基于HHT分析的浅埋隧道爆破振动控制研究

以青岛地铁施工过程中浅埋段隧道下穿建筑物为例,运用HHT分析理论结合MATLAB软件研究了爆破振动监测信号的时频关系,分析雷管的起爆时间间隔,为振动控制提供理论依据。通过分析发现:1)爆破振动信号的频率基本在90 Hz以下,优势频率范围为20~70 Hz;2)根据《爆破安全规程》规定的安全允许标准,3号民房爆破安全允许振速可定为2.0 cm/s,设计振速1.0cm/s较为保守;3)不考虑雷管自身延时误差的情况下,60 ms将是雷管比较理想的段与段之间延期时间间隔;4)实际爆破过程中,雷管延时误差是普遍存在的,总体误差呈现为正值。

Study on Blasting Vibration Control of Shallow Tunnel Based on HHT Analysis

The relationship between the time and frequency of blasting vibration monitoring signal monitored from the construction of a shallow tunnel in Qingdao crossing underneath buildings is studied by means of HHT analysis theory and MATLAB programming software, and the interval between the ignitions of the detonators is analyzed, so as to provide theoretical reference for vibration control. Conclusions drawn are as follows: 1) The frequency of the blasting vibration signals is basically below 90 Hz, and the dominant frequency range is from 20 Hz to 70 Hz; 2) The allowable safe vibration velocity of No. 3 building can be designed at 2.0 cm/s according to the blasting safety regulations. The designed safe vibration velocity value, i.e., 1.0 cm/s, is relatively conservative; 3) 60 ms will be the ideal time interval between detonators, without considering the delay errors of the detonators; 4) Delay errors of detonators generally exist in blasting, and generally the error is a positive value. 