【作者】 田华；

【导师】 舒继森；

【作者基本信息】 中国矿业大学 ， 露天开采， 2019， 博士

【摘要】 新疆是“一带一路”建设沿线的重要节点,在能源保障和技术输出方面一直担负着重要的任务。准东煤田作为新疆的第三大煤田,有40%的储量适合采用露天开采。准东煤田的多座露天矿目前已接近转向阶段,一系列的相似的工程和安全问题在这一区域集中涌现,针对准东露天矿生产过程中的典型安全技术问题进行研究,其成果将在整个准东煤田具有良好的推广性。采用地质调查和数据分析等手段,查明了的影响准东露天矿边坡稳定的三类主要因素;确定了的地质构造属简单型、岩体为易崩解软岩;阐明了采场边坡的失稳模式以顺层滑坡为主,排土场边坡以圆弧滑坡为主,复合边坡以圆弧-顺层滑坡为主。根据构造应力图解方法确定准东矿区的水平主应力方向为N21°E,该应力对边坡稳定性影响较小。从理论上分析了振动液化形成的原因以及液化后的物理力学特征,结合准东露天矿的振动源类型,设计不同工况的振动条件探索砂土边坡的动力稳定性。试验测定不同振动加速度和振动频率条件下砂土边坡的超静孔隙水压力和超孔压比的时程变化规律,结果表明:振动加速度或振动频率越大,砂土边坡峰值超静孔隙水压力越高,并且达到峰值的时间越短。建立了倾斜基底上排土场堆载形成的边坡几何结构、力学模型,揭示了排土场边坡稳定性随着高度的增长呈二次函数规律递减。综合排土场倾斜基底稳定性、边坡稳定性和最大边坡角这三个因素,构建了内、外排土场稳定性线性规划模型,提供了确定边坡最大安全角度的方法。建立了非对称排土场三维受力模型,引入排土场两侧基底的支撑力,修正了非对称基底软岩排土场的稳定性计算方法。根据自重应力和侧压计算方法,推导出了陡帮开采过程中,端帮岩体有效抗剪强度和正应力的计算公式,揭示了有效抗剪强度随边坡角度增大呈余切函数规律递减,正应力与端帮边坡角呈负相关。建立倾斜条件下非对称弱层挤压模型,确定了临空侧弱层挤出时上覆堆载体需要满足的最小厚度。针对准东露天矿顺倾基底弱层的特征,提出了弱层挤出控制方法。建立排土场凹形边坡力学模型,基于极限平衡原理和条分法推导出了凹形排土场边坡稳定系数计算方法。采用模拟分析确定准东露天矿平直和凹形排土台阶的最大安全高度分别为64m和80m。内排跟进压帮之后首采区西帮靠帮开采的最佳角度为38°。通过分析准东露天矿当前面临的剥离物下行运输的问题,论证了倾斜端帮下行运输与排土场下行运输的技术经济性,提出了端帮道路优化解决重车下行方案,取消▽430水平端帮路,设置▽414水平西端帮路,内排土场台阶并段形成▽414水平台阶及新▽462水平台阶,提供了后续生产过程中端帮并段及排土场升段工程实施方案。该论文有图75幅,表9个,参考文献124篇。更多还原

【Abstract】 Xinjiang is the pivot of the “Belt and Road” construction line and has always played an important role in energy security and technology output.As the third largest coal field in Xinjiang,Zhundong Coalfield has 40% of its reserves suitable for open pit mining.Many open pit mines in Zhundong Coalfield are now approaching the turning phase.A series of similar engineering and safety issues have emerged in this area.The research on the typical safety technology issues in the production process of the Zhundong Opencast Mine has been carried out,which results has a good promotion in Zhundong Coalfield.The geological survey and data analysis were used to determine the three main factors affecting the stability of the Zhundong open pit mine slope.It identified the geological structure is simple,and the rock mass belongs to easily disintegrated soft rock.The loss of the stop slope is clarified as the slope of stope slope is dominated by bedding landslides,the slope of the dumping site is dominated by circular landslides,and the composite slope is dominated by arc-bed landslides.According to the tectonic stress graphic method,the horizontal principal stress direction of the Zhundong mining area is determined to be N21°E,which has little effect on the slope stability.The causes of vibration liquefaction formation and the physical and mechanical characteristics after liquefaction are theoretically analyzed.The vibration conditions of the Zhundong open-pit mine are combined with the vibration conditions of different working conditions to explore the dynamic stability of the sand slope.The time-dependent changes of the ultra-hydrostatic pore water pressure and the excess pore pressure ratio of the sand slope under different vibration acceleration and vibration frequency are tested.The results show that the vibration acceleration or vibration frequency is larger,the ultra-hydrostatic pore water is higher,and the shorter the time to peak.The geometry and mechanical model of the slope formed by the dumping on the inclined base are established,which reveals that the slope stability of the dump slope decreases with the increase of the height.Based on the three factors of stability of slope foundation,slope stability and maximum slope angle,a linear programming model of internal and external dumping stability is constructed,which provides a method to determine the maximum safety angle of the slope.A three-dimensional force model of asymmetric dumping field is established,and the supporting force of the basement on both sides of the dumping field is introduced,and the stability calculation method of the asymmetric soft rock dumping site is modified.According to the calculation method of gravity stress and lateral pressure,the calculation formulas of effective shear strength and normal stress of the end rock mass during the steep mining process are derived,which reveals that the effective shear strength decreases with the increase of the slope angle.The normal stress is negatively correlated with the angle of the end slope.The asymmetric weak layer extrusion model under the inclined condition is established,and the minimum thickness that needs to be satisfied by the overlying carrier during the extrusion of the weak side layer is determined.Aiming at the characteristics of the weak base weak layer in the Zhundong Open-pit Mine,a weak layer extrusion control method is proposed.The mechanical model of the concave slope of the dumping site is established.Based on the limit equilibrium principle and the strip method,the calculation method of the slope stability coefficient of the concave dump is derived.The maximum safe heights of bench for the straight and concave inner dump of-Zhundong Open pit mine were determined by simulation analysis to be 64 m and 80 m respectively.As the inner dump rapid follow to the mining bench,the optimum angle for western slope in the first mining area is 38°.By analyzing the problem of the downward transportation of the stripping material currently faced by the Zhundong Open-pit Mine,the technical and economical characteristics of the downward transport of the inclined end and the downstream transport of the dumping site are demonstrated,and the end-help road is optimized to solve the heavy-duty vehicle down-plan and the ▽430 level is cancelled.The end of the road,set the ▽414 horizontal end of the road,the internal dumping step and the formation of the ▽414 horizontal step and the new ▽462 horizontal step,providing a follow-up production process in the end of the section and the dumping section of the project implementation plan.This dissertation includes 75 figures,9 tables,and 124 pieces of reference.更多还原