城市小间距交通隧道爆破安全监测及结果分析

Blast monitoring and analyses for urban traffic tunnels with small spacing

根据长沙市小间距交通隧道的爆破安全现场监测结果,进行了安全性评价及地震波衰减规律分析。安全性评价分别采用振速峰值和振速-频率安全判据进行评判,结果表明各测试结构物在测试爆破条件下是安全的,且具有较大的安全空间,可适当增加装药量,以加快施工速度,节约资金。通过萨道夫斯基经验公式回归分析,给出了测试条件下的场地系数K和地震波衰减指数α的值,并由此反演得到任意质点振速峰值预测公式和最大(段)允许装药量的控制公式,且后续施工证明装药量控制值是可靠、安全的。

Based on the data obtained in the blast monitoring of urban traffic tunnels with small spacing in Changsha city, safety evaluation and analyses of the law of blasting vibration attenuation were carried out. Particle peak vibration velocity （ PPVV ） and vibration velocity -frequency criteria were used for safety evaluation. Results indicated that structures were safe under the test blast conditions and it was feasible to increase explosive quantity to fasten construction and save investment. According to Sadaovsky empiric formula, regression analyses were performed with the values of K andαobtained, then the prediction formulas of PPVV for predicting the PPVV at any point were established. In addition, the control formula of explosive quantity for estimating the maximum explosive quantity in construction was put forward and justified to be safe and reliable in the following tunnel projects.