压应力

In this paper, the analytical expressions of seismic input for homogeneous elastic half-space are first derived in oblique incidence of plane SV-wave, and then a finite element model for a real hydropower cavern group composed of main powerhouse- transformer chamber- tailrace surge tank cavern is created. Characteristics of seismic responses such as displacement, acceleration and stress are studied in detail at different incidence angles and some results are compared with those given by the literature.

本文首先推导了平面SV波斜入射下均质弹性半无限空间的地震动输入表达式，然后建立了某水电站主厂房室-主变室-尾水调压室等构成的地下洞室群有限元模型，详细研究了不同入射角度下各洞室的位移、加速度、动应力等地震反应特点，并与文献进行了对比。

The critical pressure difference is 0.767MPa when the high and low pressure zones distribute along the direction of maximum principal stress.

高、低压力区沿最大水平主应力方向分布时，发生套管变形的临界压差为0.767MPa。

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。

The stress field,especially the orientation of horizontal principal stress in vertically-fractured gas well,determines the azimuth of refracture creation and refracture propagation.

根据弹性力学理论和岩石破裂准则，裂缝总是沿着垂直于最小水平应力方向起裂，因此，重复压裂井中的应力场分布决定了重压新裂缝的启裂和延伸。

Moreover, the sensitivity and reversibility of cement-matrix composites are affected by both the stress and moisture content.

而且，各水泥基复合材料压敏性的灵敏度和可逆性与所受应力大小和含水量密切相关。

To meet therequirements of large-scale of oil refining equipments, rigorousness oftechnical conditions and complexity of structures, special pipe fittings suchas Pants tees and Y-tees are used for the purpose of reducing fall ofpressure and temperature. However high stress concentration is alwaysfound there, cause underlying safety problems.

随着炼油装置的大型化和工艺条件要求的提高以及结构的复杂化，为了减小压降和温度降，采用裤型三通、Y 型三通一些特殊的管件形式，在 Y 型三通、裤型三通的局部往往会有应力高度集中，给设备安全造成隐患。

In the paper, the present state of ultra-fine-grained materials, severe plastic deformation and Asymmetrical-ARB are introduced in detail; the craft to fabricate ultra-fine-grained copper using Asymmetrical -ARB is studied fully; the problem of combination of interface is settled; the affect of homogenizing annealing、 annealing and rolling method on mechanical properties of materials prepared by Asymmetrical-ARB is discussed and analyzed when control parameters of rolling mill such as the press—ratio、 the asynchronous rate、 rolling—speed are fixed, and a kind of craft that meets to requirement of experiment is made out.

本文对超细晶、大塑性变形技术、异步轧制目前国内外研究进行了详细的介绍；对异步叠轧方法制备超细晶铜工艺做了较为细致的研究：解决界面复合问题；在压下率、异步比、轧制速度等轧机控制参数固定条件下，探讨了均匀化退火工艺、去应力退火工艺和轧制方式对异步叠轧材料力学性能的影响，并进行了分析，制定出符合实验要求的轧制工艺。

LPG ; Pressure of saturated vapour ; Low-temperature stress ; mount of stockpile.

液化石油气；饱和蒸气压；低温低应力；储存量

Variation of striper force and clearance between punch and die plate with respect to shear plane and die stress were analyzed .

分析了不同压边力和凸凹模间隙对精冲断面质量和模具应力的影响关系。

According to the results of triaxial compression test, the relationship of cement soil mixed with or without glass fiber concerning stress and strain in different ages and confining pressures was analyzed. Meanwhile, some parameters of cement soil mixed with glass fiber, such as shearing strength parameter, modulus of deformation and relationship between compression strength and deformation modulus were obtained.

根据玻璃纤维-水泥土的三轴压缩试验结果，分析了其在不同围压与龄期下的应力-应变关系，并得到玻璃纤维-水泥土的剪切强度参数、变形模量E50及变形模量与抗压强度qu的关系。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。