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1.
高陡边坡稳定性的概率分析   总被引:2,自引:1,他引:1  
将概率方法应用于某高陡岩质路堑边坡的稳定性分析。通过适当降低岩土体的力学参数来间接考虑岩体节理裂隙的影响,并对加固后的边坡进行了同样的计算,认为加固后边坡处于稳定状态,与实际情况吻合。  相似文献   

2.
本文采用弹塑性有限元数值模拟方法对贵州某水电站左坝肩高边坡开挖高度310m施工期岩体应力应变状态进行分析研究,结合现场变形观测资料验证计算结果,对其稳定性进行评价并提出相应的加固措施。  相似文献   

3.
高陡边坡稳定性的概率分析   总被引:5,自引:0,他引:5  
将概率方法应用于某高陡岩质路堑边坡的稳定性分析。通过适当降低岩土体的力学参数来间接考虑岩体节理裂隙的影响,并对加固后的边坡进行了同样的计算,认为加固后边坡处于稳定状态,与实际情况吻合。  相似文献   

4.
本文介绍新滩滑坡后两岸边坡监测的工作,对边坡变形提出了趋势意见。认为新滩斜坡目前正处于整体稳定下的局部调整阶段,变形缓慢平稳,但要注视广家崖的危岩动态;链子崖仍有趋势性的倾江形变。5—6号缝围成的7万方危岩及江段的5万方危岩体尚有一触即崩之势,须加强监视。  相似文献   

5.
顺向岩质高边坡的稳定性通常较差,在工程上格外受到重视,利用锚索锚固是较为理想的加固方案。利用Sarma法对厦沙高速公路某段石英片岩顺向岩质高边坡在施加锚索和不加锚索两种工况下的应力特征和边坡稳定性系数进行对比分析。结果表明:不加锚索时,各条块底面正压力随开挖过程呈降低趋势,越靠近边坡顶部,各条块底面正压力受到开挖卸荷的影响越大,降低趋势越明显;条块底面正压力的降低使边坡抗滑力减小,当减小幅度较大时,边坡稳定性会受到明显影响,整个开挖过程中边坡整体稳定性系数呈下降趋势,最低为1.243;施加锚索能够增大条块底面正压力,提高条块底面的抗滑力,有效降低条块底面受到的剪切力,限制上部条块的滑动趋势,减小其对下部条块的挤压和相对错动,且随着开挖的加深,这种效应表现得越明显;对某个条块而言,施加锚索可以提高底面抗剪强度,降低底面和侧面剪切力、条块下滑力,从而提高边坡稳定性;施加锚索后边坡稳定性系数提高到1.630。综上所述,边坡开挖对于顺向岩质高边坡稳定性影响很大,而施加锚索加固可以显著提高边坡稳定性,达到加固边坡的目的。  相似文献   

6.
文章主要分析了露天煤矿边坡滑移变形的影响因素与监测方法设计原则,着重论述了强化边坡滑移变形监测的有效措施。加强滑移变形监测有利于掌握边坡地表的变形特点与趋势,提高了露天煤矿生产的安全性与可靠性。通过对边坡滑移变形监测的深入研究,能科学有效地预测边坡变形,减少安全事故的发生几率,提高露天煤矿企业的经济竞争力与社会竞争力,从而促进企业向着更好的方向发展。  相似文献   

7.
Σ岩体无显著变形时,很难从一组结构面中确定分离面λ置.为了科学加固此类Σ岩体,从2个工程案 例概化出存在不确定性分离面Σ岩体的稳定性分析模型,探讨了分离面λ置变化对倾倒式和滑移式Σ岩体稳定 性和剩余下滑力(矩)的影响规律,提出了ê固工程优化设计的标准.结果表明:两类Σ岩体潜在分离面的深度增 大时,倾覆力矩或剩余下滑力均呈现先增后减的趋势,稳定性最小λ置为关键分离面.ê固工程可采用长短不同 的ê固体,长ê杆穿过低于设计安全系数的潜在不稳定区,短ê杆穿过关键分离面和最大剩余下滑力的λ置,所 提出的优化设计方法对基岩山区地质灾害治理工程设计具有指导意义.   相似文献   

