孔隙水压力作用下抗滑桩加固边坡的极限分析上限解

用对数螺旋线形的破坏机制和极限分析上限法,对抗滑桩加固边坡的稳定性进行了研究。基于构建的抗滑桩加固边坡的破坏机制,推导了抗滑桩加固边坡的内、外功率表达式。通过切线法将土体的非线性破坏准则引入到极限分析方法中,并结合强度折减法建立了抗滑桩加固边坡的安全系数隐式表达式。用最优化方法,计算得到了孔隙水压力作用下的边坡安全系数。在此基础上,分析了抗滑桩加固位置、孔隙水压力以及非线性抗剪强度等参数对抗滑桩加固边坡安全系数的影响。结果表明:土体抗剪强度对抗滑桩最佳布设位置的影响较小;非线性条件下,边坡安全系数随着初始黏聚力的增大而增大,随着抗拉强度和非线性系数的增大而减小。     

排桩加固支护边坡作用机理的有限元分析

目的为了解决滑坡推力较大时,单排抗滑桩加固不能保证边坡的安全可靠,确定一种更加安全的边坡支护措施.方法采用强度折减的有限元法对某水电站厂房后边坡进行模拟,将得到的安全系数与极限平衡法所得安全系数进行对比,然后分别对采用单排抗滑桩和双排抗滑桩加固的边坡进行三维数值分析.结果计算表明,强度折减的有限元法分析此边坡是可行的,采用双排抗滑桩加固边坡比采用单排抗滑桩作用更加明显,在桩身位移,桩身弯矩最大值以及桩身的剪力方面,双排抗滑桩都不同程度的小于单排抗滑桩.结论在保证边坡抗滑桩加固工程的安全可靠性的前提下,可以使用单排桩加固的支护措施,当边坡推力较大时,需采用双排抗滑桩,可以大大降低工程成本,提高经济效益.     

抗滑桩加固边坡稳定性分析

以大型通用有限元分析软件PLAXIS作为平台,通过改变抗滑桩支护参数桩长和桩位来研究抗滑桩加固边坡的效果.研究结果表明:当抗滑桩桩长较小时,桩位设置在边坡的中下部对边坡稳定性更有利,当抗滑桩桩长较长时,桩位设置在边坡的中部对边坡稳定性更有利;抗滑桩桩长对边坡加固后的稳定性影响程度与桩位的设置有关系,抗滑桩位于坡顶、坡脚时,桩长对边坡的稳定性影响不明显,抗滑桩位于边坡中部时,桩长对边坡的稳定性影响较明显;抗滑桩位于边坡中部时,随着桩长的增大,最初边坡安全系数不断增大,当桩长达到一定长度时,安全系数不再变化.     

抗滑桩加固边坡稳定性及影响因素的有限元分析

通过Fortran95语言编制边坡在抗滑桩加固情况下的稳定性程序(FPS),并与商业软件FLAC3D的计算结果进行对比,以验证程序的正确性及优越性;然后,通过抗滑桩支护参数对边坡稳定性的影响进行分析.研究结果表明:(1)当桩长较小时,抗滑桩设置在边坡中下部对稳定性最有利,当桩长较大时,抗滑桩设置在边坡中间对稳定性最有利;(2)桩长对于边坡安全系数的影响程度与抗滑桩布置的位置有关,当抗滑桩位于坡顶或者坡脚时,桩长的变化对于安全系数的影响很小;而抗滑桩位于边坡坡面中央时,在桩的长度达到临界桩长之前,边坡的安全系数与桩长呈显著的线性关系;(3)随着桩长的不断增大,潜在滑动面逐渐向边坡内部移动,破坏模式由浅层滑动变为深层滑动,安全系数也不断增大;但当桩长达到一定程度后,边坡的临界滑动面转移到临坡面位置.     

抗滑桩加固路基边坡研究进展及应用

对抗滑桩加固路基边坡的国内外现状进行了概述。提出了抗滑桩在设计计算方面存在的一些问题,如抗滑桩的受力状态与桥桩受力状态的区别,滑坡推力与桩前滑体抗力的分布规律,锚固段长度的确定等,以此为抗滑桩在加固路基边坡方面的设计计算提供有用的参考。     

高速公路改扩建工程边坡抗滑桩加固效果数值分析

为了分析改扩建工程中使用抗滑桩对边坡加固治理时的支护稳定性,基于FLAC3D软件对某改扩建边坡利用抗滑桩加固效果进行数值模拟,得到边坡的应力应变云图、桩身前后岩体压力及桩自身内力的分布规律。研究结果表明:抗滑桩的阻挡作用使桩周岩体局部应力增加,抗滑桩处的剪应变增量增大;抗滑桩前、后的岩土压力呈三角形分布,边坡滑裂面以下岩土压力分布复杂,可近似认为属于梯形或矩形分布;抗滑桩桩体在滑裂面位置处的剪力和弯矩最大。     

抗滑桩加固边坡稳定性分析及其优化

利用数值方法分析抗滑桩在边坡中的加固效果,探讨在抗滑桩-边坡体系中,设桩位置、桩长、桩体弹性模量等因素对边坡稳定系数、临界滑移面以及桩体的内力、变位响应的影响。研究结果表明:抗滑桩的最优设桩位置受桩长的影响较大,若桩长较短,则布设抗滑桩于边坡中部具有最好的加固效果,若桩长较长,则在边坡中上部设桩对边坡稳定性更有利;随着抗滑桩位置向坡顶移动,桩身内力、桩体挠度先增大后减小,并在边坡中下部同一位置达到最大值,同时,在移动过程中,边坡临界滑动面逐渐往临坡面移动,当移动到边坡中上部时,滑移面位置发生突变;随着抗滑桩桩长的增大,桩身弯矩随之增大,而桩体剪力变化很小,在抗滑桩加固边坡工程中,存在一有效嵌固深度Heed,在Heed以内,边坡稳定系数和桩长的关系符合抛物线特征,同时,Heed受设桩位置的影响;提高抗滑桩弹性模量可小幅度减小桩体挠度,但并不能提高边坡稳定系数,故在抗滑桩工程设计时,应综合考虑,合理确定桩身弹性模量。     

填土边坡稳定性评价及其抗滑桩设计方案的探讨

在介绍一中型填土边坡破坏的基础上，对其稳定性进行了分析评价，并应用抗滑桩的极限承载理论和绕流阻力理论探讨了该边坡的支护设计，对该土质边坡，提出了一套具有一定参考价值和针对性的抗滑桩设计方案。     

基于加固边坡的可靠性分析设计抗滑桩锚固深度

为了对抗滑桩锚固深度进行合理的设计,建立位移迭代有限元模型模拟桩-土间的相互作用,基于强度折减的位移迭代有限元法对边坡抗滑桩加固工程进行可靠性分析,把计算参数视为随机变量考虑参数变异性对抗滑桩锚固深度及边坡加固工程可靠性的影响。可靠指标的选取应考虑边坡工程等级,以目标可靠度为控制指标去指导抗滑桩锚固深度的设计。工程算例表明采用可靠性方法设计抗滑桩锚固深度是合理的,具有一定的工程应用价值。     

钢筋混凝土抗滑桩在露天矿边坡治理中的应用

为了解决宝日希勒露天煤矿采场边坡失稳的问题,论述了采用抗滑桩来进行边坡治理的途径.通过对地质条件及现场情况的分析,将采用大型钢筋混凝土抗滑桩加固边坡.计算结果表明:该方法技术上可行,经济上合理,是解决露天矿边坡失稳的理想措施之一.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that