客运专线基床底层砾石土填料物理力学性质试验研究  

Experimental Research on Physical and Mechanical Properties of Gravelly Soil Filling the Base Course of the Subgrade Bed of Passenger Dedicated Line

作　　者：陈坚[1] 罗强[1] 陈占[2] 杨尧[1] 张云根[1] 

机构地区：[1]西南交通大学高速铁路线路工程教育部重点实验室,四川成都610031 [2]中铁第四勘察设计院集团有限公司,湖北武汉430063

出　　处：《铁道学报》2011年第7期91-97,共7页Journal of the China Railway Society

基　　金：国家自然科学基金资助项目(50838006);西南交通大学创新团队培育计划(2007IRT06);中铁第四勘察设计院集团有限公司科技开发计划项目(2006K29-1)

摘　　要：对取自武汉—广州客运专线路基基床底层的砾石土填料开展颗粒分析、相对密度、多种击实、大型剪切/压缩/渗透等粗粒土特种土工试验。得到以下结论:(1)粗细颗粒含量适当的无黏性砾石土填料,较易形成密实骨架结构,从而获得优良力学性能,并表现出较好的可压实性;(2)良好级配的砾石土填料,对应规范要求孔隙率的压实系数偏低,采用压实系数作为控制指标更为严格、可靠;(3)运用构建的"模量折减率法"和"卸载回弹率法"分析发现,压实系数0.90和0.95分别对应骨架疏松和密实土体结构状态,并在强度、变形和渗透性能等方面差异明显。Particle analysis,relative density tests,multi-type compaction tests,large-size shear tests,large-size compression tests and large-size permeability tests were made with the gravel filler taken out from the base course of the subgrade bed Wuhan-Guangzhou Passenger Dedicated Line.The results were as follows： Gravel filler with suitable amounts of coarse and fine particles is easier to form dense skeleton structures and to achieve excellent mechanical properties and good compaction features;for the well-graded gravel filler,the compaction coefficient corresponding to the porosity specified in norms is low,so it is more appropriate and reliable to use the compaction coefficient as the control index;using the method of reduction factor of initial tangent shear modulus and the method of unloading rebound rate presented by the author,it is found that the compaction factor k=0.90 and k=0.95 correspond to the dense skeleton structure and loose skeleton structure respectively,and the two types of soil structures behave significantly different in strength,deformation and permeability.

关 键 词：客运专线 砾石土填料 骨架结构 压实特性 模量折减率 卸载回弹率 

分 类 号：U448.13[建筑科学—桥梁与隧道工程]