【作者】 陈云娟；

【导师】 谭云亮； 赵同彬；

【作者基本信息】 山东科技大学 ， 固体力学， 2010， 硕士

【摘要】 岩体工程的变形破坏往往要经历一个持续的发展过程,研究岩体的蠕变特性对围岩稳定性控制具有重要意义。由于自然状态下的岩体均一性较差且取样困难,而采用类岩石材料代替原岩试件进行室内实验研究是比较合理的解决途径。本文采用理论分析、相似模拟试验、蠕变试验和数值模拟相结合的综合研究方法,对类岩石材料的蠕变本构进行了研究。以山东新汶矿区-1100m水平粉砂岩为试件原型,相似比尺为20：1。通过颗粒压缩量分析,研制相似模拟模具。选择合适的类岩石材料,进行大量反复的配比试验,确定最佳配比并配制标准试件。对试件进行单轴抗压强度测试,进而确定蠕变试验的初级荷载。分析表明：五组试件中,当松香酒精溶液摩尔浓度为30%时,类岩石试件的强度最大,平均极限荷载为5.20KN,平均单轴抗压强度为2.65MPa。本文将蠕变试验的初级荷载定为极限荷载的21%,即1.07KN。使用RLJW-2000流变试验机对类岩石试件进行恒温恒湿条件下的室内长时蠕变试验。试验结果表明：施加荷载越大,类岩石试件的蠕变变形越明显,试件的平均破坏应力阀值为瞬时强度的92%；荷载低于破坏应力阀值时,试件蠕变曲线只出现初期蠕变和稳态蠕变两个阶段,荷载超过破坏应力阀值时,试件加速破坏阶段较为明显,具有完整的蠕变三阶段。根据蠕变曲线,自定义非线性CYJ模型,该模型在一定条件下可以蜕变为线性Burgers模型。分析FLAC3D二次开发的基本原理、步骤及关键技术。将CYJ模型本构方程由一维推导至三维差分形式,并嵌套到FLAC3D中,完成软件的二次开发。应用CYJ模型对类岩石试件的蠕变性进行FLAC3D数值模拟,结果表明：数值模拟与试验结果大致吻合,CYJ模型能够较好的描述岩体的蠕变三阶段。更多还原

【Abstract】 Deformation and failure of rock projects often goes through a continuous development process, studying on rock creep characteristics is important for surrounding rock stability control. As that uniformity of natural rock mass is poor, sampling is difficult, and doing laboratory research with similar rock materials instead of original rock specimens is a more reasonable solution. A comprehensive approach combined with theoretical analysis, similar simulation test, creep test and numerical simulation is used in this paper, to study the creep constitutive of similar rock materials.Shandong Xinwen Mine-1100m level siltstone is the prototype test piece, with similar ratio 20:1. Similar simulation mold is developed through the compression amount analysis of particles. Suitable similar materials are selected, a large number of repeated ratio tests are carried out, the optimum ratio is determined and standard specimens are made. Uniaxial compressive strength of specimens is tested and the primary load of creep test is determined. The results show that, among the five groups of specimens, compressive strength of similar rock specimens is the largest when rosin alcohol solution’s molar concentration is 30%, the average ultimate load is 5.20KN and average uniaxial compressive strength is 2.65 MPa. The creep primary load is decided to be 21% of ultimate load, which is 1.07 KN.The creep tests of similar rock specimens are carried out under constant temperature and humidity conditions by RLJW-2000. Results show that, the larger load, the more obvious creep deformation is, the average failure stress threshold is 92% of instantaneous intensity; when load is below the failure stress threshold, only initial creep and steady creep appeare on the curve, when load is above the failure stress threshold, the accelerating destruction stage of specimen is more obvious, with a complete three-stage creep. Custom nonlinear CYJ model is made according the creep curve, which can be transformed into linear Burgers model under certain conditions.The basic principles, steps and key technologies of FLAC3D secondary development are analyzed. CYJ constitutive equation is derived from one-dimensional to three-dimensional differential form, and is nested into FLAC30, the secondary development of FLAC3D is completed. Using CYJ model, similar rock specimen’s creep characteristics are simulated by FLAC3D. Results show that, numerical simultaion is roughly in line with creep tests, CYJ model can describe rocks’three creep stages well.更多还原