8.
文章主要以辽宁抚顺深大型露天煤矿闭坑前后地质特征、灾害成因的分析、防治等为基本的行文过程进行探讨,结果显示,煤矿闭坑前后地质灾害发生主要受到岩体的断层、松软结构、水文水量等制约,同时边坡的稳定性较差,在边坡表破容易发生局部变形,伴随开采深度的增加,半坡的可塑性逐渐增强,地表沉降等变形较大,要及时按照区域条件进行搬迁,避免地质危害的发生。  相似文献   

9.
综合考虑边坡坡高、角度、岩土体黏聚力、摩擦角和容重等因素对边坡稳定性的影响,通过有限单元应力法建立数值模
型,进行应力分析,最后计算得到边坡安全系数,这一方法将数值分析和极限平衡方法有机地融合在一起,达到优势互补的效果;
然后基于灰色关联分析法对有限单元应力法得到的数据建立数学模型,对各影响因素与安全系数进行关联分析,最后得到各影响
因素对边坡稳定性影响的敏感性。结果表明:影响边坡稳定性的因素敏感性依次为黏聚力、容重、摩擦角、边坡角度和坡高。利用
敏感性分析结果,可对边坡加固位置提出设计改进,将有限的加固措施加于敏感性较高的位置,能够更有效地提高边坡的稳定性。   相似文献   

10.
赣南地质环境复杂,沉积岩、岩浆岩与变质岩交叉并存;岩浆岩广泛分布,岩体破碎;褶皱、断裂构造发育;风化作用强烈,边坡稳定性差。研究这一地区的变形破坏模式,可以科学有效地对边坡进行防治。大量的野外调研显示,赣南边坡常见的类型主要有土质边坡、类土质边坡、岩质边坡和岩土二元结构边坡4类;赣南边坡常见的变形破坏模式主要有:沿原有结构面滑动、沿顶部拉裂-滑动、土体拉裂-崩塌、圆弧形滑动、坡面冲刷5类。沿原有结构面滑动破坏多见于岩质边坡、类土质边坡中;其余破坏模式多发生于土质边坡、类土质边坡、岩土二元结构边坡的土体部分。根据赣南边坡不同的变形破坏模式,分别提出了科学的防治对策;并针对赣南地区降雨量大、降雨持时长等特点,强调了在边坡的施工过程中应及时修建边坡排水系统,及时进行坡面防护。   相似文献   

11.
地下采煤会引起地表沉降、变形,甚至引发山体、河堤滑坡等地质灾害。采动坡体的稳定性研究一直是采矿工程中实际关心的问题。该文首先介绍分析了概率积分法移动变形稳态、动态预测模型以及基于极限平衡理论的单滑面采动坡体稳定性预测模型,提出了使用概率积分法结合Knothe时间函数对采动坡体稳定性进行预测分析的方法,并使用C#及XML Schema语言编制了相关的计算程序。最后,结合一个工程实例对采动坡体稳定性和动态变化过程进行了预测与分析,通过实测数据验证了提出方法的可行性,得出了采动引起的坡体下沉是影响坡体稳定性的主要因素,并提出了在坡体拉伸阶段进行注浆加固的方法。  相似文献   

12.
本文在分析横山山体地质条件及因地下采空而诱发出的山体变形破坏特征的基础上,对采空区地表山体的变形破坏进行了工程地质力学模拟研究。结果表明,横山山体之下3号煤层的采动坍陷是引起山体变形破坏的直接原因;毗邻山体的电厂区地表隆起变形破坏,是因采空区上覆岩层在坍陷时所产生的向电厂方向的蠕动,致使厂区地基土遭受挤压和变形的结果;随着3号煤层采动的结束及其上覆岩层坍陷过程的完成,电厂区将会恢复到稳定状态。 通过分析,山体岩层倾角增大时有无地下采空影响的山体变形破坏的不同特征,得出了同时具有地表侵蚀临空面和地下采空临空面的山体与仅有地表侵蚀临空面之斜玻的山体变形破坏是不同的。从不同模型材料所得实验结果的一致性,验证了此模拟实验在理论上和实际中都有很好的相似性。  相似文献   

