炮孔壁初始冲击压力直接测量试验研究  

Experimental study on direct measurement of initial shock pressure on the hole wall

作　　者：李启月[1] 魏快快 马晶晶 田军 魏新傲 徐恒阳 肖宇航 LI Qi-yue;WEI Kuai-kuai;MA Jing-jing;TIAN Jun;WEI Xin-ao;XU Heng-yang;XIAO Yu-hang(School of Resources and Safety Engineering,Central South University,Changsha 410083,China;Tibet Zhongjin Xinlian Blasting Engineering Co.,Ltd.,Lhasa 850000,China)

机构地区：[1]中南大学资源与安全工程学院,长沙410083 [2]西藏中金新联爆破工程有限公司,拉萨850000

出　　处：《工程爆破》2024年第3期1-7,19,共8页Engineering Blasting

基　　金：新疆维吾尔自治区重大科技专项基金资助项目(2018A03003)。

摘　　要：基于电测法构建出一套测试系统对孔壁压力进行直接测量,以获得现场岩石炮孔中的孔壁压力实测数据,根据灵敏度、抗冲击和抗干扰能力等参数,选择PVDF压电传感器作为压力测试系统的敏感元件;根据爆炸荷载的加载特性,选择并联25Ω碳膜电阻的电流模式作为系统的测试电路;最后根据带宽、采样率等参数选择示波器进行数据采集。将测试系统应用于高速公路边坡爆破开挖中,试验得到炮孔壁轴向距炸药0、0.1、0.2、0.3 m 4个位置的压力时程曲线,结果表明:在90/32的装药条件下,轴向距炸药0~0.3 m范围内,孔壁峰值压力范围为1 446~156 MPa;各测点的压力上升时间为6.1~1.5μs,距离炸药越近、压力上升时间越长;对试验值进行拟合,发现在轴向距炸药0~0.3 m范围内孔壁压力峰值呈幂函数递减。试验验证了孔壁压力直接测试系统的可靠性。Based on the electrical measurement method,A test system is constructed to directly measure the hole wall pressure,so as to obtain the measured data of the hole wall pressure in the rock borehole in the field.According to the parameters of sensitivity,impact resistance and anti-interference ability,PVDF piezoelectric sensor is selected as the sensitive element of the pressure test system.According to the loading characteristics of explosion load,the parallel current mode of 25Ωcarbon film resistor is selected as the test circuit of the system.Finally,according to bandwidth,sampling rate and other parameters,Oscilloscope is selected for data acquisition.The test system was applied to the blasting excavation of highway slope,and the pressure time history curves of the four positions of 0 m,0.1 m,0.2 m and 0.3 m from the blasting explosive were obtained.The results show that under the condition of 90/32 charging,the peak pressure range of the blasting explosive is 1446~156 MPa in the range of 0~0.3 m from the axial distance.The pressure rise time of each measuring point is 6.1~1.50x0E䥺SymbolmA@0x0Fs,and the closer to the explosive,the longer the pressure rise time.By fitting the test values,it is found that the peak value of hole wall pressure decreases as a power function in the range of 0~0.3 m from the explosive.The reliability of the direct measurement system for hole wall pressure is verified by experiments.

关 键 词：轮廓爆破 孔壁压力 测试系统 PVDF压电薄膜传感器 现场试验 

分 类 号：TB41[一般工业技术]