爆破振动对地下管道影响试验及风险预测

摘要

To explore the influence of blasting vibration on underground pipelines,the peak particle velocity was used as a criterion of blasting vibration and the strain was used as a criterion of underground pipeline affected by vibration.A TC-4850N blasting vibration measurer and a DH3820 static strain test system were used to monitor the blasting construction of a project.They measured surface vibration signal and the axial and circumferential strain of the pipe.Fitting analysis of peak particle velocity and pipeline strain shows that there is exponential relationship between blasting vibration peak.particle velocity and axial and circumferential strain of corresponding underground pipelines.The fitting relationship was combined with the attenuation law of blasting vibration to predict the maximum ground peak velocity that the pipeline can support.The safe distance was 25.25 m.Thus it needs to improve the 50 m prohibiting range in blasting and forecast the safe distance of underground pipeline according to the actual situation.%为了降低爆破振动有害效应,探究爆破振动对地下管道的影响,需基于管道破坏的应变准则,建立爆破振动质点峰值速度与管道破坏的对应关系.利用TC-4850N爆破振动测试仪、DH3820静态应变测试系统在大龙经济开发区高铁城棚户区山地场平工程进行爆破现场试验;对获得不同爆心距、不同最大段装药量时管道地表振动峰值速度及相应管道轴向、环向应变,进行拟合分析,结果表明合成峰值振速与地下管道轴向、环向应变呈指数函数关系;结合该场地条件下爆破振动衰减规律及管道最大容许应变,预测出试验条件下管道所能承受的地表最大峰值振速及此爆破条件下管道爆破施工安全距离.分析表明,燃气管道50 m范围内禁止爆破施工的规定有待改进,应根据实际情况分析预测地下管道安全距离.