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551.
The assessment of forces exerted on walls by the backfill is a recurrent problem in geotechnical engineering, owing to its relevance for both retaining systems and underground structures. In particular, the work by Arias and colleagues, and later also the one by Veletsos and Younan, among others, becomes pertinent when considering pressure increments on underground structures triggered by seismic events. As a first step, they studied the response of a rigid retaining wall resting on rigid bedrock subjected to SV waves, introducing some simplifying assumptions. This paper presents the exact solution to this reference problem. The solution is given in horizontal wavenumber domain; hence, it comes in terms of inverse Fourier transforms, which can be approximated numerically in Mathematica, which in turn are verified against finite-element simulations. Specific features of this exact solution that were not captured by prior engineering approximations are highlighted and discussed. 相似文献
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Summary The computer aided design of geosynthetic reinforced soil walls is reported. The magnitude of tensile forces in the geosynthetic reinforcement has also been studied under external vertical and horizontal strip loads. 相似文献
554.
J. Oliphant 《Geotechnical and Geological Engineering》1992,10(4):273-289
Summary This paper considers the safety of geotechnical structures using various design philosophies which include the global safety method and a number of limit state design methods. The methods are considered individually and their treatment of uncertainties of design briefly discussed in terms of parameter and system uncertainty. Each method is not designed to produce a definitive measure of safety, but should be viewed as an aid in the process of controlling or managing safety. Crucial to all design methods is the idea of a design parameter. However, in certain instances it is often not clear whether a design parameter should be an upper or lower bound on its possible value. A proposed limit state design method for overcoming this problem is outlined, based on putting bounds on parameters. An example of a reinforced concrete cantilever retaining wall is used to demonstrate its advantages over current methods. The proposed method offers a more rational approach to the design of retaining structures. 相似文献
555.
常用硅酸盐水泥护壁堵漏实践与探讨 总被引:1,自引:0,他引:1
水泥浆护壁堵漏是钻探施工对付复杂地层的有效方法之一。常用硅酸盐水泥通过外加剂改性可以获得与多种特种水泥同性能的水泥浆液。因而合理使用外加剂可以使常用普通水泥在现场处理复杂地层时代替特种水泥,取得良好的技术、经济效益。 相似文献
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随着国家重大构筑物的不断建设实施,考虑土体具有较高的动力易损性和致灾特性,工程构筑物的工程地质灾害和岩土工程动力致灾特性研究需要愈显迫切。通过对当前土动力学与岩土地震工程方面研究进展进行归纳总结,着重从土的动力强度、土的动本构关系、砂土的振动液化、铁路路基中的动应力、边坡地震永久变形和稳定性、挡土墙上的地震土压力等六个方面进行叙述,对其中涉及的各种研究方法进行比较和论述,最后提出了土动力学有待进一步深入研究的若干问题和未来发展方向,以期基于土动力学的发展而提升构筑物的抗震设防水平。 相似文献
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《Geomechanics and Geoengineering》2013,8(3):187-197
This paper presents the reliability analysis of reinforced retaining wall using finite element method. Response surface approach is used to approximate the performance function and a first-order reliability method (FORM) is used to evaluate the reliability index. In the analysis, displacement response of the reinforced retaining wall is considered as performance function and the corresponding reliability index is evaluated with the aid of a spreadsheet. Uncertainties associated with the soil and reinforcement properties are explicitly taken into account in the analysis. A parametric sensitivity analysis has been performed to bring out the effect of important uncertain parameters by evaluating the sensitivity of the reliability index with respect to each of the uncertain parameters. Results of the response surface method coupled with finite element analysis show the ease and successful implementation of the reliability analysis procedure for the reinforced retaining walls. 相似文献