摘要
为探究加筋砾性土在循环荷载作用下的累积应变及动力特性,选取不同围压、动应力幅值和加筋层数工况下对加筋砾性土试样进行固结不排水动三轴试验,采用灰色关联分析(GRA)方法,分别研究加筋砾性土的累积轴向塑性应变、回弹模量与影响因素围压、动应力幅值和加筋层数之间的关联度大小。研究表明:加筋砾性土的累积塑性应变随振次的发展趋势符合稳定性增长规律,增大围压和提高加筋层数能够显著减少其累积塑性应变,而较大的动应力幅值将会导致土体的动回弹模量升高,土体的吸能效果降低,不利于抗震;基于GRA理论以及相关度系数计算结果,得出循环荷载作用下影响土体累积塑性应变、回弹模量两者发展规律的优势子因素,且以回弹模量作为加筋砾性土在循环荷载作用下的力学响应性指标能够综合考虑围压、动应力水平及加筋层数的贡献程度,可信度较高。
To investigate reinforced gravel soil under cyclic loading is the accumulation of strain and the dynamic characteristics, the selection of different confining pressure, the dynamic stress amplitude and reinforced layers of reinforced gravel under the condition of the soil specimen consolidation undrained dynamic triaxial test, using the method of grey relational analysis(GRA), respectively study the accumulation of reinforced gravel soil axial plastic strain, modulus of resilience and influencing factors of confining pressure, dynamic stress amplitude correlation between size and reinforced layer. The results show that the cumulative plastic strain of the reinforced gravel soil increases with the trend of vibration times, and the cumulative plastic strain can be significantly reduced by increasing the confining pressure and increasing the number of reinforced layers. The larger dynamic stress amplitude will lead to the increase of the dynamic rebound modulus of the soil and the decrease of the energy absorption effect of the soil, which is not conducive to seismic resistance. Based on the results of the GRA theory and correlation coefficient, the dominant subfactors influencing the development of the cumulative plastic strain and the rebound modulus of the soil under cyclic loading are derived. The rebound modulus as the mechanical responsiveness index of reinforced gravelly soil under cyclic loading can take into account the contribution of the surrounding pressure, the dynamic stress level and the number of reinforced layers, which is more reliable.
作者
王家全
董程锋
周圆兀
林志南
WANG Jiaquan;DONG Chengfeng;ZHOU Yuanwu;LIN Zhinan(School of Civil and Architectural Engineering,Guangxi University of Science and Technology,Liuzhou 545006,China;Guangxi Zhuang Autonomous Region Engineering Research Center of Geotechnical Disaster and Ecological Control,Guangxi University of Science and Technology,Liuzhou 545006,China)
出处
《土木工程与管理学报》
2022年第1期29-34,49,共7页
Journal of Civil Engineering and Management
基金
国家自然科学基金(41962017)
广西自然科学基金(2017GXNSFAA198170)
广西高等学校高水平创新团队及卓越学者计划项目(桂教人才[2020]6号)
广西研究生教育创新计划项目(YCSW2021310)。
关键词
循环荷载
加筋土
灰色理论
累积塑性应变
动力特性
cyclic loading
reinforced soil
grey theory
cumulative plastic deformation
dynamic characteristics
