【作者】 李娜；

【导师】 曹平；

【作者基本信息】 中南大学 ， 地下空间科学与工程， 2011， 硕士

【摘要】 随着经济的快速增长,目前对资源的需求越来越大,但是事实上我国的浅部资源已经面临危机,深部资源则存在较大潜力,因此大量的矿业开采已经开始向深部发展。矿山深部岩体由于埋深较大、原始应力高,处于非常复杂的特殊环境中,因此往往呈现出明显的流变性。加之矿山深部通常地下水发达,深部岩石长期浸泡于地下水当中,使得岩石的性质更加不稳定,加速围岩的破坏,造成人员财产损失。因此对含水状态下的深部岩石性质的研究显得十分必要。本文针对金川二矿区深部岩石的力学特性与流变性质进行探讨,对岩石在自然状态下与饱水状态下进行长期流变试验,从宏观上分析水对岩石力学特性与流变性质的影响,根据试验结果建立了能反映岩石流变特性的本构模型。本文主要研究内容如下：(1)从金川二矿区深部采集岩石样本,加工成标准试件,对试件得物理特性进行测定。(2)采用RYL-600微机控制岩石剪切试验机对试件进行了单轴压缩和剪切试验。分析了试件的抗压强度、变形模量及泊松比的变化规律以及岩样的变形特点、强度特征和破坏规律,得到了各种岩石试样的基本力学参数,为进行岩石蠕变试验和数值计算提供了依据。(3)采用分级增量循环加卸载方式对金川二矿区深部岩石在自然和饱水两种状态下进行流变试验,根据蠕变实验所得的曲线,按照可恢复的瞬时弹性应变、滞后粘弹性应变、不可恢复的瞬时塑性应变与粘塑性应变进行数据分析,得出了深部岩石在高应力条件下的流变特性。(4)引入一个非线性粘塑体和广义的Kelvin模型串联,构成一个七元件非线性粘弹塑性蠕变模型。通过此模型可以较好的描述金川二矿区深部岩石的蠕变特性。采用阻尼最小二乘法根据流变试验曲线对模型进行了参数识别。更多还原

【Abstract】 With the rapid economic growth, people demand more and more resource, but in fact our shallow level resources have been facing a crisis, while the deep resources are there is a big potential, so a large number of mining engineering has already turned to the depth level. Rock engineering in depth level own its special features-high original stress, rheological property of rock is more evident with special complex environment. Long-term immersion coupled with well-developed deep water, the nature of rock is more unstable, which accelerate the destruction of surrounding rock, causing big damage to people and property.Therefore, research works to the properties of rock under deep water become very necessary. Long-term experiments have respectively been conducted to analyse the deep rock’s mechanical and rheological properties in the natural state and water-saturated state, which was collected from JinChuan NO.2 district. And then the rheology constitutive model of rock is proposed, undering analysis of macroscopic mechanical properties of water on rock properties and rheological effects. The main research works are as follows:(1) Standard test blocks are processed from the deep Earth rocks, collected from JinChuan NO.2 district. Meanwhile, experiments on the physical properties of the rocks are measured.(2)Both conventional uniaxial compression test and shear test are conducted on RYL-600 testing machine. This article analyzes the deformation of rock samples, strength characteristics and failure law and the compressive strength of specimens, deformation modulus and poisson ratio variation law,obtains a variety of basic mechanical parameters of rock samples for the creep test which will provide a basis for numerical calculation.(3) Creep experiments have been conducted by adopting multi-step incremental cycling loading and unloading method and using rock samples collected in Jinchuan No.2 mining area in air and saturated states. According to the experimental creep curve, data of experiments had been processed according to instant elastic strain, visco-elastic-plastic strain, instant plastic stain and visco-plastic stain, respectively. Deformation feature of visco-elastic-plastic rock in depth level have been derived.(4)A new nonlinear viscoplastic body is proposed, which is in series connecting with generalized Kelvin model, we can construct a new seven-component nonlinear viscoelastoplastic rheological model of rock. The model effectively describes the mechanics characteristics of Jinchuan No.2 district. The model parameters are identified successfully through the damped least square method according to the creep test curves.更多还原