土建專業(yè)畢業(yè)設(shè)計(jì)外文翻譯--孔隙水壓力作用下土坡的極限分析-wenkub
2023-05-19 14:38:25 本頁面
【正文】 of the soil until failure may be thought of as a possible method. However, such an elastoplastic analysis is rarely used in practice due to the plexity of the putations. From a practical standpoint, the primary focus of a stability problem is on the failure condition of the soil mass. Thus, practical solutions can be found in a simpler manner by focusing on conditions at impending collapse. Stability problem of natural slopes, or cut slopes are monly encountered in civil engineering projects. Solutions may be based on the slipline method, the limitequilibrium method, or limit analysis. The limitequilibrium method has gained wide acceptance in practice due to its simplicity. Most limitequilibrium method are based on the method of slices, in which a failure surface is assumed and the soil mass above the failure surface is divided into vertical slices. Global staticequilibrium conditions for assumed failure surface are examined, and a critical slip surface is searched, for which the factor of safety is minimized. In the development of the limitequilibrium method, efforts have focused on how to reduce the indeterminacy of the problem mainly by making assumptions on interslice forces. However, no solution based on the limitequilibrium method, not even the so called “rigorous” solutions can be regarded as rigorous in a strict mechanical sense. In limitequilibrium, the equilibrium equations are not satisfied for every point in the soil mass. Additionally, the flow rule is not satisfied in typical assumed slip surface, nor are the patibility condition and prefailure constitutive relationship. Limit analysis takes advantage of the upperand lowerbound theorems of plasticity theory to bound the rigorous solution to a stability problem from below and above. Limit analysis solutions are rigorous in the sense that the stress field associated with a lowerbound solution is in equilibrium with imposed loads at every point in the soil mass, while the velocity field associated with an upperbound solution is patible with imposed displacements. In simple terms, under lowerbound loadings, collapse is not in progress, but it may be imminent if the lower bound coincides with the true solution lies can be narrowed down by finding the highest possible lowerbound solution and the lowest possible upperbound solution. For slope stability analysis, the solution is in terms of either a critical slope height or a collapse loading applied on some portion of the slope boundary, for given soil properties and/or given slope geometry. In the past, for slope stability applications, most research concentrated on the upperbound method. This is due to the fact that the construction of proper statically admissible stress fields for finding lowerbound solutions is a difficult task. Most previous work was based on total stresses. For effective stress analysis, it is necessary to calculate porewater pressures. In the limitequilibrium method, porewater pressures are estimated from groundwater conditions simulated by defining a phreatic surface, and possibly a flow , or by a porewater pressure ratio. Similar methods can be used to specify porewater pressure for limit analysis. The effects of porewater pressure have been considered in some studies focusing on calculation of upperbound solutions to the slope stabi
畢業(yè)設(shè)計(jì)相關(guān)推薦
鄂ICP備17016276號-1