多因素耦合影响下隧道电子雷管爆破参数的计算与实践

基于电子雷管起爆的参数计算方法是爆破控制精准化和智能化的基础,其研究尚处于起步阶段。以重庆观音桥隧道为研究背景,提出了精确确定电子雷管爆破参数的多因素耦合法,其特点是基于多个爆破参数间复杂的耦合关系进行爆破参数设计。研究表明:不同药量的最优微差时间不同,爆破孔数对最优微差时间及对应最大合成振速有显著影响;采用该方法确定的试验隧道最优爆破参数为8孔逐孔掏槽、1.4 kg单孔药量、5 ms孔间延时。现场设计孔间延时为5 ms和8 ms的两组掏槽爆破试验,分析了两种孔间延时掏槽爆破的第二临空面形成时间。试验结果表明:对于短延时掏槽爆破而言,即使未形成第二临空面,采用多因素耦合法,通过最大程度的波形异向相消,也可以实现较好的降振效果。对比多因素耦合法与半周期错相减振法,后者计算的孔间延时不能确保是最优微差时间,可能造成合成振速偏大。当需要严格控制爆破振动时,通过多因素耦合法可以实现爆破参数的精确设计。

Calculation and practice of blasting parameters of electronic detonator in tunnel under the influence of multi-factor coupling

Parametric calculation method based on electronic detonator is the basis of precision and intelligence of blast control,and its study is still at the starting stage.Here,taking Chongqing Guanyin Bridge tunnel as the study background,the multi-factor coupling method to accurately determine blast parameters of electronic detonator was proposed with the feature to design blast parameters based on their complex coupled relations.The study showed that the optimal delay values of different charges are different,the number of blast-holes has a significant influence on the optimal delay and the maximum synthetic vibration velocity;the optimal blast parameters of the tested tunnel determined with the proposed method are 8 holes with hole-by-hole cutting,1.4 kg single hole charge,and 5 ms inter-hole delay.Two groups of cutting blast tests with delays of 5 ms and 8 ms were designed on-site,and the formation time of the second free surface for two delays cutting blast inter-hole was analyzed.The test results showed that for short delay cutting blast,even if the second free surface is not formed,the multi-factor coupling method can realize better vibration reduction effect through the maximum degree of waveform opposite direction cancellation;the multi-factor coupling method is compared with the half-period phase staggering vibration reduction method,the delay inter-hole calculated using the latter can’t be ensured to be the optimal delay,it may cause a larger synthetic vibration velocity;when the blast vibration needs to be controlled strictly,the multi-factor coupling method can realize the precise design of blast parameters.