线性装药爆破去除输电线覆冰研究

De-Icing Power Line by Linear Shaped Explosive Blast

针对输电线由于覆冰引起各类事故灾害的问题,采用线装药爆破方式进行除冰是一种新思路。为研究该方法的除冰机理和关键技术,通过小尺寸覆冰输电线的爆破实验和数值模拟,研究爆破除冰机理和爆破参数影响规律。结果表明:爆炸载荷的直接作用使迎爆面覆冰大量粉碎,背部覆冰内形成贯穿型裂纹,随后解体或者在电线的冲击振动下脱除。当覆冰对导爆索约束较弱时,爆炸能量从约束较弱侧迅速衰减,当覆冰无法形成贯穿型裂纹时则不能脱冰。导爆索位于覆冰内部时有利于爆破除冰,因此应根据覆冰厚度预估装药间隔。

To control the risk of disaster that may be caused by ice-coated power line, a novel de-icing method by applying linear shaped explosive blast has been proposed in the past decade. To investigate the mechanism and the key technology, blast tests on short ice-coated power line are performed as well as corresponding LS-DYNA simulations. The effects of blast parameters on de-icing efficiency are also discussed. Results show that, ice on the blast side immediately crush while through-wall cracks appear in the other side ice which then fractures or falls from the line. The blast energy rapidly attenuates from the weakly constrained side of ice when the detonation cord is placed outside of the ice. As a consequence, in order to de-ice with high efficiency, the gap between conductor and detonation cord should be optimized according to estimation ice coating thickness to ensure that the detonation cord is located within the ice coating.