Stability Analysis And Construction Sequence Optimization Of Deep Cutting Subgrade Slope In Bazhun Heavy Haul Railay

With the rapid development of railway, highway, hydroelectric and otherinfrastructure construction, especially in the present development tendency of highspeed and heavy load of railway, the problem of slope stability analysis has become oneof the most complicated research topic in road engineering and geotechnicalengineering. At present, the cases of slope failure due to the improper constructionmethod and technology or not timely implementation of engineering measures and othercauses are too numerous to enumerate. The existing theoretical research is scattered, andfalls behind the engineering practice. Therefore, to carry out slope stability study ondeep cutting slope construction technology and method has important theoretical andengineering significance.In this paper, aiming at problems of the deep cutting slope stability problem in thenew Bazhun railway’s construction period, using the finite element method to analysethe effect of excavating process and supporting measures on slope stability, based on theestablished numerical model of deep cutting slope, deepening analysis is made to theinfluence factors theory of slope stability and especially the influence law caused by theconstruction method and different process, and the relative economic, safe andreasonable construction measures are proposed to optimize the construction excavationscheme.The work of this paper includes the following contents and conclusion：1) Combined with practical engineering, thorough analysis for preliminary designof the new Bazhun railway, engineering geological investigation data and constructionplans of subgrade design is carried out, while determination of calculation parameters ofdeep cutting slope stability analysis are made.2) Aiming at typical deep cutting section of the new Bazhun railway and based onthe finite element numerical simulation method, a deep cutting slope numerical model isestablished, then distribution law of deformation and stress of the key joint is analyzed,while research on stress characteristics of slope reinforcement measures; The safetyfactor of slope stability is obtained and evaluation for the slope stability is made throughintroduction of strength reduction theory.3) Making research on influence of cutting rock slope stability by rock bulk density, the shear strength and other parameters, it is found that the whole slope is stable withinthe bulk density range, and slope stability decreases with bulk density of rock increasing;with the increase of shear strength, slope stability safety coefficient and maximum valueof maximum principal stress increases, while the maximum value of total displacementincreases first then unchanged, slope face dose not enter the plastic stage and the rockslope stability is increasing.4）Through the dynamic simulation analysis of deep cutting slope formation andwhole process of reinforcement construction, based on comprehensive evaluation foreffect of the construction method and step to slope stability coefficient, slope toe stress,displacement increment of slope crest and other factors, a relative safety constructionplan is obtained which think layered and segmented excavation way of high slope ismore secure; then rational construction method is obtained by making fuzzy comparisonto different construction scheme from the economic, safety and applicability, and morereasonable construction scheme is formulated to guide the practice of construction.