中南大学学报（自然科学版）2016，Vol.47Issue(11)：3808-3817,10.DOI:10.11817/j.issn.1672-7207.2016.11.026
大型地下洞室开挖爆破破坏影响范围
Rock blasting-induced damage zone under blasting excavation in a large underground chamber
摘要
Abstract
The rock mass integrity was usually considered to have great influence on blasting excavation in a large underground chamber. Taking the short-hole blasting as research background for bench excavation of the main underground workshop with super-large section in Xiluodu hydroelectric power plant, located in the Jinsha River,at the junction of Sichuan and Yunnan in China, a model of rock blasting-induced damage taking initial damage into account was presented based on damage mechanics. The criterion for blasting-induced damage, which was related to the initial damage of rock, was also presented for determining the blasting-induced damage zone. The formula about the relation between the initial damage of rock and the integrity index of rock mass was proposed so that the presented model could consider the integrity of rock mass. The presented model was imported into the software FLAC3D by programming the numerical simulation for rock mass integrityion of blasting. Firstly, The analysis of the characteristics of rock blasting-induced damage zone of surrounding rock were made. Secondly, the maximum radius of blasting-induced damage zone in the horizontal-radial direction was considered as the characteristic parameter for the blasting-induced damage zone. The relations among the maximum horizontal radius of blasting-induced damage zone, the initial damage of rock, the blasting charge amount per delay interval and the peak particle velocity of vibration were also analyzed. As a result, the limited velocity of vibration and the safety charge amount corresponding to the rock damage under different initial damage were obtained. In the end, the results from tests on site including blasting tests, testing of peak particle vibration velocity and velocity of acoustic wave propagation in a borehole, were put forward. The rationality of numerical simulation was verified by the result comparisons between the tests on site and the numerical simulation. The results show that, for the short-hole bench blasting, the blasting-induced damage zone decreases with increment of blasthole depth in the horizontal-radial direction, and it expands to the maximum on the top free face of blasthole. The peak vibration velocity of particle located in the edge of blasting-induced damage on the top free face of blasthole can be used as the safety criterion for evaluating rock blasting-induced damage in the excavation monitoring process. The initial damage value of rock has remarkable influence on the maximum blasting-induced damage radius when the value is big. The results obtained from numerical simulation are in good agreement with those from tests on site.关键词
岩石力学/水电站地下厂房/爆破安全判据/爆破数值模拟/质点峰值振动速度/岩体完整程度Key words
rock mechanics/underground workshop of hydroelectric power plant/criterion for blasting safety/numerical simulation of blasting/peak particle vibration velocity/integity of rock mass分类
矿业与冶金引用本文复制引用
陈俊桦,张家生,李新平..大型地下洞室开挖爆破破坏影响范围[J].中南大学学报（自然科学版）,2016,47(11):3808-3817,10.基金项目
国家自然科学基金资助项目(51274157，51378514)(Projects(51274157,51378514) supported by the National Natural Science Foundation of China) （51274157，51378514）
