EXPERIMENTAL STUDY ON DYNAMIC BEHAVIOR FOR BLASTING EXCAVATION OF LARGER-SPAN SHALLOW TUNNEL
In the course of tunnel construction by drilling and blasting method it is very important to study dynamic behavior induced by blasting. Aimed at investigating the vibration effect by blasting during the excavation of Miaoya diverging tunnel, this paper studies the vibration characteristic of the ground at the larger-span shallow part and the blasting vibration reduction technology for larger-span excavation. According to the regression analysis for the monitored results of blasting-induced vibration, the mathematical model for vertical propagation of blasting-induced vibration has been revised. Some conclusions are drawn on the basis of the analysis of the vibration characteristic of the ground and the tunnel: i.e. ⅰ) the dominating vibration frequency at surface mass point is mainly low frequency; ⅱ) the decreasing tendency of dominating vibration frequency at surface mass point is not obvious when distance increases; ⅲ) the high frequency is mostly absorbed by the concrete of the tunnel lining, so that the blasting vibration impacting on the rock becomes weaker; ⅳ) the ground blasting vibration velocity of the excavation region is higher than that of the rock region; and ⅴ) the ground blasting vibration velocity at the top of excavation region should be less than that of blasting security control in the larger-span shallow tunnel.
QING-SONG ZHANG YANG GAO SHU-CAI LI ZHEN-HAO XU
Geotechnical & Structural Engineering Research Center of Shandong University Jinan ,250061, China
国际会议
The 7th International Symposium on Rockburst and Seismicity in Mines(2009年第七届国际岩爆与微振动性学术研讨会)
大连
英文
575-580
2009-08-21（万方平台首次上网日期，不代表论文的发表时间）