13.
The buckling failure of stratified rock slopes intersected by a set of steep discontinuities that are approximately parallel to the slope surface is frequently encountered while constructing railways and roadways in mountainous areas. In this study, an analytical approach based on the energy equilibrium principle is presented to solve the flexural buckling stability of stratified rock slopes within the framework of multilayer beam theory. The generalized HoekBrown failure criterion is introduced to reflect the influences of slope size(scale effects) on the buckling stability. Subsequently, numerical and physical modellings from previous literatures are employed to validate the proposed approach. Furthermore, a practical case of Bawang Mountain landslide is also used for the comparative analysis. The study shows that the present analytical approach is capable to provide a more reasonable assessment for the buckling failure of stratified rock slopes, compared with several existing analytical approaches. Finally, a detailed parametric study is implemented, and the results indicate that the effects of rock strength, rock deformation modulus, geological strength index, layer thickness and disturbance degree of rock mass on the buckling failure of stratified rock slopes are more significant than that of rock type and slope angle.  相似文献   

14.
夏日哈木镍钴矿为大型镍钴硫化物矿床,现拟建大型露天采场,边坡采用分台阶式高边坡,最高边坡高度超过600m。该工程具有开挖成本高,边坡一但失稳后果严重的特点。为此需要选择一个即节约经济成本又保障整体边坡稳定的最佳边坡角。本文采取Geostudio软件中的Slope模块极限平衡方法对拟建露天采场假设开挖边坡角的整体边坡稳定性进行分析,提出最佳设计边坡角。 本次边坡角优化的思路:首先根据场地工程地质条件和拟建边坡的高度等因素将拟建边坡划分为5个区,选择典型边坡工程地质剖面并进行工程地质岩体分段,然后通过岩石强度指标折减计算(本文采用费辛柯法、M.Georgi法和经验法)给各分段的岩体赋予凝聚力、内摩擦角等计算参数,采用极限平衡方法(Geostudio软件中的Slope模块法)对不同角度下对各分区边坡的破坏形式及安全系数进行计算,最后提出了各分区边坡的最佳设计边坡角。  相似文献   

15.
Weak rock zone (soft interlayer, fault zone and soft rock) is the highlight of large-scale geological engineering research. It is an important boundary for analysis of rock mass stability. Weak rock zone has been formed in a long geological period, and in this period, various rocks have undergone long-term consolidation of geostatic stress and tectonic stress; therefore, under in-situ conditions, their density and modulus of deformation are relatively high. Due to its fragmentary nature, once being exposed to the earth’s surface, the structure of weak rock zone will soon be loosened, its density will be reduced, and its modulus of deformation will also be reduced significantly. Generally, weak rock zone can be found in large construction projects, especially in the dam foundation rocks of hydropower stations. These rocks cannot be eliminated completely by excavation. Furthermore, all tests nowadays are carried out after the exposure of weak rock zone, modulus of deformation under in-situ conditions cannot be revealed. In this paper, a test method explored by the authors has been introduced. This method is a whole multilayered medium deformation method. It is unnecessary to eliminate the relatively complete rocks covering on weak rock zone. A theoretical formula to obtain the modulus of deformation in various mediums has also been introduced. On-site comparative trials and indoor deformation modulus tests under equivalent density conditions have been carried out. We adopted several methods for the prediction researches of the deformation modulus of weak rock zone under in-situ conditions, and revealed a fact that under in-situ conditions, the deformation modulus of weak rock zone are several times higher than the test results obtained after the exposure. In a perspective of geological engineering, the research findings have fundamentally changed peoples’ concepts on the deformation modulus of weak rock zone, provided important theories and methods for precise definition of deformation modulus of deep weak rock zone under cap rock conditions, as well as for reasonable engineering applications.  相似文献   

