全风化花岗岩路基填料改良试验研究  

Experimental Study on Improvement of Completely Weathered Granite Subgrade Filler

作　　者：苏钰钦 王芳 欧尔峰[3] 马路寒 SU Yuqin;WANG Fang;OU Erfeng;MA Luhan(School of Transportation,Lanzhou Jiaotong University,Lanzhou 730070,China;Engineering Management Center,CHINA RAILWAY,Beijing 100038,China;School of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China;Beijing Engineering Consultants Ltd.,Beijing 100038,China)

机构地区：[1]兰州交通大学交通运输学院,兰州730070 [2]中国国家铁路集团有限公司工程管理中心,北京100038 [3]兰州交通大学土木工程学院,兰州730070 [4]北京市勘察设计研究院有限公司,北京100038

出　　处：《铁道建筑》2023年第1期132-136,共5页Railway Engineering

摘　　要：海南地区全风化花岗岩广泛分布,却无法直接用作路基填料。针对这一问题,对全风化花岗岩采用水泥进行改良,同时开展界限含水率、重型击实、加州承载比(California Bearing Ratio,CBR)、无侧限抗压强度、回弹模量、动三轴试验研究素土及改良土工程特性。结果表明:随着水泥掺量增加,塑性指数递减,最优含水率和最大干密度均呈线性递增趋势;随着水泥掺量的增大,CBR值、无侧限抗压强度、回弹模量和动应力大幅增长,改良土工程性质显著提升。根据试验成果,建议基床表层采用水泥掺量6%的全风化花岗岩改良土,基床底层及基床以下路基采用水泥掺量4%的改良土。Completely weathered granite was widely distributed in Hainan Province,but it could not be directly used as subgrade filler.To solve this problem,the completely weathered granite was improved by cement,and the engineering characteristics of plain soil and improved soil were studied by boundary moisture content,heavy compaction,California Bearing Ratio(CBR),unconfined compressive strength,resilience modulus and dynamic triaxial test.The results show that with the increase of cement content,the plasticity index decreases,and the optimum moisture content and maximum dry density both show a linear increasing trend.With the increase of cement content,the CBR value,unconfined compressive strength,resilience modulus and dynamic stress increased significantly,and the engineering properties of improved soil improved significantly.According to the test results,it is recommended that the completely weathered granite improved soil with 6% cement content be used for the surface layer of the subgrade bed,and the improved soil with 4% cement content be used for the bottom layer of the subgrade bed and the subgrade below the subgrade bed.

关 键 词：高速铁路 路基 现场试验 全风化花岗岩 填料 水泥 掺量 改良 

分 类 号：U416[交通运输工程—道路与铁道工程]