查询词典 volumetric strain

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。

According to this model and a great deal of test data, constitutive models to describe volumetric strain and generalized deviator strain are also proposed in this paper.

在此基础上，结合大量试验数据，本文还提出了描述体变、广义偏应变的简化本构模型。

Based on the test results of sand, mechanics of internal parameters (plastic volumetric strain and plastic deviator strain) depending on stress path is explained. General equation expressing hardening parameter independent of stress path is proposed.

在分析砂土试验结果的基础上，揭示了基本硬化内参量(塑性体积应变、塑性剪应变)变化的应力路径相关性，提出了应力路径无关硬化参量的一般表达式。

Vesic's solutions to cavity expansion that include cylindrical cavity expansion and spherical cavity expansion are introduced. Then cylindrical cavity expansion theory is applied to study compaction effect of pile driving in saturated soil. Based on the results of conventional triaxial tests, a trilinear curve model is used to simulate stress-strain curve of strain-softening materials. Meanwhile, trilinear curves are also used to simulate curves of volumetric strain, minor principal strain and major principal strain. By using elasto-plastic theory, analytical solutions to cylindrical cavity expansion in strain-softening soil are presented. According to the mechanism of statically pressed pile driving, compaction effect of pile tip can be viewed as hemispheric cavity expansion. Therefore spherical cavity expansion theory is applied to obtain the solutions to stress, strain, displacement fields and final pressure. Resistance force of pile tip is calculated to estimate static pressure.

介绍了Vesic关于圆孔扩张问题的解答，其中包括柱形孔扩张问题和球形孔扩张问题，并应用柱形孔扩张理论分析了饱和软土中的沉桩挤土效应问题；在常规三轴试验成果的基础上，采用三折线模型模拟具有应变软化性质的岩土材料的应力应变关系曲线，分析了在应变软化土体中沉桩时桩周土的位移场、应力场和应变场的变化，得到了解析解答；分析了静压桩的沉桩机理，并利用球形孔扩张理论，视桩端处的挤土为半个球形孔的扩张，分析了桩端处土的位移场、应力场和应变场的变化，并根据最终扩张压力计算出沉桩时的桩端阻力，可作为压桩力的估算。

These tests show that: 1. suction decreases with the increase of the water saturation in the chalk; 2. stress variants proposed are available for describing the stress state of the unsaturated chalk; 3. preconsolidation pressure increases with suction, while the effects of suction on the compressibility coefficients λ and κ are not evident; 4. as usual unsaturated soils, the permeability to oil of chalk increases with the suction; 5. yield strength of the chalk behaves with volumetric strain hardening; 6. cohesive behaviour of the chalk is related to the stress level, and relation between time-dependent deformation and logt is linear; 7. cohesion of the chalk decreases with the increase of the suction, while the elastic stiffness and the cohesion coefficient increase; 8. strength and elastic modulus increase with the strain rate, while the strain at the peak strength decreases with the increase of the strain rate.

试验结果表明，白垩中的虹吸力随水饱和度的降低而提高；吸力、水饱和度和强度的变化过程均与时间有关；可用由理论分析得到的应力状态变量描述非饱和白垩的平衡状态；前期固结压力随吸力增加而提高，而压缩指数λ与κ则同吸力无关；应力大于前期固结压力时，粘性变形与时间的对数关系曲线呈线性关系，其大小和增长速率均随吸力减小而增大，可视为白垩弹性刚度降低和粘性系数增大的结果；前期固结压力和变形模量随着应变速率的提高而提高，压缩指数κ和λ则随应变速率的提高而减小；应变速率较低时，粘性和吸力对前期固结压力及压缩指数的影响较小；白垩中油的渗透性随着吸力增加而提高；白垩在屈服阶段具有明显的体积应变硬化特性。

Taking a Mohr-Coulomb type of soil as example, the relationship between plastic shear strain and plastic volumetric strain is deduced, and the reason behind volumetric locking is revealed.

以摩尔－库仑模型为例，推导了塑性剪切应变和塑性体积应变的关系，揭示闭锁产生的原因。

The bulk modulus describes volumetric elasticity, or the tendency of an object's volume to deform when under pressure; it is defined as volumetric stress over volumetric strain, and is the inverse of compressibility.

体积模量，描述了测定体积的弹性，或者说一个物料在压力作用下的体积相对于变形的程度；它被定义为体积应应变下的体积应力，且是体积柔量的倒数。

The developments of four strain components and the volumetric strain with number of cycles, the relationship between shear stress and shear strain and the effects of deviatoric stress and effective mean normal stress were studied.

着重分析了4个应变分量及体应变随应力主轴循环旋转周数的变化关系、剪应力剪应变关系以及所施加的剪应力水平和有效球应力在应力主轴循环旋转过程中对砂土变形特性的影响。

The fundamental feature of this procedure is the modified relationship of stress and strain by residual shear strain potential and residual volumetric strain potential in dynamic time-history analysis. In the meanwhile, the effect of the residual dynamic pore water pressure on the maximum shear modulus is considered.

该方法在动力时程分析中重点考虑了逐渐累积的残余剪应变和残余体应变对应力应变关系的软化效应，同时考虑了各时段残余振动孔压引起的最大动剪切模量的衰减效应。

According to triaxial consolidation curve of saturated clay, the relation between the volumetric strain and the average effective stress and the relation between the volumetric strain and the vertical strain at a particular instant of time were derived.

2.2。根据软粘土的三轴排水固结试验曲线，建立了土中一点在任意时刻的体积应变与平均有效应力之间的关系式以及竖向应变与体积应变之间的关系式

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。