【作者】 王光进；

【导师】 杨春和；

【作者基本信息】 重庆大学 ， 采矿工程， 2011， 博士

【摘要】 超高台阶排土场的建设能大幅度减少矿业占地,达到资源开发与环境效益双丰收的目的。然而,超高台阶排土场边坡不同于一般的土质边坡,其具有一个突出特点:排土场堆积散体具有“明显的粒径分级”。本文采用现场试验、室内试验、数值模拟相结合的综合性研究方法,针对排土场堆积散体的分布规律及其力学特性进行深入系统的研究,并以江西德兴铜矿西源岭413m台阶排土场为工程实例,开展了超高台阶排土场边坡稳定性计算分析,取得了如下一些成果:1)本文基于现场的颗分试验结果,分析了排土场堆积散体的粒径分布规律。同时,修正了Rosin-Ramuler模型,并利用现场粒径调查结果验证了此修正模型。然后,对修正的Rosin-Ramuler模型中的“分布参数d值”进行了重新定义,并分析了d值与排土场高度之间的关系。从而建立了排土场坡面散体某粒径的筛下相对含量与排土场高度之间的函数关系式。2)利用改装的大型直剪试验仪,进行了不同垂直压力、不同粗粒含量下的颗粒破碎试验研究,分析了垂直压力和粗粒含量与颗粒破碎率之间的变化关系,并在此基础上建立了粗粒土的应力-破碎描述模型。同时,开展了饱和与非饱和样、浸泡土样的颗粒破碎试验研究,分析了不同含水量以及长期浸泡对粗粒土颗粒破碎的影响。3)借助大型直剪仪进行了粗粒土的剪切强度特性试验研究,分析了不同粗粒含量和不同垂直压力下的剪应力-应变曲线变化规律。并结合粗粒土的颗粒破碎研究成果,分析了粗粒含量、垂直压力和颗粒破碎对粗粒土内摩擦角值的影响。4)本文基于元胞自动机方法开发了能模拟三种元胞状态随机分布的“HHC-CA模型”。从而为虚拟三轴试验室和表征“明显粒径分级”的超高台阶排土场边坡计算模型的建立奠定基础。5)完整地提供了一套粗粒土三轴数值模拟试验方法。基于开发的“HHC-CA模型”,利用衍生出的“HHC-Soil模型”制备不同“试样颗粒初始架构”的粗粒土试样,以表征粗粒土各粒组分布的不均匀性和随机性。然后,借助FLAC-3D进行粗粒土三轴数值模拟试验,并利用“室内三轴试验”结果验证了粗粒土三轴数值模拟试验的可行性。分析了“试样剪切带内的砾石含量”和“试样砾石含量”对粗粒土内摩擦角的影响。6)提出了一种崭新的考虑“明显粒径分级“的超高台阶排土场边坡稳定性分析方法。本文针对西源岭413m台阶排土场,结合衍生的“HHC-Granular模型”和现场粒径调查结果建立了表征“明显粒径分级”的排土场边坡计算模型,并对超高台阶排土场边坡进行了稳定性分析研究,探讨了采用“单台阶全段高排土”和“全覆盖式多台阶排土”的排土场边坡安全稳定性。更多还原

【Abstract】 The construction of super-high bench dumping site can decrease substantially mining space and attain the goal of both resource exploitation and environmental benefit. Nevertheless, the super-high bench dumping site which is characterized by the particle size grading is different from the usual soil slope. This thesis studies the grading rules and mechanical characteristics of granular coarse-grained materials in dumping site by using the following methods: the on-site investigation of grain size, laboratory test and numerical simulation. Baesed on the research pobjec of Xiyuanling 413m step dumping site of the Dexing copper mine in Jiangxi province, the slope stability of the super-high bench dumping site with the obvious particle size grading is fully researched. The main achievements of this dissertation are as follows:1)The article analysed the particle size distribution of dumping site according to the on-site experiment of particle size. Meanwhile, the Rosin-Ramuler model was revised and the revised model was verified by use of the result of on-site particle size . The distributed parameter d value of the revised Rosin-Ramuler model was redefined and the relationship beween the d value and the dumping site height was established. This thesis established the function equation beween the undersize relative content at a certain particle size with the slope of dumping site and the height of dumping site.2)With the refitted large-scale direct shear apparatus, the particle breakage experiment of different vertical pressure and different coarse-grained contents had been completed, and the relationship between upright stress and coarse-grained content and the particle breakage index was analysed. and based on that, The stress-broken description model was established. Meanwhile, the particle breakage of saturation samples and unsaturated samples and soaked samples was studied by experiments, and the effect of different moisture contents and long-term soaked to the particle breakage index was analyzed.3)The mechanical characteristics of coarse-grained soil was studied through the large-scale direct shear apparatus, The thesis analyzed the changing regularity of shear stress and strain curve in the different vertical pressure and different coarse-grained contents. the effect of coarse-grained contents and vertical pressure and particle breakage to the internal friction angles of coarse-grained soil was analyzed combining the research results of particle breakage with coarse-grained soil. 4)According to cellular automata method, the HHC-CA model which could randomly simulated three cellular states was developed. And it laid a foundation for the building of virtual triaxial lab with coarse-grained soil and slope computation model of super-high bench dumping site with characterizing the obvious particle size grading.5)This thesis fully provided a new test method for the triaxial numerical simulation test of coarse-grained soil. Based on the HHC-Soil model which derived from the developed the HHC-Soil model, we generated the coarse-grained soil samples of different initial fabric of grain to characterize the heterogeneous and random distribution of coarse-grained soil grain group.Then by means of FLAC-3D,the triaxial numerical simulation tests were completed and the feasibility of virtual triaxial test with coarse-grained soil was verified by use of the indoor triaxial test results. The effect of the gravel contents of samples shear band and samples on the internal friction angle was discussed.6)A new method of slope stability analysis with the super-high bench dumping site which was considered the obvious particle size grading was presented. On the basis of the derivative HHC-Granular model and on-site survey of granular size distribution,the slope model, which was used to carry through the slope stability analysis, was established according to the Xiyuanling 413m step dumping site considering the features of particle size grading. Through the slope stability analysis, The slope security and stability of dumping site with adopting the piling up pattern of“whole section height dump of single-step”and“full overlay dump of multi-step”were discussed.更多还原