某露天石英矿台阶型边坡爆破三维模拟及其动态响应研究

Three−Dimensional Numerical Simulation and Dynamic Response Analysis of Blasting−Induced Effects on Benched Rock Slopes in an Open−Pit Quartz Mine

  • 摘要: 针对传统边坡爆破动力响应分析中,二维平面模型及间接震动荷载难以真实反映三维应力波传播与爆炸能量持续做功的局限性,以某石英矿爆破开采为工程背景,结合三维精细地质建模、炸药Jones−Wilkins−Lee(JWL)状态方程与Johnson−Holmquist Ⅱ(JH−2)岩体损伤本构模型,提出了一种贴合工程实际的三维全过程直接模拟方法。该方法实现了从爆炸能量释放到边坡动力响应的完整模拟,直观再现了爆破应力波与台阶结构及自由面的空间相互作用。模拟结果表明,边坡在爆破作用下呈现出显著的高程放大效应,平台动态响应随高程增加而更为剧烈;以靠近爆源且拟合度最高的 2# 监测线为例,在爆破全过程中,其峰值位移由 0.83 mm 激增至 18.79 mm。同时,与现场监测数据的系统对比证实,该方法的计算误差远低于传统二维剖面模型,其三维绝对误差(mean absolute error,MAE 介于 0.20~5.66 mm)整体显著小于二维模型(0.92~7.56 mm)。本研究有效克服了传统数值模拟中荷载简化与维度缺失的问题,为复杂台阶地形条件下的爆破动态响应分析与稳定性评价提供了一种高精度的新范式。

     

    Abstract: Conventional approaches for analyzing slope dynamic responses to blasting often rely on two−dimensional planar models and indirect vibration loading, which fail to realistically capture the three−dimensional propagation of stress waves and the continuous energy exertion generated by the explosion. To address these fundamental limitations, this study proposed a three−dimensional full−process direct simulation method closely aligned with engineering practice, based on the blasting operation of a quartz mine. The method integrated three−dimensional refined geological modeling, the Jones−Wilkins−Lee (JWL) equation of state for explosives, and the Johnson−Holmquist Ⅱ (JH−2) constitutive model for rock mass damage. This integrated approach enabled a complete simulation spanning from the initial release of explosive energy to the subsequent dynamic responses of the slope, and intuitively reproduced the intricate spatial interactions among blasting stress waves, bench structures, and free surfaces. The simulation results reveal significant elevation amplification effects on the slope under blasting. Dynamic platform responses intensify progressively with increasing elevation. Taking the 2# monitoring line, which is located closest to the blast source and exhibits the highest fitting accuracy, as a representative example, the peak displacement increases dramatically from 0.83 mm to 18.79 mm as elevation increases. Systematic comparisons with field monitoring data further demonstrate that the computational errors of this proposed method are substantially lower than those of traditional two−dimensional profile models. Specifically, the three−dimensional model achieves a Mean Absolute Error (MAE) ranging from 0.20 to 5.66 mm across different monitoring points, which is significantly smaller than the MAE range of 0.92 to 7.56 mm observed for the two−dimensional model. The superior accuracy of the three−dimensional approach confirms that full consideration of spatial stress wave propagation and continuous energy input is essential for reliable dynamic response predictions. This study effectively overcomes the long−standing issues of load simplification and dimensional deficiency inherent in conventional numerical simulations, and provides a high−precision paradigm for dynamic response analysis and stability evaluation of slopes under complex bench terrain conditions.

     

/

返回文章
返回