【作者】 阎宗岭；

【导师】 邱贤德；

【作者基本信息】 重庆大学 ， 采矿工程， 2003， 博士

【摘要】 堆石体是一种有一定级配、无凝聚性、渗透能力很强的摩擦型集合料，并具有独特的物理力学特性。其特殊性主要是因为它是由颗粒和孔隙组成，其性质与颗粒的大小、形状及分布特征有关，并且在载荷作用下，这些参量将不断发生变化，堆石体物理力学性质也随之改变。论文采用散体力学、颗粒力学的相关理论对堆石体的强度和变形机理进行研究，并考虑到堆石体内部微观结构的变化特征，将微观结构的特征参数与宏观力学量统一起来，建立相适应的力学模型，将微观与宏观联系起来，进一步完善了对堆石体的研究。论文完成的主要研究工作有：有关堆石体物理力学性质方面，在已有研究成果基础上，对相关研究成果进行综合比较、分析、研究、总结，并借鉴散体力学、颗粒力学和统计力学相关理论，把有关堆石体的物理力学性质的研究成果融汇成了一个较完善的基础理论体系。从岩石的破碎机理出发，建立了堆石体粒径分布的对数正态分布模型，可以较好的预测爆破堆石体的粒径分布。对堆石体的物理力学性质进行了较全面的试验研究，包括现场测试与分析、现场大型碾压试验、原位剪切试验、渗透试验、击实试验、压缩试验、三轴剪切试验等，对堆石体的颗粒分布、抗剪强度、渗透特性、压缩性以及沉降特性进行了研究，丰富了理论研究内容，为工程应用提供了科学依据。从堆石体的组构特征出发，以数理统计为工具，研究了颗粒间的接触力以及接触力的法向分布，得出了颗粒间接触力的概率分布。研究了堆石体的力学性质与颗粒的空间堆积方式、孔隙的大小及孔隙的空间分布之间的关系。运用散体颗粒力学和数理统计理论，从颗粒的空间堆积形态出发，分析颗粒间的接触关系、接触力，并建立了堆石体颗粒间的局部微观接触力与宏观应力之间的关系。从堆石体颗粒的微观结构出发，建立了堆石体的刚性接触模型，将颗粒间的接触力同局部应力联系起来，建立了堆石体的局部本构模型。以堆石体局部本构关系为基础，并从微观到宏观，建立了堆石体的二维、三维本构模型，把堆石体的微观颗粒组构特征与其宏观物理力学特性联系起来，为进一步研究堆石体物理力学特性奠定了理论基础。通过理论分析、现场监测和数值分析等手段，研究了堆石体内土压力的分布状况，对堆石体的成拱机理进行了理论研究，并分析了堆石体对其内部构筑物安全性的影<WP=4>响。以堆石体的成拱效应为算例，以数值分析为手段，对堆石体填筑结构的土压力分布进行了数值模拟，验证了堆石体成拱效应。以几个不同工程为实例，充分阐述了堆石体在工程中的典型应用情况，充分应用了堆石体压实性能好、透水性强、填筑密度大、沉陷变形小、承载力高、稳定性好等优良工程特性，体现出了堆石体在工程中良好的安全、经济、社会和环境效益。工程应用表明堆石体是一种安全、经济以及具有良好社会、环境效益的工程材料。更多还原

【Abstract】 Rockfill is a cohesionless frictional aggregate material with certain gradation, high seepage velocity and has particular physical and mechanical characteristics since rockfill is mainly composed of particles and void. Its properties are related to particle’s size, shape and distributing character. These particle’s parameters will change when force is put on, and the characteristics of rockfill change too. The strength and deformation mechanism are studied in this thesis on the base of discrete mechanics and granular material mechanics considering the change of microstructure of rockfill.The adaptive mechanical model is established combining characteristic parameters of microstructure with macro mechanical parameters. The thesis enriches the research of rockfill, and the main achievements are as follows: A more integrated fundamental theory system for rockfill is built up upon synthetically compare, analysis, study and summarization of the research achievements about physical and mechanical characteristics of rockfill through introducing related theories of discrete mechanics, granular material mechanics and statistical mechanics.The Log-normal distribution model of rockfill particle is established based on rock fragmentation mechanism. It well forecast the gradation distribution of blasted rockfill.Comprehensive experimental research is carried out in this thesis to study the particle gradation, shear strength, seepage ability, compress ability and settlement of rockfill including in situ test and analysis, large scale roll test, in situ shear test, seepage test, compaction test, compress test, triaxial shear test and so on. The results are helpful to further research and provide necessary data for engineering project.Probability density of contact force is acquired through research contact force, contact force normal and fabric characteristics of rockfill by statistical mechanics to study the relationship between physical and mechanical characteristics of rockfill and packing style of particles, void and its dimensional distribution.Relationship between local micro contact force of particle and macro stress of rockfill is studied through discrete mechanics and statistical theory by analyzing of contact relation and contact force from dimensional packing of particle. Put forward rigid contact model that can connect contact force with local stress and establish local constitutive model based on micro structure of rockfill particle. Two dimensional and three dimensional constitutive models for rockfill are built up on the base of local constitutive relation. It connects particle micro fabric with macro mechanical response and can be the base for further research.Through theoretically analysis, in situ monitor and numerical analysis to study the<WP=6>soil force distributing status and investigate the arching action of rockfill and analyze the influence of rockfill on its inner structures. Engineering examples approve that rockfill has excellent engineering characteristics, such as good compactness, strong seepage ability, high density, low sedimentation, high bearing capacity, good stability and so on. It shows well safe benefit, economic benefit, social benefit and environmental benefit. So rockfill is a safe and economical engineering material with well social benefit and environmental benefit.更多还原