锁固型边坡破坏演化机理及预警模型研究

发布时间：2018-07-10 09:56

本文选题：地质力学模型 + 锁固效应　；参考：《北京科技大学》2015年博士论文

【摘要】：高陡岩质边坡体内软弱结构面的分布、发育程度以及所处的应力场控制着边坡的变形和稳定性。大量高陡岩质边坡的滑动带内都存在着强度相对较高的岩桥段,这一岩桥段对边坡的稳定性起着关键的锁固作用,此类边坡称之为锁固型边坡。目前,在采矿和岩土工程领域,锁固型岩质高陡边坡分布广泛,数量众多,且其破坏演化过程又呈现出很强的渐进性和突发性,这使得开展此类边坡的稳定性评价和防灾减灾的研究工作具有非常重要的意义。本文以马钢(股份)南山矿业公司凹山采场边坡为研究背景,在构建采场边坡工程地质力学模型的基础上,结合室内试验、理论分析和数值分析等手段揭示了岩质边坡锁固段的锁固机理,从能量角度定量分析了锁固型边坡“滑动-锁固-剧动”的突发性破坏演化过程,并提出了一种锁固型边坡安全系数求解方法,在此基础上对凹山采场残矿回收过程中的边坡应力场、岩体损伤演化、稳定性分析以及预警模型的建立等问题开展了深入的研究,得到如下研究成果：(1)通过现场勘查、地应力场拟合和三维节理网络模拟技术,构建了凹山采场边坡工程地质力学模型,通过研究发现：采场边坡“上软下硬,上散下整”的特点具备储存边坡岩体残余峰降能量的岩体结构；F1断层贯穿南帮边坡,造成此坡体内出现明显的应力回转和卸荷区域,边坡应力集中效应明显,凹山采场属于典型的下部锁固型边坡。(2)自制类岩石材料试件并开展室内直剪实验,分别对不同贯通率、不同法向应力、不同岩桥排列方式、不同节理角度的锁固型试件的抗剪强度和扩展模式进行了研究,通过研究表明：锁固型试件的抗剪强度和扩展模式受节理和岩桥产状以及应力场的影响较为明显,其破坏演化过程呈现出很强的阶段性,岩桥核状区域裂隙的贯通标志着试件强度的丧失；试件产生残降应力差的同时,能量顺着剪切方向瞬间释放成为锁固型岩体突发性破坏的机理。(3)建立了锁固型边坡概化模型,根据系统能量积聚与释放过程建立了锁固型边坡动力失稳判据和能量演化公式,对锁固型边坡“滑动-锁固-剧动”的递进式动力失稳过程进行了定量描述,并提出了一种锁固型边坡安全系数求解方法,对锁固型边坡稳定性的影响因素进行了分析。(4)建立了节理岩体损伤演化分析模型及应用程序,并依据Rosenblueth原理对凹山采场深部残矿回收过程中不同阶段的边坡岩体三维随机损伤场进行了分析,揭示了节理型岩质边坡最终发展成为锁固型边坡的主要模式。(5)针对锁固型边坡的渐进性和突发性的特点研发了一套新型深部多点位移计,并结合MSR-300稳定性监测雷达,基于3DEC软件的二次开发和BP神经网络技术,通过位移反演建立了锁固型边坡三维时空预警模型,对采场残矿回收过程中的边坡稳定性进行了判定,并对锁固型边坡的破坏演化模式进行了预测分析。
[Abstract]:The distribution of the weak structural plane, the development degree and the stress field in the high steep rock slope control the deformation and stability of the slope. There are relatively high strength rock bridge sections in the sliding zone of a large number of high steep rock slopes. This rock bridge section has the locking effect on the stability of the slope, and this kind of slope is called the locking type. At present, in the field of mining and geotechnical engineering, the high and steep slope of locked rock is widely distributed and has a large number, and its failure and evolution process is very progressive and abrupt. This makes it very important to carry out the stability evaluation of this kind of slope and the research work on disaster prevention and reduction. On the basis of constructing the engineering geomechanics model of the mining slope, the locking mechanism of the locking section of the rock slope is revealed on the basis of the construction of the engineering geomechanics model of the slope of the stope slope, and the sudden destruction of the "sliding locking and the play movement" of the locked side slope is quantitatively analyzed from the energy point of view on the basis of the construction of the engineering geomechanics model of the slope of the stope slope. In this paper, a method for solving the safety factor of the lock type slope is put forward. On this basis, the stress field of the slope, the damage evolution of rock mass, the stability analysis and the establishment of the early warning model are studied. The following research results are obtained: (1) the in-situ stress field is simulated through the field investigation. The engineering geomechanics model of the slope of the fovea stope is constructed by combining with the three dimensional joint network simulation technology. Through the study, it is found that the slope of the slope "soft under the soft, up and down" has the rock mass structure that stores the residual peak of the slope rock mass, and the F1 fault runs through the southern slope, resulting in the obvious stress rotation in the slope. The stress concentration effect is obvious in the unloading area, and the concave hill stope belongs to the typical lower locking slope. (2) the self-made rock material specimen and the indoor direct shear experiment are carried out, and the shear strength and expansion mode of the locking type specimens with different penetration rate, different normal stress, different rock bridge arrangement and different joints angle are studied respectively. The study shows that the shear strength and expansion mode of the locking type specimen are more obviously influenced by the joints and the rock bridge and the stress field, and the failure evolution process presents a very strong stage. The penetration of the fissure in the core area of the rock bridge marks the loss of the strength of the specimen; while the specimen produces the residual stress difference, the energy follows the shear. The instantaneous release of cutting direction becomes the mechanism of sudden failure of locked rock mass. (3) a model of locking slope generalizability is established. Based on the energy accumulation and release process of the system, the dynamic instability criterion and energy evolution formula of the lock type slope are established, and the progressive dynamic instability process of the lock solid slope "sliding locking to play" is quantified. A method of solving the safety factor of the locking slope is presented and the factors affecting the stability of the lock slope are analyzed. (4) the damage evolution model and application program of jointed rock mass are established, and the three dimensional random loss of the rock mass in the different stages of the residual ore recovery process in the deep mining area is analyzed according to the Rosenblueth principle. The injury field is analyzed, and the main mode of the joint rock slope to be finally developed into a locking slope is revealed. (5) a new type of deep multi point displacement meter is developed for the progressive and sudden characteristics of the lock type slope, and the MSR-300 stability monitoring radar is combined with the two development of the software and the BP neural network technology. A three-dimensional spatio-temporal early warning model of locked slope is established by over displacement inversion, and the stability of the slope in the recovery process of the stope is determined, and the failure evolution model of the lock type slope is predicted and analyzed.
【学位授予单位】：北京科技大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：TD854.6

【相似文献】