果可为高聚物戈壁土的动力分析和工程应用提供理论依据。High polymer cementitious Gobi soil is a kind of Gobi soil mixed with polymer, it can effectively improve basic properties of undisturbed Gobi soil. Here, dynamic elastic modulus and damping ratio of high polymer cementitious Gobi soil under different polymer mass ratios, confining pressures, consolidation ratios and loading frequencies were studied by using medium dynamic triaxial tests. The results showed that polymer mass ratio R_(p)affects more largely dynamic elastic modulus and damping ratio, when cyclic stress ratio(CSR) is 0.157, dynamic elastic modulus increases linearly with increase in R_(p);when CSR is larger than 0.157, dynamic elastic modulus firstly increases and then decreases with increase in R_(p), and its peak value appears when R_(p)is 3%;under the same CSR, residual strain of natural Gobi soil generated under vibration load is larger than that of high polymer cementitious Gobi soil;when R_(p)is 3%, the latter’s residual strain after 5 vibration cycles is only 18.4% of that of natural Gobi soil;damping ratio decreases slightly with increase in R_(p);based on Shen Zhujiang dynamic model, a modified model considering effects of polymer mass ratio is established, and its applicability is verified with tests;the study results can provide theoretical basis for dynamic analysis and engineering application of high polymer Gobi soil.

关 键 词：高聚物胶凝戈壁土 动三轴试验 动弹性模量 阻尼比 滞回圈 动力模型 

分 类 号：TU43[建筑科学—岩土工程]