| In recent years, as the country's rapid economic development, energy, road and rail transport, Water Resources and Hydropower, nuclear power and other projects both quantity and size has increased significantly in these projects during the construction and use of the slope failure the case of steady destruction have occurred, to the people a huge threat to life and property, and even affect the project construction and the use of normal, causing huge losses to the national economy, so the slope stability evaluation and management of geotechnical engineering has been sector one of the important issues of concern.In this paper, a study of slope for the stratified rock, layered rock mass is distributed in the native structure of a dominant surface sedimentary rocks, extrusive rocks and metasediments. In land area in China, has a layered structure of sedimentary rocks accounted for 77.3%. In slope engineering, the structure has a layered rock slope slope is a common structure types, such as helped open pit slope roof, Slope Water and road, rail slope and so on. Therefore, the construction of various projects in the line is bound to encounter a lot of layered rock slope stability problems. In 1995, Chiang Jazz and other light railway on the domestic trunk lines 12 rock slope investigation, the railway is mainly rock landslide slope angle is less than the slope angle of the layered structure of layered rock landslides. Angle greater than 15 degrees in the rock situation, basically had the destruction of bedding slip phenomenon. Therefore, in the layered rock slope failure modes, sliding failure bedding is top priority.I summed up in the previous analysis for the slope failure, based on the slope for the stratified rock mass instability mechanism and governance issues of a more systematic analysis and research. Focus was on the layered rock slope method of cable management, including the anchor support the theory of layered rock slope analysis and anchor support elements for supporting the effect of combining sets Dan Highway K6 +059 Projects section, on the same slope to dipping layered rock anchor support the stability of the finite element analysis and anchor support the stability before and after treatment compared to last, layered rock slope Analysis of factors affecting the law of instability and a variety of internal and external causes of the meta-analysis, for the future treatment of various types of layered slope to provide a theoretical basis and the related engineering advice. The main work and conclusions are as follows:(1) layered rock slope on the classification, from the geology and rock mechanics point of view angle by changing the mechanism of various types of damage, which made five three common failure modes and failure modes of geomechanics, as well as failure modes and their different mechanisms of rock failure under inclination. And dipping for the same to the layered rock slope instability features developed analytical models to analyze the mechanical failure mechanism, drawn layered rock slope failure occurred bedding slip limit state equation.(2) analysis of the layered rock mass effect of the slope with the cable anchor support the length of the relationship between the angle and density. Calculated using MATLAB programming software curve fitting calculation, the slope safety factor and the various factors affect the function of a single factor, drawing a function of the single factors of the element. Then discussed the anchor in the 90°angle under the conditions, safety factor and cable length and anchor two-dimensional density function, and the relationship has been calculated maximum error value.(3) established a set of Dan Highway K6 +059 layered rock slope section of elastic-plastic finite element analysis model, the use of plastic shear strength reduction finite element method, by means of finite element software, the state of slope failure analyzed. Strength reduction FEM analysis the basic principles of the slope is to the actual strength parameters of rock mass divided by a reduction factor, after the reduction of strength parameters values into the finite element method, when the intensity parameters caused by the decrease of the finite element calculations do not converge, indicating the rock to reach the critical limit state, shear failure of slope. The method has greatest advantage of the slope safety factor can be solved directly without the need to assume that sliding surface. (4) by calculating the slope of the decline in force, according to Cable support before the regular analysis of the set of Dan Highway K6 +059 layered rock slope section presented a reasonable anchor support programs. Established a layered rock slope anchor support plastic two-dimensional finite element analysis model, using the strength reduction plastic finite element method, by means of finite element software, support for the cable was lost after the slope stability analysis. And anchor support for the slope before and after the maximum horizontal displacement, maximum elongation, maximum horizontal stress, maximum vertical stress, plastic strain and edge safety factor, etc., made a comprehensive comparative analysis.(5) Based on the layered rock slope instability factors of law analysis, the following conclusions:a. layered rock slope failure in large part by the strength of weak structural parameters of the control plane, the higher the strength of weak structural plane, the slope more stable.b. rock slope angle on the instability of stratified rock mass has obvious influence. When the strata dip angle 25°-40°when the bedding prone to landslides, which, when the rock is about 35°inclination, the slope of the stability of the worst; when the rock angle greater than 45°or less than 15°, slope stability well, not usually slip bedding.c. In the conventional design slope rate conditions, thickness of the layered rock slope stability safety factor has little effect, but in the actual project may lead to slope failure mode differences.d. layered rock slope instability is a very complex issue. The quality of its stability but also with the excavation depth and excavation area, surface water and groundwater, rock weight and degree of the natural slope angle of the mountain, and many other factors. Only on external factors for integration of these internal analysis of characteristics of slope instability can be more thorough. |
