摘要
为了探究正弯矩循环荷载对管片接头力学性能的影响,以某地铁线单层衬砌管片接头为研究对象,建立三维精细化的盾构管片接头数值模型,在与已有单向正弯矩下管片接头力学破坏试验对比验证的基础上,开展单向正弯矩循环加载下管片接头全过程破坏数值模拟,研究管片接头破坏模式、滞回曲线、骨架曲线、刚度退化以及耗能能力等,并进一步探讨轴力和螺栓预紧力对管片接头循环力学性能的影响规律。研究结果表明:1)管片接头在单向正弯矩循环加载作用下的破坏过程可划分为5个阶段,即弹性阶段、塑性硬化阶段、承载力第1次下降阶段、平台阶段及第2次下降破坏阶段;2)循环加载显著降低了管片接头的承载能力,并存在明显的强度与刚度下降等损伤累积特征;3)轴力减弱了接头滞回曲线的捏拢效应,提高了峰值弯矩及延性性能,而螺栓预紧力对接头滞回曲线捏拢效应影响较小,并会降低接头峰值弯矩和提高接头延性性能。
To investigate the impact of positive bending moment cyclic loads on the mechanical properties of segment joints under seismic conditions,a refined three-dimensional numerical model of single-layer lining pipe segment joints from a certain subway line was established.This model underwent validation through comparison with mechanical failure tests conducted on pipe segment joints subjected to unidirectional positive bending moments.Subsequently,a comprehensive numerical simulation of the entire failure process of pipe segment joints under cyclic loading with unidirectional positive bending moments was conducted.The study focused on the cyclic mechanical properties aspects such as failure modes,hysteresis behavior,skeleton behavior,stiffness degradation,and energy dissipation capacity of segment joints.Furthermore,it delved into the impact patterns of axial force and bolt preloading on the cyclic mechanical properties of these joints.Results show that pipe segment joints,under cyclic loading with unidirectional positive bending moments,exhibit a five-stage failure phases:elastic,plastic hardening,initial load reduction,plateau,and secondary decline.Cyclic loading significantly diminishs the load-bearing capacity of pipe segment joints,exhibiting evident characteristics of damage accumulation,including substantial decreases in strength and stiffness.Axial force reduces the pinching effect of the joint's hysteresis curve,enhancing peak moment and ductility performance.Conversely,bolt preloading has minimal impact on the pinching effect of the hysteresis curve,reducing the peak moment of pipe segment joints but increasing joint ductility.
作者
赵旭
谢伟杰
黄景琦
张泽彬
杜修力
赵密
曹胜涛
张凤琳
ZHAO Xu;XIE Weijie;HUANG Jingqi;ZHANG Zebin;DU Xiuli;ZHAO Mi;CAO Shengtao;ZHANG Fenglin(Key Laboratory of Urban Security and Disaster Engineering,Ministry of Education,Beijing University of Technology,Beijing 100124,China;Beijing Municipal Key Laboratory of Urban Underground Space Engineering,University of Science and Technology Beijing,Beijing 100083,China;Guangzhou Yingli Technology Co.,Ltd.,Guangzhou 510700,China)
出处
《北京工业大学学报》
北大核心
2025年第9期1080-1091,共12页
Journal of Beijing University of Technology
基金
国家自然科学基金资助项目(52378475,41672289)。
关键词
管片接头
正弯矩
循环加载
力学性能
数值模拟
损伤累积
segment joint
positive bending moment
cycle loading
mechanical property
numerical simulation
damage accumulation
