复杂环境下跨路桥梁拆除爆破方案优化研究  

Optimization of Blasting Schemes for Demolition of Cross-road Bridges in Complicated Conditions

作　　者：齐鹏 尚修瑞 刘川 张建华[1] 姜婷婷[1] QI Peng;SHANG Xiu-rui;LIU Chuan;ZHANG Jian-hua;JIANG Ting-ting(School of Resources and Environmental Engineering,Wuhan University of Technology,Wuhan 430070,China;China Railway 14th Bureau Group 4th Engineering Co.,Ltd.,Jinan 250002,China)

机构地区：[1]武汉理工大学资源与环境工程学院,武汉430070 [2]中铁十四局集团第四工程有限公司,济南250002

出　　处：《爆破》2021年第3期104-112,共9页Blasting

基　　金：青年自然科学基金(51804263)。

摘　　要：福建省大井垄大桥因道路改造需爆破拆除,该桥梁为钢筋混凝结构,长187 m,宽24 m,中间有5排墩柱,共6跨,跨径30 m,周围环境复杂,桥梁底面距离桥下马路最高达到29 m,需严格控制爆破飞石、爆破振动、触地振动等危害。通过理论分析并运用ANSYS/LS-DYNA数值模拟软件对对称起爆、单向起爆和中间起爆三个预选方案进行模拟,通过对比爆堆范围和触地振动大小,发现中间起爆方式效果最好。通过对比不同排间延期时间的模拟结果,对原设计的短延期爆破方案进行优化,最终采用中间起爆长延期的爆破方案。同时采用预铺缓冲层、多层缠绕防护和砂土堤防护等措施来控制爆破危害。现场爆破结果表明:采用优化方案和振动控制措施后取得了良好的爆破效果,大桥实际爆堆形态与模拟结果大致吻合,各监测点的峰值振动速度与模拟结果较为接近,对周围重要设施的影响均符合要求。The Dajinglong bridge in Fujian province needs to be demolished by blasting due to road reconstruction,which is a reinforced concrete structure with length of 187 m and width of 24 m.There are 5 rows of piers and 6 spans,and span length is 30 m.The surrounding conditions are complicated.The maximum vertical distance between the bridge and the road under the bridge is 29 m.It is necessary to accurately control the hazards such as blasting flying rock,blasting vibration,and touch ground vibration.Through theoretical analysis and numerical simulation with ANSYS/LS-DYNA to simulate three pre-selected schemes,symmetrical initiation,one-way initiation and intermediate initiation.Comparing the blasting pile and the magnitude of the touch ground vibration,it is found that the intermediate initiation method is the best scheme.By comparing the simulation results of the delay time between different rows,the original design of the short-delay blasting scheme was optimized,and finally the blasting scheme with intermediate initiation and long-delay time was adopted.At the same time,measures such as pre-paved buffer layer,multi-layer winding protection and sand embankment protection are adopted to control blasting hazards.The on-site blasting outcomes show that good blasting results have been achieved after adopting the optimized scheme and vibration control measures.The actual blast pile shape of the bridge is roughly consistent with the simulation results.The peak vibration velocity of each monitoring point is relatively close to the simulation results,and meets the requirements of the surrounding important facilities.

关 键 词：桥梁 拆除爆破 数值模拟 触地振动 控制措施 

分 类 号：TD746.5[矿业工程—矿井通风与安全]