两河口水电站级配料开采爆破孔间延时优选的试验研究  

Experimental Study on Delay Optimization between Blasting Holes in Grade Batching Mining of Lianghekou Hydropower Station

作　　者：余良松 周龙杰 胡英国[2] 胡伟[2] YU Liang-song;ZHOU Long-jie;HU Ying-guo;HU Wei(Sinohydro Twelfth Engineering Bureau Co.,Ltd.,Hangzhou 310004,China;Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of Water Resources,Yangtze River Science Research Institute,Wuhan 430010,China)

机构地区：[1]中国水利水电第十二工程局有限公司,杭州310004 [2]长江水利委员会长江科学院水利部岩土力学与工程重点实验室,武汉430010

出　　处：《爆破》2021年第4期81-88,共8页Blasting

基　　金：国家自然科学基金资助项目(52079009);中央科研业务费项目(CKSF2019477/YT)。

摘　　要：水电工程领域,开采的堆石坝级配料合格与否直接关系到大坝的填筑质量和坝体运行期的安全,需引起足够重视。以两河口水电站堆石坝开采为工程背景,开展了精确毫秒延时条件下孔间延迟时间对爆破级配影响的试验研究。首先从理论角度阐述了孔间延时对爆破块度影响的力学原理,进而结合料场开采设计了12种试验工况开展对比研究,从级配分布、不同粒径区间以及平均块度等多方面分析了孔间延迟时间对爆破块度影响特性,试验结果表明:不同的孔间延迟时间对爆破级配的影响明显,且孔间延迟时间对粒径的影响具有明显的分区特性,对于10 mm以下粒径,延迟时间的影响并不明显,对于10~80 mm粒径的块度,其分布变化具有明显的波动特征和周期性规律,与不同延迟时间下的应力波叠加密切相关,对于80 mm以上的粒径块度,孔间延时的影响逐渐减小,岩体的天然结构面切割起主要作用。孔间延迟时间对平均块度的影响明显,随着延迟时间的增加,平均块度先减小后增大,在10 ms时取得最小值,表明此时的破碎效果最好,但从水工级配料包络线的级配最优角度,通过比较与包络线中线的误差率,孔间延迟时间为20 ms时最优,印证了水工堆石坝级配料开采与矿山开采存在区别,破碎程度不是唯一指标,应当是通过合理的设置孔间延时,使炸药能量合理的破碎岩石并形成特定的不均匀级配。In the field of hydropower engineering,whether the grade of rockfill dam ingredients is qualified or not is directly related to the filling quality of the dam and the safety of the dam body during operation period,which should be paid enough attention to.Taking the mining of rockfill dam of Lianghekou Hydropower Station as the engineering background,this paper carried out the experimental research on the influence of delay time between holes on blasting grading under the condition of precise millisecond delay.Firstly,the mechanical principle of the influence of delay time between holes on blasting fragmentation is expounded theoretically.Then,12 kinds of test conditions are designed to carry out comparative study combining with the mining field.The influence characteristics of delay time between holes on blasting fragmentation are analyzed from grading distribution,different particle size range and average fragmentation.The effect of delay time between holes on blasting gradation is obvious,and the effect of delay time between holes on particle size has obvious zoning characteristic.For the particle size which is less than 10 mm,the effect of delay time is not obvious.But for the particle size of 10~80 mm,the distribution change has obvious wave characteristic and periodic rule,which is closely related to the superposition of stress waves under different delay time.For the particle size which is above 80 mm,the effect of time delay between holes gradually decreases,and the cutting of natural structural plane is the main role.Meanwhile,the effect of delay time between holes on average fragmentation is obvious.With the increase of delay time,the average fragmentation first decreases and then increases,and the minimum value is obtained at 10 ms,which indicates that the crushing effect is the best at this time.However,from the perspective of optimal gradation of hydraulic grade proportioning envelope,by comparing the error rate with the centerline of envelope,it is the best when the delay time between holes is 20 ms,

关 键 词：爆破 延迟时间 应力波 级配 优化 

分 类 号：TU746.6[建筑科学—建筑技术科学]