应力

The paper analyzed the residual stress in the machine frame of drying part of the high speed paper machine caused by welding, discussed the effect of welding parameters on the residual stress and compared the mechanisms and efficiencies of eliminating the weld stress by heat treatment and aged-vibrating processes.

摘 要：对高速纸机干燥部机架焊接所产生的残余应力进行了分析，指出了焊接工艺参数对残余应力的影响；分析比较了热处理和振动时效两种工艺方法消除焊接残余应力的机理和效果。

The research results show as follows: if the gas pressure is fixed, the seepage velocity of briquets drops at first and rises later with increasing axial stress, and increases after peak stress.

研究结果表明：恒定瓦斯压力时，在某一围压下，峰前渗流速度随轴向应力先减小后缓慢增大，到达峰值应力后，随轴向应力的减小而增大。

Combining the actual rockburst status after excavation, based on the previous research data in the earlier stage, the character of the tectonic stress in Cangling Tunnel is studied. Finite element method is adopted to simulate the site excavation steps. At the same time, the tectonic stress is changed on the boundary of the model to simulate the actual rockburst areas; and the most proximal area's value is adopted to decide the section tectonic stress. Then, other sections' values are revised.

从苍岭隧道的构造应力场特征入手，结合现场开挖后岩爆实际发生状况，在前期研究资料的基础上，利用有限元计算分析，模拟现场实际施工步骤的同时不断改变模型边界上的构造应力来拟合实际岩爆区，以最接近实际破坏范围的计算结果界定区段构造应力值，据此对隧道各区段的构造应力进行修正。

The results show that space finite analysis results are close to test ones, bottom chords suffer axial force and large in-plane bending, and the max stress is nearby each middle internode. The max stress of node crossbeams occurs in No.2 bottom flange, and that of internode crossbeams happens in ones lying in the middle of every internode. The concrete slab is in tension at the longitudinal direction, and also suffers bent at vertical loads. The degree of completely-composite model taking part in the combined actions is about 55%, while that of semi-composite model is 42%-43%. The combination of concrete slab and bottom chord increases the degree of floor system taking part in the combined actions, lightens the burden of bottom chord, and reduces out-of-plane bending of node crossbeams especially the ones near bridgehead. Stress and displacement of main truss can be evaluated by a equivalent plane rigid frame in preliminary design, and effective stiffness of bottom chords are composed of original ones and concrete slab, and the concentrated load from deck can be translated into uniform load.

研究结果表明：空间有限元分析结果与试验结果较吻合；下弦杆受到轴向拉力和较大的面内弯矩作用，各节间最大应力出现在节间中点附近；节点横梁最大应力发生在横梁2的下翼缘，节间横梁最大应力发生在位于端节间中部的小横梁上；混凝土板顺桥向整体受拉，并在竖向集中荷载作用下产生弯曲变形；全结合模型大部分节间内的桥面板参与主桁共同作用的程度为55%左右，半结合模型桥面板的参与程度为42%~43%；桥面板与下弦杆结合能够增加桥面板的参与程度，减轻下弦杆荷载，减少节点横梁尤其是靠近桥头横梁的面外弯曲；对桥梁进行初步设计时，主桁杆件的位移与内力可按照1个等效的平面刚架计算，下弦杆的等效刚度由原下弦杆截面和混凝土桥面板截面组合而成，桥面荷载可转化为均布荷载施加。

In the core area of the node crossed by two diagrid columns, the node section area is far smaller than the sum of two columns' section areas.

摘要］国外某工程，外部网筒由圆柱斜向交叉与环梁编织而成，外网筒柱节点核心面积相比柱截面面积大幅减小，承载力不足，经有限元分析，汇交节点应力状态复杂，阴角区存在明显的应力集中，通过弹性、弹塑性有限元分析，找出了应力集中的原因，进而有针对性地提出了采用钢板凳进行加强的措施，取得了较好的效果。

The results show that most of stress drops Δσ in the volcano areas are between 0.2-2MPa, averaging 0.95MPa. Ambient str esses τ0 are between 0.7-3MPa, averaging 2.2MPa, an area with low stress.

结果给出，火山地区的应力降Δσ多数在0.2～2.0MPa 之间，平均为0.95MPa；环境应力τ0值在0.7 ～3.0MPa 之间，平均为2.2MPa，属于低应力地区。

The residual stress can also change the transition energy of excitons.

薄膜应力是影响ZnO薄膜紫外荧光发射性能的重要因素，较小的残余应力对ZnO薄膜的紫外荧光发射是有利的，残余应力的存在可以改变ZnO薄膜紫外荧光发射能量。

Expansion loops are used to manage expansion and to assure that the piping system is flexible enough to accommodate the expansion without pipe stresses exceeding the allowable stress and stress range prescribed by the Code.

膨胀弯被用于控制膨胀，和用来确保管系足够的柔性，从而使得其管系的膨胀不存在管道应力超过规范上要求的许用应力和应力范围。

Analyzing the stress distribution of pelvis and units displacement when transient stress was loaded,can provide internal fixation point for treatment of pelvic fracture and further understanding the stress distribution of pelvis.

分析冲击载荷作用下骨盆各部位应力分布以及骨盆各个单元在应力作用下的位移变化，有助于临床上进行骨盆损伤内固定力点的选择以及进一步明确骨盆内在应力值分布。

The analysis shows that, the maximum stress change appears in the heat affected zone of the flange's center and it has main influence on surface crack of flange plate and the maximum stress is less than the allowable stress 235 MPa of the material, which is in the reliable range.

分析结果表明，最大的应力变化出现在法兰盖板中心的热影响区，对盖板表面裂纹有主要的影响，最大应力小于材料的许用应力235 MPa。

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％。