回弹

In this investigation, the compression behavior of COx argillite with two different grain size distributions, which were obtained by two different crush procedures, was studied by running 1D compression tests with several loading-unloading cycles.

通过开展一维压缩试验，研究2种不同粉碎工艺下获得的粗／细COx土样的压缩特性，结果表明：压缩曲线受粒度成分的影响非常明显，为获得同等压实度，细粒土所需的压实功能较粗粒土高，除此之外，细粒土的压缩指数也高于粗粒土，表现出较强的压缩性；随着土样压实密度的增加，粗／细土样的压缩曲线逐渐靠拢，粒度成分对压实功能影响逐渐减弱；土样卸荷时回弹指数随干密度的增加而增加，受粒度成分的影响不明显；高压实ρ(下标 d=2.0g/立方公分粗粒土样在7 MPa的轴向应力下饱和时，体积发生明显的塌陷现象，饱和后土样的压缩指数小于饱和前，而回弹指数则较饱和前高。

By analyzing the process of bending cross beam , this article elaborates different factors that affect the resilience under different conditions, from which we find out solution for resilience.

通过弯曲横梁的工艺分析，在不同的条件下，影响回弹的因素也不同，从中找出解决回弹的方法，用一套补偿回弹量的弯曲模来完成该件的制做。

The method of springback finite-element for large deflection of plate shaping is established on springback potential energy principle that is already concluded.

通过引入有限变形回弹反耦联系统和反耦联方程的概念，由回弹势能原理建立了板成形的大挠度回弹有限元法。

Therefore it is necessary to research the mechanism of greensand used for high compacted molding methods thoroughly.This subject is one section of the National Natural Science Foundation subject ""Ivestigation on Predicting Method and Mechanism of Springback for High Compacted Sand Molds"", followed of the other completed one named ""Research on Microdeformation of Molding Sand"". A serious of experiments has been done on the reequipped three axial machine under certain technological conditions, and the mechanics, material science, rheologic science. It is systematically studied that the influences on the springback of sand mold were caused by the main influence factors: pressure, compacted rate and the content of soil. Through the analyzed experiments' data, the experienced stress-strain relationship concerning the main influence factors were obtained;under different technical parameter, the springback and spingback's potential energy are compared, the differences and indifferences between them are found out, and the springback's mechanism is discussed;according to the tests' data of YangGuoping coming from Tinghua University, experienced formula of molding sand's springback displacement is induced, the displacement and springback are compared, the margin of error's reasons are analyzed, and they are tested and verified mutually.

本课题为国家自然科学基金项目"高紧实度砂型预测方法及回弹机理的探讨"的一部分，是已结题的国家自然科学基金项目"铸造型砂微变形的研究"的后继，运用力学、材料学及流变学理论，利用改装的三轴仪，在一定的工艺条件下，作了大量系列实验，系统的研究了压实比压、紧实率和膨润土含量对砂型回弹的影响；对实验数据进行了分析和处理，得出了型砂关于压实比压、紧实率和膨润土含量的本构关系的经验公式；把各工艺参数下的型砂产生的回弹量与回弹势能进行比较，找出两者存在的异同点，并对回弹机理进行了探讨；通过清华大学杨国平的实验数据，推导出型砂回弹位移场的经验公式，并与实验测出的回弹量进行比较，分析误差造成的原因，并互相进行了验证。

By deep analyzing the tested value of the concrete strength with the rebound method and combining with the inverse regression theory,a rebound strength curve of three-parameter inverse regression is put forward.

基于对回弹法检测混凝土强度被检测量，结合逆回归理论提出了一种逆回归三参数回弹法测强曲线模型，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。

Present the rebounding ratio, and analyse the relationship of degree of slope,rebounding value and stability, point out that rebounding ratio is a important factor of effecting the stability of slope, and discuss the relationship of lumpiness ,rebounding value ,rebounding ratio, JRC ,height of slope and the degree of slope, confirm the influencing degree of all kinds of factors to the degree of slope, and the order is lumpiness,rebounding value,rebounding ratio,JRC and the degree of slope.

提出了回弹比，分析其与坡度、稳定性间的相关关系，指出回弹比是对边坡稳定性影响的一个重要因素。确定了各因素对坡度的影响的重要性依次是块度、回弹值、回弹比、JRC和坡高。

The research results show as follows. As plastic deformation increases, the Young's modulus of material continuously changes. This variation law is able to be described using a piecewise linear function .Hardening model and whether the variation is considered or not make great effet on springback prediction. It is proved that the springback prediction result which adopts the elastic-plastic constitutive model based on INLK hardening model and the variation of Young's modulus is considered, is more close to experimental result. After the sheet metal undergoes multiple bending, the corner radius and bending height also affect springback greatly.But the effect trend is different. At the same time, the reliability of springback research using numerical simulation is proved.

研究结果表明：材料弹性模量随塑性变形的变化是不断变化的，该变化规律可用分段线性函数进行描述；强化模型及考虑弹性模量变化与否对回弹预测有很大的影响，基于INLK强化模型和考虑弹性模量变化的弹塑性本构模型对回弹的预测结果与试验最接近；多次弯曲中圆角半径与弯曲高度对板料变形后的回弹有较大影响，但影响趋势不同；证明了数值模拟方法对回弹研究的可靠性。

Three types of subgrade filling material are selected to analyze the change rule of subgrade resilience modulus under different compaction. Meanwhile PFWD（portable falling wei-ght deflectometer） is combined to integrate this parameter with compaction of construction control index,which brings about the conversion relation between three subgrade filling material and compaction. It can provide reference for pavement design and construction.

选定三种不同类型的路基填料，分析在不同压实度条件下路基回弹模量的变化规律，并结合PFWD检测方法，将设计参数回弹模量与施工控制指标压实度联系起来，得出三种路基填料的回弹模量与压实度的转换关系，可为路面设计与施工提供合理的依据。

The spring back in the distortion process was predicted by finite element method, and the predicted results were analyzed to find out the reason lead to spring back, and so as to precompensate the spring back.

利用有限元仿真对其变形过程中的回弹进行预测，并对预测结果进行研究，找出回弹根源，从而对其回弹进行预先补偿。

The study shows that the effect of Young's modulus is largest, then hardening coefficient, initial yielding stress, hardening exponent and anisotropy r0 . While the effects of anisotropies r4 5 and r9 0 variation can be ignored.

研究结果表明，杨氏模量的波动对板料回弹量的影响最大，其次分别为硬化系数、初始屈服应力、硬化指数及各向异性系数r0的波动，而各向异性系数r4 5及r9 0的波动对板料回弹量的影响可忽略，且数值模拟分析材料参数对板料回弹量的影响趋势与理论分析一致。

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