16.
Deep-seated large-scale toppling failure presents unique challenges in the study of natural slope deformation process in mountainous regions.An active deep-seated toppling process was identified in the Erguxi slope located in southwest China,which affected a large area and damaged critical transportation infrastructure with the volume of the deforming rock mass exceeding 24×10~6 m~3.It poses significant risks to the downstream Shiziping Hydropower Station by damming the Zagunao River.Field investigation and monitoring results indicate that the deformation of the Erguxi slope is in the advanced stage of deep-seated toppling process,with the formation of a disturbed belt but no identifiable master failure surface.It was postulated that the alternating tensile and shear strength associated with the hard/soft laminated rock strata of metasandstone and phyllite layers preclude the development of either a tensile or shear failure surface,which resulted in the continuous deformation and displacement without a catastrophic mass movement.The slope movement is in close association with the unfavorable geological conditions of the study area in addition to the construction of transportation infrastructure and the increase of the reservoir level.On the basis of the mechanism and intensity of the ongoing toppling deformation,a qualitative grading system was proposed to describe the toppling process and toevaluate the slope stability.This paper summarized the field observation and monitoring data on the toppling deformation for better characterizing its effect on the stability of the Erguxi slope.The qualitative grading system intends to provide a basis for quantitative study of large-scale deep-seated toppling process in metamorphic rocks.  相似文献   

17.
采空区地表山体侧向变动,不同于一般天然山坡,也与采空区一般上覆岩层的变形破坏有异;它是二者复合机理的效应。本文在分析考察了毗邻电厂的横山顺倾构造山体、剖析了地下采空情况认为:山体侧向变动中,软弱夹层有决定性作用,变动范围、速率和规模与地下采空有关;并利用地质力学模型试验和数值模拟,探索了采动引起山体应力场及变动规律。结果表明,山体岩层的变形、位移、破坏、由直接顶板向地表发展,采空坍陷诱发了软弱夹层的蠕滑,则产生山体侧向滑移;电厂区地表隆起变形是山体侧向滑移挤压地基土的反映。通过现场实际调研、变形观测资料分析与数值模拟和模型试验的对比研究,提出了“坍落拱梁”的成生效应、挤压蠕滑效应、失稳效应;揭露了顺倾构造山体在采空影响下,具有地表、地下的“复合临空面”的“复合应力场”中“复合变动”的“复合机理”;并提出这种山体侧向变动机理的典型地质模式,借以论证山体稳定性。  相似文献   

18.
During the construction of some large-scale rock engineering, high-steep slopes and insufficient slope stability induced by unloading fissures are often encountered. For the reinforcement of these slopes, some techniques (including conventional pre-stressed anchoring cable and unconventional anchoring hole) are usually uti- lized, however, having several obvious defects. Thus, it is very difficult for a designer to design an efficient reinforcement scheme for the high-steep slopes. For this reason, the authors develop the pre-stressed anchoring beam technique, in which tensile capacity of pre-stressed structures are fully utilized. It is analyzed that the new technique is characterized by multi-functions, including engineering investigation, efficient reinforcement, drainage, monitoring and urgent strength supplement, and hoped to be extensively applicable in the reinforcement of high-steep slopes.  相似文献   

19.
During the construction of some large-scale rock engineering, high-steep slopes and insufficient slope stability induced by unloading fissures are often encountered. For the reinforcement of these slopes, some techniques (including conventional pre-stressed anchoring cable and unconventional anchoring hole) are usually utilized, however, having several obvious defects. Thus, it is very difficult for a designer to design an efficient reinforcement scheme for the high-steep slopes. For this reason, the authors develop the pre-stressed anchoring beam technique, in which tensile capacity of pre-stressed structures are fully utilized. It is analyzed that the new technique is characterized by multi-functions, including engineering investigation, efficient reinforcement, drainage, monitoring and urgent strength supplement, and hoped to be extensively applicable in the reinforcement of high-steep slopes.  相似文献   

20.
The study of artificial slope stability has been a key item of geological engineering projects. Though more evaluation methods are available,result of stability evaluation simulation does not explain the actual prob- lem owing to the diversified geological engineering factors and complexity. The author made a detailed study based on surveys of large amount of geological engineering research on Donggang Power Plant slope project,dis- cussed the comprehensive factors influencing the project,and gave analytical calculation and evaluation to the improved response surface of the slope project. The study result shows that the slope is stable,which can pro- vide scientific basis for designing the slope.  相似文献   

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