无应力的

Based on the ICMmethod,the discrete topological optimization problem about spot-weld's existence or not is transformed into the continuous optimization problem on[0,1].The optimization model is founded with maximizing the structural stiffness as objective and structural strength as constraints.The problem of multi-objectives and multi-constraints is transformed into the problem of single-objective and single-constraint with the K-S function.The displacement and stress are transformed into the explicit function of design variables with the Response Surface Methodology.The optimization model is solved with Sequential Quadratic Program.

基于ICM（Independent Continuous Mapping，即独立、连续、映射）方法，将焊点有无的离散拓扑优化问题转化为[0，1]区间上的连续优化问题；建立了以结构刚度最大为目标、结构强度为约束的连续拓扑优化模型；采用K-S函数将多目标和多约束问题转化为单目标和单约束问题；运用响应面方法将位移和应力转化为设计变量的显式函数，采用序列二次规划方法求解优化模型。

The selection of fracture splitting forceparameter mainly depends on experience and no theory can abide by.In this paper aim at the technique of fracture splitting of engine connectingrod, the materials fitting to fracture splitting have been analysed, according tosome influence factors that the former has researched. The influence that thechemistry compositions to the mechanics function and the physical function insteel have been analyzed. The theory of quasistatic fracture splitting of suitableconnecting rod for engine EA827 has been studied. Aimed at the new materialC70S6, the quasistatic procedure has been numerical simulation analyzed bySPH non-mesh method. The solved stress intensity factor module andparameterize model building module have been developed based ANSYS byAPDL.

本论文主要研究发动机连杆裂解工艺，根据已知的一些连杆裂解影响因素，对适合裂解的连杆材料进行了综合分析，分析了钢中各组成化学成分对力学性能和物理性能的影响，针对新型裂解连杆材料C70S6钢，对捷达EA827发动机配套连杆进行了准静态裂解理论分析，并且利用SPH无网格方法对此进行了数值模拟分析，利用APDL开发了基于ANSYS的求解连杆裂解应力强度因子模块和参数化建模模块。

Hypoplastic constitutive theory, which was originated from the middle and late stage of the 20th century, is a new type of soil constitutive theory based on rational mechanics. Hypoplastic theory can reflect inelasticity, nonlinearity, dilatancy and other main mechanical properties of granular material.

亚塑性本构理论是20世纪中晚期发展起来的一类基于有理力学的新型的连续介质本构建模理论，主要用于刻画无黏性散粒型上体的非弹性、非线性及剪胀性等主要应力应变特性。

Based on the analysis of the results of these two cases, the rule of element's σ, at different position is presented, and it shows that the steel panel can effectively reduce the maximal σ, of the element adjacent to the steel panel, and can postpone the arriving time within the simulation time. At the same time, the simulation reveals that the boundary effects don't affect the spalling in the similar structure presented in this paper.

通过对两种情况下的结果分析，揭示了混凝土不同位置处单元σ值的时程规律，得到了在计算时间内钢板的存在能够有效地减小相邻混凝土单元的最大拉应力，并延长其出现时间；同时得到了在类似研究的工程结构中，边界效应对混凝土层裂现象无影响。

In this case ,experimental analysis is needed in order to extend the new type.

在无成熟设计理论的情况下，要推广这一新型节点，除了进行详细的有限元分析以外，还需要借助于试验的手段，对节点的破坏形态、应力分布等情况进行深入研究，同时，检验有限元计算模型的可靠性。

In this paper,about the body of a special ultra-heavy semitrailer without beam,its model is built in ProE sofeware and its static analysis and modal analysis,which is in static state ,constant speed traction state and braking state, are performed in Ansys software.Displacement distribution,stress distrbution,the first five inherence frequencies and vibration modals are educed.

本文针对超重型特种无梁半挂罐车的罐体，用ProE软件建立起模型，用Ansys软件进行罐体在静载工况，匀速牵引工况及制动工况时的静态分析和模态分析，得出罐体在各种工况下的位移分布，应力分布及前五阶自振频率和振型，以验证该罐体设计的合理性。

Use the finite element software ANSYS to make model for consecutive strands and unbonded prepressed concrete lining. Build the reciprocity relation of the cells in consecutive strands and cells in RC, analyse the stress and transmogrification of consecutive strands and RC to make sure the design parameter can meet the need of specification.

2采用有限元分析软件ANSYS，分别对无粘结预应力衬砌方案的预应力钢绞线和钢筋混凝土衬砌单独建模，预应力钢绞线的单元节点与钢筋混凝土单元间通过约束方程法建立起相互作用的关系，分析钢绞线和钢筋混凝土衬砌的应力和变形，计算结果表明确认采用的设计参数能够满足规范要求。

The stess yielding mechanism of aged atactic polystyrene was studied by use of mechanical tension, differential scanning calorimetry and solvent-swelling.

利用机械拉伸、示差扫描量热以及溶剂溶胀等方法研究了物理老化后的无规聚苯乙烯的应力屈服行为，并从凝聚缠结的观点对实验结果进行了解释。

According to former reports, with the high stress from lateral pressure obstruction, the gutta pertscha become the primary cause of tooth root diastema of pulpless teeth.

据以往的文献报道，由于侧方加压充填时产生的高应力，侧方加压充填牙胶尖是造成无髓牙牙根纵裂的最主要原因。

And through the double-loaded fatigue experiments, the results fit well with the model.

含孔复合材料层合板的疲劳行为试验研究结果表明，该复合材料含孔层合板具有优越的拉-拉疲劳性能，在高应力水平以下能够经历106以上的载荷循环，且无明显目测损伤。

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％。