石灰石矿山台阶边坡爆破振速安全阈值研究

爆破是矿山露采的必要手段,爆破振速安全阈值的确定对矿山台阶边坡的安全开采起着重要的作用。以四川兴联石灰石矿山台阶边坡为例,采用速度判别法,选取规范中的爆破振速安全阈值为拟静力法和动力显示分析法作参考;采用拟静力法,选取优势结构面作为潜在滑动面反演得到爆破振速安全阈值;采用ANSYS/LS-DYNA的动力显示分析法,建立台阶边坡模型,选取模拟监测点数据与实际监测数据进行对比,并结合质点振动速度与应力进行回归分析得到爆破振速安全阈值。通过对三种方法的对比研究得到,拟静力法与动力显示分析法得到的结果接近,且符合速度判别法中的规范。综合三种分析方法最终对台阶边坡爆破振速安全阈值进行合理取值。

Study on the safety threshold of blasting vibration velocity of bench slope

Blasting is a necessary means of mine mining, making the determination of safety threshold of blasting vibration velocity of vital importance to the mining safety of bench slope. Focused on the bench slope in the Xing lian limestone mine, safety threshold of blasting vibration velocity in relative standards was selected as benchmark value to the quasi-static method and dynamic display analysis method. With the application of quasi-static method, safety threshold of blasting vibration velocity was obtained via back analysis with the predominant discontinuities as the potential sliding surface; dynamic display analysis method in ANSYS/LS-DYNA was applied to build up bench slope model, furthermore, the monitoring data in the model was compared with the field monitoring data and the safety threshold of blasting vibration velocity was gained through the regression analysis of vibration velocity and stress of model point. The comparative study of the three methods indicates that the results of quasi-static method is close to that of the dynamic display analysis method, and both of the methods conform to the norms in the speed discrimination method. The safety threshold of blasting vibration velocity was selected based on the comprehensive analysis of the three mentioned method.