土体

The main factors affecting the soil-structure interface behaviors were found experimentally and theoretically, including: 1 the thickness of the interface that is five to six times the average grain size of the soil; 2 the aeolotropy of interface, which is responsible for anisotropic response of the stress-strain response of the interface; 3 two physical states, including crashing and compression of the soil near the structure surface, which govern the stress-strain response of the interface strongly; 4 two shear deformation components due to sliding and constraint of the structure surface relative to the soil respectively, which forms the deformation of the interface; 5 the volumetric strain due to dilatancy, which is found to be composed of a reversible dilatancy component and an irreversible dilatancy component. 4. A unified constitutive model of the interface, based on new elasto-plasticity damage theory, was developed. It was confirmed to be effective for the conditions considering monotonic and cyclic shearing, coupling effect of shear and volumetric strains, evolution of physical state, micro-structure aeolotropy of the soil and the resulting aeolotropy of the interface as well as the three normal boundary conditions stated above. 5. 2D and 3D finite element formulations of the present model were derived and incorporated into the FEM codes. They were applied to the evaluation of practical engineering problems with different typical interfaces between soil and structure. The new model was shown to be reasonable and effective.

确定了粗粒土与结构接触面厚度约为5～6倍的平均粒径，首次揭示了接触面的细观结构异向性以及由此所引起的宏观剪切异向性，发现了在单调和往返剪切荷载作用下土颗粒破碎和剪切压密两种物态变化机制共同支配着接触面力学性质的变化，通过细观分析证实了接触面的变形可分解为一般同时发生的土与结构交界面上的滑移变形以及结构面位移约束范围之内土体本身的剪切变形两部分，观测到接触面受剪时表现出明显的相对法向位移，并可分解为可逆性和不可逆性两个分量；(4)建立了第一个能够统一地描述单调与往返剪切特性、剪应变与体应变耦合特性、细观结构和宏观剪切异向性以及土颗粒破碎等物态变化特性的土与结构接触面弹塑性损伤本构数学模型，并采用多种法向边界条件复杂加载路径的试验成果验证了新模型的合理性和有效性；(5)提出了新模型的二、三维有限元格式并结合实际边值问题进行了应用计算分析，比较了不同接触面本构模型对计算结果的影响，证实了新模型及其有限元格式不仅能够合理地描述土与结构接触面的主要力学特性，还能够较好地反映土体与结构物在接触面处的滑移、脱开等不连续现象。

The paper studies the rational back aggraclation width of yellow river dike with reliable theory,researches and formulates the finite element reliability program of Monte-carlo filtration for calculate the failure probability of filtration stability for soil body of different distance from slope base of yellow river dike under design flood level,thus determines the rational back aggradation width.

利用可靠性理论对黄河堤防淤背设计的合理宽度问题进行了系统的分析研究，充分考虑了黄河堤防土体参数的随机变异性，研制了蒙特卡洛渗流有限元可靠度程序，用来计算在设计洪水位下距黄河堤防背河坡脚不同距离的地层土体渗流稳定破坏概率，从而确定合理的淤背宽度。

In the term of unloading and opposite side loading, let the stress-strain curve have the same form of skeleton curve, the curve uses the last unloading point as its starting point, and uses soil's ultimate stress level as its asymptote. Then the hysteretic curve is constructed.

在卸载和反向加载时，采用与骨架曲线相同的函数形式，并以前一次卸载开始点作为起点，以土体的极限应力水平作为渐近线，构造出土体动力本构模型的滞回曲线。

The influences of the circumambience soil on the vibration of dynamic equipment foundation are simulated, which reveal that the circumambience soil has a remarkable effect on the foundation vibration and almost has no effect on the vibration of isolation platform.

模拟了动力设备基础周围土体对振动的影响，计算结果表明，动力设备基础周围土体对基础的振动影响较大，但对隔振台座的振动几乎没有影响。

The design concept and feasibility condition of the scheme is introduced, and the pressure on the claybank is discussed, A practical design method using reduced "m" value for structure computation and Rankine passive earth pressure for claybank calculation is developed, which is proved to be feasible and safe by practice.

着重介绍方案的设计思路、成立条件，并对作用在平衡土体上的土压力大小进行讨论，并提出了按折减m值进行支护结构计算、按朗肯被动土压力进行平衡土体验算的实用设计方法。工程实践表明，采用中心岛法具有突出的综合效益，所提设计方法安全可行。

The achievement that soil ultimate bear capacity heightened under pile caps due to barrier effect of piles gained from model test, and soil move around piles acquired from numerical simulation, its not only verified hypothesis of composite pile foundation nonlinear design theory, but have important reference value to the study of design theory and design method of composite pile foundation, which help to go deep into study of promote pile-soil-pile caps nonlinear interaction theory and composite pile foundation nonlinear design theory.

由模型试验得到的桩的遮拦作用对承台下土体极限承载力提高和数值模拟得到的土体绕桩流动等成果，不仅验证了

It is shown that the friction force and bulkhead thrust are the main factors of shield thrust setting, while the friction between the cutterhead and soil is the main factors of cutterhead torque setting. Friction force between shield and soil would make front soil of shield upheave, and subsidence of surface soil is induced by ground loss when the friction force between the cutterhead and soil results in the surface settlement asymmetrical distribution.

通过计算发现，盾构施工中盾壳摩擦和正面推力是盾构推力设置的主要因素，而刀盘与土体摩擦是刀盘扭矩设置的主要因素，盾构前方土体隆起主要由盾壳摩擦引起，刀盘摩擦作用主要引起地表沉降的非对称分布，地表沉降主要由盾尾空隙产生。

After determining the control equation and defined problems for infiltration, redistribution and evaporation, implicit finite difference method was used for ponded infiltration, semi-infinite soil redistribution and semi-infinite evaporation. The calculated results agreed well with measured data.

9在确定了入渗、再分布及蒸发的控制方程及定解问题基础上，采用隐式差分格式对垂直一维积水入渗、半无限土体再分布及半无限土体蒸发进行了数值模拟，与计算结果对比表明，计算值与实测值比较符合。

In order to deep holding the engineering characteristic of the coarse-grained soil, this paper researched object that is the coarse-grained soil of the diametre from 0.1mm to 20mm that was often applied in the dam body filter structure, using the experiment method, carrying out the experiment the research of the coarse-grained soil permeability characteristic.

粗粒土在水力作用下，是一种结构极不稳定的土体，在渗流作用下极易发生渗透变形，容易引起坝体的渗透变形破坏。从渗透系数的变化上分析，其渗透变形过程是一个连续的过程，土体的破坏形式大都属于管涌破坏，破坏坡降较小，一般破坏坡降都小于2.5，有的甚至小于1.0。

In spite of the granular nature, soil has traditionally been modeled as a continuum. This continuum mechanics cannot get the precise solution while soil\'s nonlinear, discontinuous, large deformation, and strain localization behavior are considered. The discrete element method is based on discontinuum theory, and is pioneered by Cundall.

土是由多相介质组成的离散颗粒集合体，尽管研究者早已在土的散粒状属性上达成共识，但关于土体力学性质的研究还经常沿用连续介质力学方法，这种基于连续体小变形假设的方法在求解实际土体非线性、非连续、大变形、应变局部化问题时往往无法得到精确解答。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失