【作者】 任月龙；

【导师】 才庆祥；

【作者基本信息】 中国矿业大学 ， 采矿工程， 2014， 博士

【摘要】 论文对露天煤矿软岩复合边坡形成机理及力学行为特性与开采控制技术进行研究，综合国内外研究现状，明确了露天采、排工程造成地应力及岩体位移对于露天矿安全生产的重要性。通过对中国露天矿地质条件的统计分析，建立了我国大型露天矿山的工程地质分类库，并根据地质条件对我国露天矿进行了区划分类，明确了对软弱岩质边坡反复开挖堆载过程应力-应变力学行为特性的研究目标，制定了合理的技术路线。基于开挖-堆载的基本工程步骤，推导了开采作业过程中开挖工程量的计算公式，并根据开挖方量推导出均匀排弃时排土场高度计算公式，结合胜利露天矿的基本参数及排土场的实际排弃方式，得出了该露天矿外排土场高度变化规律曲线。根据软岩的失稳模式及流变特性，确定了该类型边坡的失稳模式和计算方法，采用有限元分析原理结合数值模拟软件，计算软岩复合边坡稳定性，揭示了软岩复合边坡发展过程中稳定性变化规律。堆载作业造成了散体材料在重力压缩作用下重塑胶结，散体物料的密实度提高，抗剪强度随重塑压力增大呈线性关系递增、黏聚力呈二次线性增加。反复堆载作业造成完整软弱岩体长期处于剪切作用，完整岩体的力学参数随堆载压力及压缩时间的增长呈负指数规律递减。堆载作业对散体材料抗剪强度具有强化作用，对基底完整岩体具有弱化作用。软岩反复开挖-堆载过程产生促成岩体变形的动力源，开挖-堆载作业造成了边坡不平衡应力在临空面卸荷及基底区域的卸荷，造成坡脚应力集中及采场周围应力拱的形成。开挖-堆载产生的不平衡应力促进了软岩边坡变形发展。根据软岩的流变特性及位移计算公式，阐述了堆载作用下的位移计算公式，并借助数值模拟得到软岩堆积产生的主要位移，揭示了软岩开挖堆载应力-应变特性。胜利露天矿南帮边坡工程地质及水文条件进行了系统的分析，统计了弱层及硬岩的特征及分布情况，选择合适的岩性参数及典型的计算剖面，计算了南帮边坡的稳定系数，根据稳定性分析结果，设计了软岩边坡下南帮下部资源回收控制开采方案，较好的实现了软岩边坡条件下的资源回收。更多还原

【Abstract】 This paper conducts a research on the Formation mechanism and mechanicalcharacteristics of soft rock composite slope in surface coal mine and mining controltechnology. The importance is acknowledged that the ground stress and displacementwhich is cause by mining engineering is critical for the safety of a open-pit mine. Thedatabase of engineering geology classification for large-scale open-pit mines in Chinais established through statistical analysis, as the open-pit mines in China are classifiedgrounded on the geological conditions.The formula for excavation volume is deduced by the excavation-Heaping basicengineering steps, which further acts as the basis of the calculation formula of heightof dump. Combined with the basic parameters in Shengli Open-pit Mine and thedumping method, the curve of height of outer dump is obtained. According to theweak layer’s failure model and rheological properties, the calculation method isdetermined for the slope failure. Finite element analysis and numerical simulationsoftware are adopted to analyze the slope stability of weak layer, and it reveals thechanging law for soft slope stability during development.Heaping operation resulted in the compressed cement of bulk material by the roleof gravity, which enhances the density of bulk material. The shear strength increasesin a linear fashion by the compressed stress and the cohesion enhances in a quadraticfashion. Repeated Heaping brings about the long-term shear stress on the weak layer.The mechanical parameters of rock applied with a full stack pressure and compressionset was in a negative growth over time diminishing exponentially. Heaping work isbeneficial to the shear strength of the bulk material while detrimental to the base rock.The stress, which derives from repeated excavation and heaping in weak layers,brings about the unbalanced stress unloading in gob area and the base, which couldfurther result in the stress localization in the slope toe and the shaping of stress arch.The unbalanced stress resulting from heaping work promotes the development ofdeformation in weak layer. According to the rheological properties of weak layer, thedisplacement formula under piling load is obtained, by means of numerical simulation,as the stress-strain characteristics in weak layers is revealed.The comprehensive analysis of geological and hydrological conditions have beenconducted in the south slope in Shengli Open-pit Mine, and the distribution andcharacteristic of weak layers have also been outlined. The factor of safety for south slope is calculated with suitable section and lithological parameters. The miningschedule is designed according to the result, which will be beneficial to the recycle ofresource in weak layers.更多还原