扭应力

Two series of drained tests with fixed principal stress axes and cyclic rotation of principal stress axes were conducted with a hollow cylinder apparatus at Hong Kong University of Science and Technology.

采用香港科技大学的空心圆柱扭剪仪进行了应力主轴固定单调剪切和应力主轴循环旋转两种不同路径的排水试验。

The apparatus for static and dynamic universal triaxial and torsional shear soil testing is employed to perform stress-controlled cyclic coupled vertical and torsional shear test by different cyclic stress paths. Through a series of tests on saturated clay, the dynamic deformation, stress-strain relationship and dynamic strength are systematically investigated under rotation of principal stress axes.

针对饱和黏土，利用土工静力－动力液压三轴－扭转多功能扭剪仪进行了均等固结下的耦合循环剪切试验，着重研究了不同循环应力路径对应力－应变关系和强度特性的影响。

METHODS: The endodontic instrument was assumed as a metal conical bar. The normal stress of bending loads and the shear stress of torsional loads were calculated with the knowledge of mechanics. The relations between stress and such parameters as angle and radius of canal curvature, radius of instrument, polar moment of inertia, and metal elastic modulus were analyzed. The criteria for yielding and fracture of the instrument were discussed.

将根管器械刃部假设截面为圆的金属细锥杆，利用材料力学及断裂力学的原理与方法，分别计算根管器械在弯、扭载荷下的应力分布，分析应力与根管弯曲角度、根管弯曲半径、器械直径、器械横截面极惯性距、金属弹性模量等参数的确切关系；探讨器械屈服、断裂失效的准则。

METHODS: The endodontic instrument was assumed as a metal conical bar, the normal stress of bending loads and the shear stress of torsional loads were calculated with the knowledge of mechanics , the relations between stress and such parameters as angle and radius of canal curvature, radius of instrument, polar moment of inertia, metal elastic modulus were analyzed, the criteria for yielding and fracture of the instrument were discussed .

将根管器械刃部假设为截面为圆的金属细锥杆，利用材料力学及断裂力学的原理与方法，分别计算根管器械在弯、扭载荷下的应力分布，分析应力与根管弯曲角度、根管弯曲半径、器械直径、器械横截面极惯性距、金属弹性模量等参数的确切关系；探讨器械屈服、断裂失效的准则。

Also, the conversion between counteracting force and deflection of the bridge is achieved. The study analyzes on the characteristics of the beams" stress and deformation and gets the beams" vertical fiexture stress and deflection, their rigidity rotation stress and lateral inner force caused by the beams distribution of load.

通过实测结果，得到了桥梁的支反力与挠度，箱梁桥的受力特点：包括纵向弯曲产生的竖向变位，畸变角及由畸变产生的隔板横向弯曲应力，纵向弯曲应力及箱形梁的剪力滞现象及影响因素，箱梁桥刚性转动效应和截面的歪扭情况，箱形梁在局部荷载作用的横向内力，桥面板的有效工作宽度，荷载的横向分配分析。

On strength computation,the finite element models of rotating mirror were established according to the real structure of the mirror,and the rotating three-faced beryllium mirror were analysed.Results display that the surface deformation magnitude of the mirror is approximately 0.334 6 μm,and the maximum stress is 0.204 GPa at 600 m/s of edge linear speeed.The regions of maximum stress are on the axial hole and symmetric to symmetrical planes of mirror body,and keep beelines to surfaces.On the modal analysis,the results show that the first and second modals of bending vibration exist around 3.4×105 r/min and 6.6×105 r/min,which appear binate and orthogonal respectively,and another modal belongs to the first torsional vibration that occurs by 5.13×105 r/min.

运用该方法得出转镜镜面变形量、内部应力分布和振动模态参量的定量数值：在边缘线速度600 m/s下，三面体铍转镜的最大变形量为约0.334 6 μm；最大应力0.204 GPa，位于轴孔附近并与镜面距离最短处；两个在互相垂直平面内的一阶弯曲振动模态发生在3.4×105 r/min附近，一阶扭振点位于5.13×105 r/min附近，两个二阶弯曲振动点位于6.6×105 r/min附近。

But the steel box girder is typical space thin-walled bars, because of bending-torsion coupling and steel curved box bridge distribution of stress is relatively more complicated even under dead load, so it is necessary to distribute emulation analysis to the real stress of curved box bridge.

但是钢箱梁是典型的空间薄壁杆件，由于弯一扭耦合作用，曲线钢箱梁即使在恒载作用下其应力的分布也比较复杂，因此有必要对曲线钢箱梁实际的应力分布进行仿真分析。

The stress in tower type of derrick is smaller than the other types of derricks under the combined action of compressive and torsional loads.

与仅受压载荷相比，井架承受压扭联合载荷时，弦杆应力稍有增加，而非弦杆应力有较大的增加。

Tz = 2Gk q 即 z = 2Gk q /T 40 Suppose the volume between membrane and the boundary plane is V, and we notice that 2 ∫∫ d x d y = M Then we have Thereby we have q qM V =∫∫ zdxdy =∫∫ dxdy = 2GTk 4GTk M 2 Gk = 2V q /T From τ zx =τ xz =, y z 2Gk τ zx /= y q / T τ z y =τ yz = x 41 Moreover, we get 设薄膜及其边界平面之间的体积为V,并注意到 2 ∫∫ d x d y = M 则有从而有由又可得 q qM V =∫∫ zdxdy =∫∫ dxdy = 2GTk 4GTk M 2 Gk = 2V q /T τ zx =τ xz =, y z 2Gk τ zx /= y q / T τ z y =τ yz = x 42 Adjust the pressure q of which the membrane is under, and make the rights of formulas,, equal to one, then we can gain some conclusions as follows:(1) The stress function of wringed pole equals to the uprightness angle of the membrane (2) The torsion M which wringed pole received equals to two times of the volume between the membrane and the boundary plane.

o b y a x 43 调整薄膜所受的压力q，使得，，三式等号的右边为1，则可得出如下结论：(1)扭杆的应力函数等于薄膜的垂度z。(2)扭杆所受的扭矩M等于该薄膜及其边界平面之间的体积的两倍。

According to the Miner damage cumulative the fatigue life of torsion bar is analyzed and predicted based on two equivalent stress amending means Goodman and Gerber, combined with vehicle's driving environment, allocated proportion of driving load cases and material characteristic curve of torsion bar. The computational results indicate that Goodman is more conservative than Gerber and the difference between the predicted results is about seven times.

依据Miner线性损伤累积理论，结合车辆行驶环境和行驶工况的分配比例和扭杆弹簧材料特性曲线，采用Goodman法和Gerber法2种等效应力修正方法，对扭杆弹簧的疲劳寿命进行分析和预测，其计算结果表明Goodman法比Gerber法保守，两者之间的预测结果相差约7倍。

I'm strongly against the death penalty — it's an eye for an eye.

我不赞成死刑——这是以牙还牙的报复行为。

And to get you the support you need, we're enlisting all elements of our national power: our diplomacy and development, our economic might and our moral suasion, so that you and the rest of our military do not bear the burden of our security alone.

并给你们所须的支援，我们正徵召国家所有各种的力量：我们的外交及发展，我们的经济力量与道德劝说，所以你们与其他军人不须要孤独地负起国家安全的责任。