Abstract:

In order to study the blasting vibration rules of lining structure of Jiaohuayu Tunnel on Xingyan Expressway in Beijing during blasting construction of top heading,the blasting vibration velocity of the tunnel lining during advancing of tunneling face is monitored by setting a sensor on crown top, hance and sidewall respectively 38 m behind tunneling face. Three components of blasting vibration velocity are analyzed by Sodev's nonlinear regression analysis method. Some conclusions are drawn as follows: 1) The vibration velocity of crown top is the largest, followed by that of hance, and that of sidewall is the smallest. 2) The fitting parameters K and α of blasting vibratian velocity of crown top along vertical direction, horizontal radial direction and horizontal shear direction are larger than those of hance and sidewall; and the vibration velocity along vertical direction is the largest. The regression analysis is carried out on the basic vibration frequency in crown top, hance and sidewall; and the regression parameter K shows that the basic vibration frequencies in different positions show a relationship of fcrown top＞fsidewall＞fhance. The wavelet energy analysis shows that the frequency components in hance are relatively abundant and the bandwidth is wide; the low frequency component energy in hance and sidewall position is much higher than that in crowan top; and the low frequency energy in hance is the highest.

Key words: tunnel blasting, vibration rules, basic vibration frequency, wavelet analysis