基于DDA方法的排碴井筒堵塞概率分析  

Probability Analysis of the Mucking Shaft Blockage Based on Discontinuous Deformation Analysis

作　　者：阳生权[1] 周云锋 吕中玉 彭程武 YANG Shengquan;ZHOU Yunfeng;LÜZhongyu;PENG Chengwu(School of Civil Engineering,Hunan University of Sciences and Technology,Xiangtan Hunan 411201,China;Guangxi Road and Bridge Engineering Group Co.Ltd.,Nanning 430071,China)

机构地区：[1]湖南科技大学土木工程学院,湖南湘潭411201 [2]广西路桥工程集团有限公司,广西南宁530200

出　　处：《湖南工业大学学报》2023年第1期16-21,共6页Journal of Hunan University of Technology

基　　金：广西重点研发计划基金资助项目(桂科AB18050013)。

摘　　要：依托某公路隧道的超大直径通风竖井工程,针对通风竖井施工中心小直径井筒排碴存在极大堵塞风险、严重影响建设工期的问题,考虑到井筒落石属于非连续变形动力学过程,因此,采用非连续变形分析(DDA)方法,通过对井筒落石进行数值建模,以球体作为基本块体单元,基于捆绑算法将球颗粒捆绑成相应形状块体,模拟块体运动过程中的碰撞、摩擦等,开展了针对性的小直径井筒落石堵塞概率分析。数值模拟结果表明,为避免小直径排碴井筒发生堵塞现象,应严格控制抛入排碴井筒的岩块尺寸与块度;钻爆法施工的小直径排碴井筒超欠挖现象越严重,井筒堵塞概率越大。模拟结果较为真实地反映了排碴井工况的工程实际。Taking the super large diameter ventilation shaft project of a highway tunnel as the research object,in view of the great risk of blockage and serious effect on the construction period of the small-diameter shaft mucking in the ventilation shaft construction center,considering a discontinuous deformation dynamic process of the shaft rockfall,a targeted probability analysis of small diameter wellbore rockfall blockage has been carried out by adopting the discontinuous deformation analysis(DDA)method based on a numerical modeling of wellbore rockfall,taking sphere as the basic block unit,with ball particles bound into blocks of corresponding shape by using the binding algorithm,followed by a simulation of the collision and friction during block movement.The numerical simulation results show that in order to avoid the blockage of the small diameter mucking shaft,the size of the rocks and the size of the blocks thrown into the mucking shaft must be strictly controlled;the more serious the over excavation and under excavation of the small diameter mucking shaft constructed by drilling and blasting method,the greater the blockage probability will be.The simulation results truly reflect the engineering practice of the working condition of the mucking shaft well.

关 键 词：公路隧道 通风竖井 非连续变形分析(DDA) 小直径排碴井 堵塞概率 数值分析 

分 类 号：U455.8[建筑科学—桥梁与隧道工程]