地下管道爆破振动安全允许峰值振速试验研究

Experimental Investigation on allowed Blasting Vibration Velocity of Underground Pipeline

为探究地下管道的安全允许峰值振速,通过现场试验对管道地表的爆破振动峰值振速、主振频率、及管道表面轴向微应变进行监测记录。分别对不同主频范围的峰值振速和管道轴向应变进行拟合分析,发现主频≤35 Hz和主频>35 Hz的拟合结果不同,且应变随峰值振速的增加呈指数增长。以管道的最大容许轴向应变峰值为管道的破坏判据,得到其安全允许峰值振速分别为14.44 cm/s(主频≤35 Hz)、17.21 cm/s(主频>35 Hz)。由此可见,应根据不同主振频率确定地下管道的爆破振动安全允许峰值振速,通过现场监测、管道情况制定和优化爆破施工方案。

In order to study the allowable peak particle velocity of buried pipelines,the blasting vibration and axial micro-strains were monitored by field test.By fitting the peak particle velocity of blasting vibration and axial strain of the pipeline according to main vibration frequency respectively,it was found that the fitting results were separated by the 35 Hz frequency point.And the strain grows exponentially with the velocity′s value.Taking the maximum allowable axial strain peak value of the pipeline as the failure criterion,the allowable peak vibration velocity of the pipeline was obtained to be 14.44 cm/s(main frequency≤35 Hz) and 17.21 cm/s(main frequency >35 Hz),respectively.It can be seen from this that the allowable peak vibration velocity of underground pipeline should be determined according to different main vibration frequencies,and the blasting construction scheme should be formulated and optimized through on-site monitoring and pipeline conditions.