基于PFC的基坑爆破数值模拟及安全性分析  

Numerical simulation and safety analysis of foundation pit blasting based on PFC

作　　者：罗仁宇 李奇志 黄云进 杨耿超 余毛毛 祖公博 姚清河 LUO Renyu;LI Qizhi;HUANG Yunjin;YANG Gengchao;YU Maomao;ZU Gongbo;YAO Qinghe(School of Aeronautics and Astronautics,Sun Yat-sen University,Shenzhen 518107,China;China Construction Second Engineering Bureau South China Branch,Shenzhen 518048,China)

机构地区：[1]中山大学航空航天学院,广东深圳518107 [2]中建二局华南分公司,广东深圳518048

出　　处：《中山大学学报（自然科学版）（中英文）》2023年第5期107-114,共8页Acta Scientiarum Naturalium Universitatis Sunyatseni

基　　金：中建二局科技资助项目(2021ZX140001-03);广东省基础与应用基础研究基金(2020A1515110810,2023A1515012881)。

摘　　要：基于穗莞深城际轨道项目,采用离散单元法对基坑深层岩体爆破过程进行数值模拟,并对周围地面影响加以安全性分析。首先,验证了PFC模拟爆破的合理性;随后通过单轴压缩试验,得到了合理的地质细观参数;并建立二维基坑模型,从不同初始应力、不同埋深以及是否存在预裂缝三个角度对地面扰动的影响进行了研究。结果表明:初始应力越大,对应的地面速度也越大;地面速度随炸药埋深的变化曲线呈上抛物线形状;预裂缝的存在可以有效减缓地面峰值速度,可达13%。Based on the Guangzhou-Dongguan-Shenzhen Intercity Railway Project,we use the discrete element method to simulate the blasting process of deep rock masses in foundation pits,and analyzes the safety of the surrounding environment.Firstly,the rationality of PFC simulation blasting was verified.Subsequently,reasonable geological microscopic parameters were obtained through uniaxial compression tests;and a two-dimensional foundation pit model was established to study the impact of ground disturbance from three perspectives,referring to different initial stresses,burial depths and the presence of cracks.The results indicate that:the greater the initial stress,the greater the corresponding ground velocity;the variation curve of ground velocity with the burial depth of explosives shows an upward parabolic shape;the presence of cracks can effectively reduce the peak ground velocity by 13%.

关 键 词：基坑爆破 PFC 爆破应力波 速度监测 预裂缝 

分 类 号：O382.2[理学—流体力学]