Energy allocation based design approach for rockfall protection barriers

• 作 者: Hu Xu Cristina Gentilini Zhixiang Yu Xin Qi Shichun Zhao
• 机 构: School of Civil Eng., Southwest Jiaotong University, Chengdu, 610031 Sichuan, China;DICAM Department
• 出 处: 第五届土木与防灾——跨领域整合研讨会
• 发表日期: 2017年10期
• 关键词: rockfall protection barrier energy allocation structural design steel wire-ring

　　This paper proposes an effective design approach for quickly determining the specification,size and amount of components of the typical flexible rockfall protection barrier structure.It is based on a reliable numerical modelling validated by many experimental tests that include both component tests and the full-scale impact test.The interception component made up of steel wire-ring net was particularly investigated through 12 groups of one-ring and three-ring specimen tests,to define a revised constitutive model and a failure criterion based on effective plastic strain,which were verified by both in-plane and out-of-plane quasi-static tests of the net specimen.The accuracy of the numerical strategy for overall barrier structure was validated by a full-scale in-site test with the nominal energy level of 1500kJ,following the guidelines include SEL and MEL impacts.It is discussed that the total impact energy is simultaneously consumed by different ways,in which the internal energy takes a significant ratio so that it can be assumed to consume all energy conservatively in design.The proportion of the internal energy of each component is explored and defined.Besides,the internal forces with sufficient reservation are presented.The proposed design procedure,applied to a barrier structure with the nominal energy level of 3500kJ,is testified by a new corresponding full-scale impact test,proving the design approach rational and secure.