加筋土筋材在拉伸荷载作用下的力学特性  

The Mechanical Characteristics of the Reinforcements under Tensile Load

作　　者：林宇亮[1] 杨果林[1] 李昀[1] 方薇[1] 

机构地区：[1]中南大学土木建筑学院,湖南长沙410075

出　　处：《中国铁道科学》2009年第5期9-14,共6页China Railway Science

基　　金：湖南省科技厅资助项目(06ck3030);湖南省交通厅资助项目(200612)

摘　　要：通过拉伸试验,研究网格直径分别为2.2和2.7 mm的双绞合六边形金属格宾网、70RE和80RE土工格栅4种筋材拉伸力学性能。得出4种筋材的拉伸强度、最大负荷下伸长率等力学性能指标以及单位宽度拉伸力与伸长率的关系特征曲线。根据筋材实体工程中的受力特性,推导出筋材约束变形方程。结果表明,格宾网在发生钢丝断裂之后仍呈现出较强的抗拉性能,大直径格宾网体现出优越的力学性能;80RE土工格栅的力学性能优于70RE土工格栅;修正后的格宾网的单位宽度拉伸力与伸长率的关系曲线仍呈现弹性、屈服和强化3个阶段;在约束条件下,筋带的变形量与筋带的割线模量、应力水平、筋带在加筋体中主动区和稳定区的长度等因素有关。Tensile tests were carried out to determine tensile mechanical characteristics of four materials： 2.2 and 2.7 mm double twisted hexagonal wire gabion meshes,70RE geogrid and 80RE geogrid.Through tests,the mechanical performance indexes such as the tensile strength,unit elongation under the maximum load and the curves between tension per unit width and unit elongation were obtained.Based on the mechanical characteristics of the reinforcement when buried in the soil,the constraint deformation equation was deduced.The results show that the gabion meshes present good tensile characteristics in the event of the rupture of the meshes. The larger-diameter gabion mesh shows a better mechanical performance, and the mechanical performance of 80RE geogrid is superior to that of 70RE geogrid. The revised relationship curves between the tension per unit width and unit elongation also present elastic stage, yield stage and strength stage. The constraint deformation of reinforcement is influenced by factors such as secant modulus of materials, stress levels, and the length of reinforcement in active area and stable area.

关 键 词：双绞合六边形金属格宾网 土工格栅 力学特性 拉伸试验 

分 类 号：U213.152.2[交通运输工程—道路与铁道工程]