基于UHPC板和EPS耗能层的落石冲击力研究  

Study On Rockfall Impact Based on UHPC Plate and EPS Energy Dissipation Layer

作　　者：孙宗磊 杨少军[2] 刘琛[2] 高明昌[2] 吕梁[3] SUN Zonglei;YANG Shaojun;LIU Chen;GAO Mingchang;LÜ Liang(China Railway Economic and Planning Research Institute Co.,Ltd.,Beijing 100038,China;China Railway First Survey&Design Institute Group Co.,Ltd.,Xi'an 710043,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]中国铁路经济规划研究院有限公司,北京100038 [2]中铁第一勘察设计院集团有限公司,西安710043 [3]西南交通大学土木工程学院,成都610031

出　　处：《铁道标准设计》2021年第7期88-92,共5页Railway Standard Design

基　　金：中国铁路总公司科技研究计划项目(N2018G-031);中国铁建股份有限公司科研计划课题(2018-B11)。

摘　　要：艰险山区铁路建设及运营多面临危岩落石风险,常规的落石防护棚洞为RC结构铺设砂土垫层,该结构形式应用时一般为隧道明洞接长或支承于路基基础之上的棚板结构,当其应用于桥隧相连工程时因重力过大而难以实现桥梁棚洞一体化建造。危岩落石防治的桥梁棚洞一体化关键技术在于设法减轻防护棚洞重力,通过试验研究UHPC板铺设EPS耗能层后落石冲击能量与冲击力的关系,旨在通过新型高强材料的应用降低棚洞重力以实现桥梁棚洞一体化技术。研究结果表明:(1)峰值冲击力发生在0.05~0.1s,冲击力随时间呈抛物线形快速增减;(2)冲击能量在50kJ以下时EPS垫层耗能明显,50kJ以上冲击时应避免形成二次峰值冲击;(3)EPS耗能后峰值冲击力增速低于冲击能量的增速,EPS耗能层厚度在70~110cm时耗能变化显著;(4)峰值冲击力与冲击能量的关系为对数函数,拟合的峰值冲击力公式可为同类工程设计提供借鉴。It is difficult to realize the integration of a bridge and a shed tunnel due to the excessive gravity where a bridge is connected with a tunnel.The key of bridge shed tunnel integration for prevention and control of dangerous rock and rockfall is to try to reduce the weight of protective shed tunnel.In this paper,the relationship between impact energy and impact force of falling rock after laying EPS cushion with UHPC plate is studied through experiments,so as to reduce the weight of shed tunnel after the application of new high-strength materials to fulfill the integration of the bridge and the shed tunnel.The research results show that:(1)The peak impact force occurs between 0.05 s and 0.1 s,and the impact force increases and decreases rapidly with time in a parabola shape;(2)When the impact energy is below 50 kJ,the energy consumption of EPS cushion is obvious,and the secondary peak impact should be avoided when the impact energy is above 50 kJ;(3)The increase of peak impact force after EPS energy dissipation is lower than that of impact energy,and the energy consumption changes significantly when EPS thickness is between 70 cm and 110 cm;(4)The relationship between peak impact force and impact energy is a logarithmic function.The formula of peak impact force fitted in this paper can provide reference for the design of similar projects.

关 键 词：山区铁路 落石 冲击荷载 冲击能量 UHPC板 EPS 缓冲材料 耗能 试验 

分 类 号：U458.3[建筑科学—桥梁与隧道工程]