基于高速摄影法对孔桩内导爆管准爆的探究

摘要

针对贵阳花果园V区孔桩爆破中塑料导爆管多次产生拒爆的实际情况，为降低盲炮的产生、提高准爆率，特对导爆管传爆性能进行研究。首先，利用高速摄像机进行完整导爆管的传爆试验，获得所使用导爆管的稳定爆速为1650 m/s；然后进行切缝试验，得出切缝长度在12 cm以上导爆管将产生断爆，断爆爆速临界值为525 m/s；最后进行注水试验，当注水长度达2 mm必断爆。结果表明：施工误操作破损后的塑料导爆管使用在含水的孔桩内，盲炮率较高，切缝是导致拒爆的诱导因素，注水是主导因素；施工过程中应采取有效措施减少孔内积水及确保导爆管完整无缝隙，防止积水渗入导爆管导致拒爆，可有效降低盲炮率。%The Nonel tube misfired many times in the pile blasting at V area Hua Guoyuan in Guiyang city. In order to reduce misfire and to improve the firing reliability,the Nonel tube performance of explosion transference was studied. Firstly,the stable prorogation velocity of None with 1650 m/s was measured by high-speed photography . Then the cutting seam test of tube was performed,and when the cutting seam length was more than 12 cm,misfire happened in detonating tube. Furthermore,the critical velocity causing misfire was 525 m/s. Finally,water injection into tube more than 2 mm would induce misfire. When the Nonel tube was damaged by wrong operation in construc-tion in the pile with water,the misfire rate was higher,where the cutting seam was induced factors and water the dom-inant factor. In the process of construction,all the measures such as reducing the water and ensuring the tube integrity could effectively reduce the misfire rate.