回弹

A method is proposed which modified the forming surface of element group in the Multi-point forming by iterative ways according to the numerical simulation results.

基于数值模拟的结果，提出了修正基本体群成形面补偿回弹，获得精确形状零件的方法，并描述了该方法的主要步骤。

Asphalt mixture; compression module; lvdt; extensimeter; temperature

沥青混合料；回弹模量；顶面法；侧面法；温度

In the experiment, we mainly analysis the module, frost heaving, thaw settlement in freezes under the condition to the subgrade soil, the soakage change rule have carried on the actual, and have carried on fast and slow experiment contrast analysis in several primary factors that affected the roadbed to freeze the characteristic: The initial moisture content, the freeze speed, the load and so on.

试验中，重点对路基土在冰冻条件下，回弹模量、冻胀、融沉、吸水量的变化规律进行了实测分析，并对影响路基冰冻特性的几个主要因素：初始压实度、冻结速度、荷载等进行了快速、慢速试验的对比分析。

Good agreement is found between the theoretical predictions and the experimental results in the springback of hemispherical parts.

利用该算法对半球形零件的拉深回弹进行了预测，所得结果与实验结果吻合较好。

To attain the same strength grade, the content of cement in cement fly-ash stabilized hoggin has reduced by 0.5~1% comparing with cement stabilized hoggin. This material has a capability of adapting with different aggregate's gradation and the 4.75mm passing rate can reduce to 30%. Through the studying about the mechanical property of cement fly-ash stabilized hoggin, this manuscript discover that the material has good strength growing performance that its 90d strength growing rate is 385% and its splitting strength that the 7d splitting strength is 0.347MPa and the 90d splitting strength is 0.700MPa accord with requirement in the norm.

粉煤灰处于最佳掺量时，通过粉煤灰的填充、活性等作用，使材料在达到相同强度等级，水泥剂量降低0.5～1%；并且对集料级配具有更好的适应性能且能使集料4.75mm以下通过率降低至30%左右；而且能有效提高材料的强度增长率，90d强度增长率高达385%左右；同时，降低回弹模量16%左右，对材料的抗裂性能有显著的改善作用。

The main theorem of this paper is to, firstly, on the grounds of experience preliminarily estimate the parameter of the pavement nonlinear model, simulate the process with computer procedure, and check the result with the data collected in sit, then set the aim function and the superiority back-calculation method, if the function is not satisfied, it is to the method adjust the parameter and make the model impend the actuality, If the function is satisfied, it is to end the process, and record the stress, deformation, displacement and the parameter as the actual condition.

本文分析的主要原理：首先根据经验，初估路面结构层应力应变非线性参数，利用计算机程序模拟承载板试验测回弹弯沉的过程，通过现场实测的弯沉数据来检核该模拟过程的真实性，设定目标函数，选定适当的优化反算方法，当目标函数不满足时，即利用该优化反算方法调整本构模型参数，使得模型能够逐步向真实解逼近，当目标函数得到满足时，则认为此时反算得到的路面结构层的应力、应变、位移场为真实的应力、应变、位移场，所推算得到的非线性应力应变模型为真实的路面结构层应力应变模型。

Influence of simulation parameters on simulation precision of the springback, such as elements type, material types, constitutive equations, integral point selections, contact conditions, friction rules, and like that, has been analyzed.

分析总结了数值模拟中模拟参数（有限无算法、单元类型、材料模型、本构方程、积分点选取、接触和摩擦法则等）对回弹模拟精度的影响。

To use isostasy theory, this paper analyzes the causes of the great earthquakes. The loading amount of the Tibetan Plateau is reduced by glacial ablation, the springback of the top of the upper crust is caused. The isostasy is broken and the great earthquake is induced.

运用地壳均衡理论，分析了近年来青藏高原周缘地区特大地震的成因，即随着全球气候的变暖，青藏高原大陆冰川迅速消融，冰川的消融使青藏高原的荷载量突然减轻，触发了下地壳顶面的回弹，进而产生了向上的垂向力，打破了地壳的均衡和青藏高原地壳表层的负载平衡，诱发了青藏高原周缘地区频频发生特大地震。

Four-node degenerated shell element and rigid shell element are used in our FEM model.Updated Lagrange formulation and rate form constitutive equation are adopted to solve the problem of large strain and large rotation in sheet forming process.Sheet metal material property is described by plastic anisotropy yielding model and isotropic hardening model.Master surface-slave surface contact model is used to define the contact between tools and blank.Contact constraints are enforced with a kinematic algorithm and friction stress is computed by Coulomb friction law.Dynamic relaxation method is used to treat springback after forming stroke.

四结点蜕化壳单元和刚体壳单元分别用来建立板和模具的有限元模型；更新Lagrange法和速率型本构关系被用来处理板料变形中的大应变和大转动；材料模型采用塑性各向异性屈服与等向强化模型；通过主从面模型定义板料和模具的接触，接触算法采用运动约束法，摩擦力用库仓定律计算；并利用动力松弛法对回弹过程进行了计算。

In the curve, the concrete rebound value with wide randomness is a dependent variable, while the compressive strength value with narrow randomness is an independent variable, and a location parameter is added, so it is more suitable for engineering practice.

将随机性较大的混凝土回弹值作为因变量，随机性较小的抗压强度值作为自变量，并且增加了一个位置参数，更加符合工程的实际情况。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了