Study on Mechanics Parameters of Structural Planes and Optimized Design of Engineering Treatments on Consequent Slope in GuangBa Expressway
|School||Chengdu University of Technology|
|Keywords||consequent slope structural plane mechanics parameters engineering treatment|
The construction and the development of highway is a windvane of the state’s economy level of development. Our country is mountainous, in order to overall development regionally and builds harmonious society, which the points of convenient, quick, highly effective highways’ construction will change from plain area to mountainous area.In the humanity engineering construction history process, the deformation of slope was an important topic which puzzled engineering construction, and the problem was prominent on expressway constructing in mountainous area especially. So, study the road side slope as object has significant meaning. The structural plane of slope’s rock mass is one of important factors in controlling the stability of the slope. The reseach of the structural plane is deficient relatively, therefore this article choice structural plane mechanics parameter research as primary content.The GuangBa highway is an inter-provincial tie line connecting branch lines. There are lots of geologic bodies between Guangyuan～Puji(K0～K87), and there are 54 sections of consequent slope along the highway, which are easy to be destructed. This kind of side slopes’ stability is often related to the structural planes characters, thus the research of mechanical parameters in structural planes is very important to estimate the stability of the slopes and Choice designing proposals.This article based on studying of slopes’ essential features, structural plane mechanics characteristics and the influencing factors of consequent slope, structural plane mechanics parameters. Then studied the slope distortion destruction mechanism and its stability and proposed the optimization design plan of protective measures of the slope.The concrete research contents including the rock mass structure and the distortion destruction mode, the structural plane project classification, the structural plane aeolotropy and the size effect research, the structural plane investigation statistics, the structural plane theory of strength formula research, the physical simulation about the distortion destroys mechanism, the finite element simulation to show the excavating process and so on.Through a series of concrete research, draws the following main conclusion: (1) The geological features of slopes studied mainly to divide into: The hard rock consequent slope, the hard nip soft rock consequent slope, the hard and soft rock consequent slope, the soft nip hard rock consequent slope and soft rock slope. The model of its deformation failure is slip-crack primary, and collapse,break-fall are subsidiary .(2) the structural plane mechanical properties influencing factors contain the plane’s shape, the structural plane’s union and its backfill condition, the structural plane’s continuity, the structural plane’s normal stress, the hydrogeological conditions and the weak band including the structural plane and so on. The investigation and study indicated that the structural planes in research area are mostly IV level, and the structural plane fluctuation rough degree influences structural plane parameter primarily.(3) Through minute analysis in the structural plane fluctuation roughness, proposed using the structural plane slope gradient expected value and height expected value to describe the structural plane profile curve, and regress it to the relational function of the Barton standard, caused it to be advantageous for the project application.(4) Based on the parameter research, analysis the typical slopes stability qualitatively and quantitatively. Its parameters gain from testing method, project analogism, theoretical formula.(5)The side slope excavates the numerical simulation result to indicate: The research area slope along with cutting depth’s increase, the toe of slope shearing stress concentrates and the scope unceasingly expands unceasingly, and biggest principal stress and slope face parallel, increases gradually to the depth portion, is proportional with the gravity, stress magnitude scope value generally below 0.5MPa, but has not presented the plastic zone, so the slope will not destroy wholly, only have partial discharge back distortion.(6) Optimized design the typical cut slope slope, finally indicated that the existing design tends to be conservative, still can be further optimized.This research has provided one kind of mentality for the study of slope structural planes and the investigation into stability, its achievement can be used in the GuangBa expressway construction directly, meanwhile it can be broadly used for reference.