土工格栅加筋橡胶碎石动力特性试验研究
Experimental study on dynamic properties of geogrid reinforced rubber gravel
蔡永明 1王志杰 2齐逸飞 1杨广庆 2王贺2
作者信息
- 1. 石家庄铁道大学省部共建交通工程结构力学行为与系统安全国家重点实验室,河北石家庄 050043;石家庄铁道大学土木工程学院,河北石家庄 050043
- 2. 石家庄铁道大学省部共建交通工程结构力学行为与系统安全国家重点实验室,河北石家庄 050043;石家庄铁道大学土木工程学院,河北石家庄 050043;石家庄铁道大学道路与铁道工程安全保障省部共建教育部重点实验室,河北石家庄 050043
- 折叠
摘要
土工格栅加筋是提升橡胶碎石混合料承载能力的重要方式.为探究土工格栅加筋橡胶碎石复合体动力特性及其作用机制,基于分级循环荷载作用下大型三轴试验,对3种代表性橡胶掺量碎石混合料进行不同层数土工格栅加筋,分析其累积塑性应变、滞回曲线发展演化规律,对比动弹性模量、阻尼比等动力特性关键参数,探讨耦合作用影响机制.研究结果表明:同级动应力作用下土工格栅加筋可减缓累积塑性应变的增大,随着加筋层数的增多,加筋效果更为明显;橡胶掺量增加可提升试样延性,但导致承载能大幅降低,不利于筋材加筋效果的发挥;滞回曲线形态主要取决于橡胶掺量,随着橡胶掺量增加,其形态更加饱满、倾斜,其排列更加稀疏;土工格栅加筋可提升复合体动弹性模量,并随筋材层数增多呈现出明显增长阶段;橡胶掺量对阻尼比初始值以及变化趋势产生主要影响.
Abstract
Geogrid is an important way to improve the bearing capacity of rubber gravel mixture.The dynamic characteristics and mechanism of geogrid-reinforced rubber gravel composites were investigated through large-scale triaxial tests.These tests involved graded cyclic loading with different layers of geogrids and were conducted using three representative rubber contents of gravel mixtures.The study focused on analyzing the development and evolution laws of cumulative plastic strain and hysteresis curves.Key parameters of dynamic characteristics,such as dynamic elastic modulus and damping ratio were compared.The influence mechanism of the coupling effect between geogrid reinforcement and rubber gravel mixtures was also discussed.The results showed that geogrid reinforcement could slow down the increase of cumulative plastic strain under the same dynamic stress.This effect became more pronounced with an increasing number of geogrid layers.Additionally,increasing the rubber content in the mixture improved the ductility of the specimen,but it greatly reduced the bearing energy of the reinforced composite.The shape of the hysteresis curve was primarily influenced by the rubber content,becoming more full,inclined,and its arrangement becoming sparser as the rubber content increased.Geogrids improved the dynamic elastic modulus of the specimens,showing a significant growth stage with an increasing number of geogrid layers.The rubber content had a major impact on the initial value and change trend of the damping ratio.These findings provide valuable insights into the behavior and performance of geogrid-reinforced rubber gravel composites under dynamic loading conditions.They contribute to the understanding of how geogrids can enhance the bearing capacity and improve the overall stability of engineering structures constructed with rubber gravel mixtures.
关键词
土工格栅/橡胶碎石/加筋层数/动力特性/大型三轴试验Key words
geogrid/rubber gravel mixture/number of reinforcement layer/dynamic characteristic/large-scale triaxial tests引用本文复制引用
基金项目
国家自然科学基金(51709175)
国家重点研发计划(2022YFE0104600)
河北省高等学校科学技术研究项目(BJ2020045)
出版年
2024
国家科技期刊平台
NSTL
维普
万方数据