剪下

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 instructive conclusion was: 1 under the vertical loading, the shear-lag effect was produced badly, more severer under concentrated loading than under uniform loading .2 the longitudinal bending deformation of the beam flange was true of the imitating plane assumption of deformation . 3 the width length ratio was confirmed as the first factor working on the shear-lag effect among all the geometric parameters;4 the shear-lag coefficient of simple-supported box-girder was severer than the continuous box-girder, the shear-lag effect in the inner supported section of continuous beam was much more severer, we need paying more attention for it in designing. 5 the non-liner characteristics of material deformation have littlie influence on shear-lag effect in BGCW. 6 the experiential calculating formulation and calculating diagram for the effective flange width was raised with the only factor of the width-span ratio., but the primary location of axis of bending moments should not be changed while calculating the inertial moment .

研究认为：1室内模型试验和空间有限元分析结果均表明波形钢腹板组合箱梁在竖向荷载作用下，翼板出现了典型的纵向应力剪滞效应。2在竖向荷载作用下，截面高度上各点纵向正应变分布认为可符合"拟平截面假定"，以此作为波形钢腹板组合箱梁抗弯计算的基本假定。3箱梁宽跨比是影响波形钢腹板组合箱梁翼板剪滞效应的主要因素。4连续波形钢腹板组合箱梁的翼板剪滞系数大于简支梁，且连续箱梁内支点截面翼板剪滞效应相当严重，对此需十分重视。5当混凝土翼板受力由弹性阶段进入弹塑性阶段时，材料的非线性特性对翼板的剪滞效应影响甚微。6提出了根据组合箱梁的宽跨比参数来计算翼板有效宽度比的经验公式和计算图表，但箱梁截面抗弯惯性矩的计算不应改变原先的截面中和轴位置。

Five main phenomena were found, firstly, the high plasticity clay could well suitable to large deformation, and had strain-hardening behavior obviously, as well as, the little dilatancy; secondly, there was no correlation between stress paths and shear strength but the stress-strain relations were influenced by stress paths; thirdly, the little stress increment ratio, the higher increase speeding of shear stress and breaking strength under the condition of same initial normal stress; the fourth, the relations between normal strain and normal stress in simple shear test was consistent with which in the single-direction compression test, if there was no dilatancy; the last, the curve of relation between stress ratio and shear strain could be well simulated by hyperbola.

试验结果表明，高塑性粘土能够较好地适应大变形，接触面剪应力与切向应变关系呈剪切硬化型曲线，法向剪胀不明显；接触面剪切强度与应力路径无关，应力应变关系与应力路径密切相关；初始法向应力一定，应力增量比越小，剪应力增长越快，对应的破坏剪应力也越高；无剪胀发生情况下，法向应变与法向应力关系曲线与单向压缩试验具有一致性；应力比与切向应变呈良好的双曲线关系。

The rheological character of a polymer often appears as shear-thinning. Most polymers behaviour in a solution can be explained by the polymer chain or hard sphere theory. Other than that, shear-thickening polymer solution also exists. Its behavior can be explained by dilatant theory, which suggests that the shear-thickening of the solution is due to the swelling of the polymer particles. This phenomenon often occurs in suspension or emulsion. Solution exhibits a mixed behavior can also be found whose behavior is such that shear-thinning occurs under low shear force and shear-thickening occurs under high shear force. Under this circumstance, the viscosity versus shear force graph exhibits a spoon shaped curve. The rheological study can be applied to the dispersion of paint which can predict the dispersion effect of various polymer materials in solution.

中文摘要一般高分子聚合物溶液的流变行为多半呈现剪稀(shear-thinning)的现象，而大部分的高分子在溶液中的行为是以分子链或是硬球观点来解释，另外也有剪稠(shear-thickening)现象的高分子溶液，其流变行为则是以膨胀体观点来解释，即在高剪切力下，由於高分子团体积变大而使溶液黏度升高，这在悬伏液、乳液等常见；但也有在低剪切力下，溶液具有剪稀的行为，而在高剪切力下却成现剪稠的行为，在黏度对剪切力作图时，会呈现出一个勾形曲线的图形；流变行为的探讨可应用在涂布材料的分散技术上，以推测不同的高分子溶液对分散效果的影响。

The shear modulus or modulus of rigidity describes an object's tendency to shear (the deformation of shape at constant volume) when acted upon by opposing forces; it is defined as shear stress over shear strain.

