掺有橡胶粉末砂土液化特性的动三轴试验研究  

Dynamic triaxial tests on liquefaction characteristics of rubber-sand mixture

作　　者：李博[1,2] 黄茂松[2] 

机构地区：[1]桂林理工大学广西岩土力学与工程重点实验室,广西桂林541004 [2]同济大学地下建筑与工程系,上海200092

出　　处：《岩土力学》2017年第5期1343-1349,共7页Rock and Soil Mechanics

基　　金：广西岩土力学与工程重点实验室资助课题(No.13-KF-04);浙江省自然科学基金(No.LY17E080012);国家自然科学基金(No.11372228)~~

摘　　要：由于重度小、渗透性强,橡胶粉末常作为边坡、路基和挡土墙的填料,以代替部分砂土,从而提高挡土墙的安全性,并减少砂子的用量。在地震或交通荷载作用下,掺有橡胶粉末的砂土动力学特性,包括应力-应变关系曲线、孔隙水压力累积规律、动剪切模量和抗液化能力方面的研究亟需开展。借助CKC循环动三轴仪,开展饱和不排水条件下掺有橡胶粉末的砂土试样的动力学特性研究,重点评估掺入的橡胶粉末对试样的抗液化性能的影响。研究结果发现,掺有不同粒径橡胶粉末的砂土对应力-应变关系、孔隙水压力的影响非常显著,同时发现,粒径较大的橡胶粉末可以极大地提高试样的抗液化能力。另外,发现掺入量越大,对抗液化能力的提高越明显,且随着掺入量的提高,表现出与常规砂土液化不同的破坏模式。研究结果进一步明确了掺有橡胶粉末的砂土动力特性行为,为橡胶粉末在工程实践中的应用提供了技术依据。最后,对橡胶砂土混合的微观机制进行了解释。Recycled tire wastes mixed with soils are applicable as lightweight filling material for slopes, sub-bases of pavements and retaining walls to improve the safety of the retaining walls. Under the seismic loadings, e.g., earthquake or traffic loads, the dynamic responses of granulated rubber/soil mixtures, such as the evolution of stress-strain, rule of cumulative pore water pressure, dynamic shear modulus, and liquefaction resistance, are essential in the design of such a system. This paper investigates the dynamic responses, liquefaction resistance mainly, of recycled rubber tire powder through mixtures with different tire powder sizes in saturated condition using cyclic triaxial tests. The results show that the larger tire powder size significantly improved liquefaction resistance of granular materials. Meanwhile, the incorporations of tire powder changes the deformation pattern and the evolution of pore water pressure compared to the pure sand. The attempt is to further explain the evolved dynamic behavior of the mixture. And the results as a supplement enrich the database of dynamic behavior of soil rubber mixture as lightweight filling material in saturated condition. Finally, the results are interpreted from the microscopic view of the point.

关 键 词：孔隙水压力累积 橡胶粉末 抗液化能力 循环动三轴试验 

分 类 号：TU473.1[建筑科学—结构工程]