冰介质爆破特性实验研究

迄今 ,由于缺乏对冰介质爆破特性的了解 ,黄河防凌爆破仍停留在局部经验阶段。本文对冰介质的力学特性进行了实验研究 ,并测定了部分力学特性。结果表明 ,在爆炸载荷作用下 ,冰介质呈现明显的脆性变形 ,并且其抗压强度是抗拉强度的 3～ 6倍。通过 -2 5℃气温条件下冰介质中标准爆破漏斗试验 ,求得炸药单耗为 83 0 g/m3,与爆破中软岩石的炸药单耗相当。

NUMERICAL SIMULATION RESEARCH ON VIBRATION SUPERPOSITION EFFECTS IN THE MILLISECOND DELAY BLASTING

First of all,the single-hole blasting seismic wave was analyzed by numerical simulation method, the change law of its wave shape corresponded with the relative researches.Based on the single-hole blasting vibration analysis,milliseccnd blasting vibration wave-shape superposition effects were simulated with delay time intervals between 0 and 25 milliseconds,the feasibility and practicality of two different delay time interval theory were discussed.The results showed that vibration velocity caused by millisecond delay blasting was lower than that caused by simultaneous blasting,even though the delay time interval was less than 1/5 of main quake period,vibration velocities of partial measuring points caused by millisecond delay blasting were lower than those caused by single-hole blasting when the delay time interval was nearby 1/2 of main quake period,the reliability of decreasing vibration was not high because of the irregular vibration period;and the superposition of main quake segments was avoided when the delay time interval was longer than the duration of seismic wave so as to make vibration velocity caused by holes millisecond delay blasting reduce to the vibration velocity caused by the single-hole blasting.