剪切模量或刚度模量，描述了一个物体在反力作用下的受剪切程度；它被定义为剪切应变下的剪切应力。

The plastic deformation induced due to cyclic rotation of principal stress axes alone can be in the same magnitude as that due to shear with fixed principal stress axes. 2 The volumetric strain due to shearing of cyclic rotation of principal stress axes is found to be composed of a reversible dilatancy component and an irreversible dilatancy component. The former is characterized by its reversibility and is independent of past shear history, the latter by its irreversibility increases with the increase of cycle number yet its increase rate decreases with its accumulation. 3 The obvious non-coaxiality between directions of the principal stresses and principal strain increments is found and its degree depends largely on the change of shear stress component. 4 The intermediate principal stress has considerable effects on the deformation behavior of sands in the condition of cyclic rotation of principal stress axes. The accumulation rate of the irreversible dilatancy component increases with the increase of the intermediate principal stress parameter.

具有初始各向异性的砂土在纯应力主轴循环旋转排水条件下的主要变形规律为：①纯应力主轴循环旋转可产生与应力主轴固定单调剪切处于同一数量级的塑性变形；②纯应力主轴循环旋转引起的剪切体变包含可逆性剪切体变分量和不可逆性剪切体变分量两部分，其中可逆性剪切体变分量在一周内可完全恢复，基本与应力历史无关；不可逆性剪切体变分量随循环周数的增加呈单调增加，且增加速率随其自身累积值的增大呈减小趋势；③应变增量主轴与应力主轴之间的非共轴现象显著，且在一周内具有分段性；④中主应力对应力主轴循环旋转条件下砂土的变形特性有重要影响，不可逆性剪切体变分量的累积速率随中主应力系数的增加而增加。

By the numerical analysis of the ultimate bearing capacity of two- and three-dimensional footing under combined loading mode, the results show that the effect of alteration of underground water lever on bearing capacity of three-dimensional foundation is more than on that of two-dimensional foundation, the effect of soil gravity on bearing capacity of three-dimensional foundation is more than that of two-dimensional foundation. At the same time, the numerical calculation process of ABAQUS indicates that whether the geostatic stress is balanced or not has great effect on the numerical convergence. In view of the effect extent of dilation angle of soil on the ultimate bearing capacity and the failure pattern of foundation, the condition of two-dimensional plane strain is higher than that of the three-dimensional foundation.

复合加载模式下，通过对三维矩形基础和二维条形基础进行数值分析，结果表明：黏性土地基中地下水位的变化，对三维矩形基础极限承载力的影响程度高于对二维条形基础的影响；在求解地基极限承载力的过程中，土体重度对三维矩形基础的影响明显高于对二维条形基础的影响，同时ABAQUS数值计算过程表明，地基土体地应力能否合理平衡，对数值求解过程中是否收敛有很大的影响；就土体剪胀角对地基极限承载力的影响程度而言，二维平面应变情况下土体剪胀角对极限承载力的影响比三维情况下的影响更明显，即土体剪胀角对条形基础极限承载力的影响高于三维矩形基础。

As the results, the ultra-thin films of 500SN and hexadecane exhibited nonlinear shearing response, which was different from that of the Newtonian fluids in their bulk state.

结果表明：在超薄膜润滑条件下，5 0 0 SN和十六烷均表现出明显的非牛顿剪切响应，即剪切稀释现象；摩擦力幅值随剪切速度的增大急剧上升到最大值，然后下降至某一固定值附近并产生波动；剪切挤压下的临界膜厚小于静态挤压的临界膜厚，剪切运动对吸附层有序结构产生破坏作用

In this way,after the viscosity or apparent viscosity of virgin crude,corresponding unsheared PPD-beneficiated crude and the sheared PPD-beneficiated crude at a certain temperature are determined,the parameters in the model can be calculated.

按照此方法，只须测定一定温度下空白原油的粘度或表观粘度、未剪切时加剂原油的粘度或表观粘度，及在某一个剪切温度下及某一个粘性流动熵产条件下原油的粘度或表观粘度，即可近似确定该数学模型中的参数，从而预测在不同温度时剪切后的原油在该温度下的粘度或表观粘度。

By way of parenthesis, In One-Point Input Method the relation is studied between the response and the correlative coefficient of horizontal and vertical earthquake wave.

提出了基于动剪应力极值的土体损伤值计算方法。以往计算土体在不规则的动剪应力作用下的损伤值根据的是动剪应力的峰值，在时域内多点输入分析中，由于差动力的的存在，使得时程后段动剪应力不穿零而在一侧做幅度不大的波动，基于峰值的损伤值计算特别过高地估计了这段剪应力的破坏作用，过高的程度还随延时增加而增加。

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