有限元法

The presterssed anchor cable frame combined with backwall, drainage is necessary due to longtime sability and permanent utilization.Firstly,according the study of engineering of geology situation of the high slope, the mechanism of deformation failure and the major hazard of the high slope of PanMei is analysed comprehensively.And the whole slope is divided into two different geology enginnering areas:Western slope(1160 section plane -1240 section plane)and Eastern slope(1240 section plane -1320 section plane). The result of 3D numerical simulation is the same as geology judgement. Later,slope cut (1:0.75) is implemented based on the engineering comparison and criterion.Meanwhile, Limit equilibrium method , Monte Carlo Probabilistic slope stability the stability , Sensitivity analysis and Finent element method of for assessing the cutted slope stability is carried out. The result indicates that Western slope is instable, Eastern slope is relatively stable.So much attention should be paid to Western slope.Different reinforcement measures in different areas are given according to its stability and meet economical request. Gravity wall is introduced in accordance with landform in order to prevent small falling at the foot of the high slope ,which will be a threat to the high slope stability. Handling measure is also applied to Eastern slope. At last,FLAC3D numerical analysis shows the feasibility and reasonableness of the handling measure of the high slope.

论文首先研究了边坡的工程地质条件，全面分析边坡的变形破坏机制和边坡的主要地质灾害，将边坡分为西段不稳定边坡区(1160剖面～1240剖面)和东段相对稳定边坡区(1240剖面～1320剖面)，通过三维数值模拟再现了边坡在自重作用下的破坏机制和过程；在此基础上通过工程类比和规范要求，确定按照1：0.75进行放坡处理，并分析了放坡后边坡的稳定性状况，分别通过极限平衡法、蒙特卡洛法概率分析、参数敏感性分析和有限元稳定性计算等多种方法对边坡在各种工况下的进行稳定性研究，计算结果表明，西段边坡较之东段边坡稳定情况差，是边坡支护的关键之处，而东段边坡相对是稳定的；边坡的综合治理措施选用的是框架锚索并结合挡土墙和排水工程，治理设计根据不同区段的稳定性情况采用不同的支护结构，做到了经济合理的要求；在边坡的坡脚设置重力式挡土墙，防治边坡小规模的崩塌，会对上部的锚索支护护造成不利影响，进而影响边坡的稳定；东段边坡的填方区也给出了治理对策；最后通过三维显示拉各朗日有限差分程序(FLAC3D)模拟了高边坡放坡和支护效果，论证了治理措施的有效性和合理性。

In this paper, the stress and strain distribution, tube wall thinning and the cross section ovalization in Aluminum alloy thin-walled tube NC bending with small bending radius have been investigated through experimental method combined with finite element method and theoretical analysis.

本文采用实验法，并结合有限元模拟和理论解析法，研究了与铝合金薄壁管小弯曲半径数控弯曲成形质量密切相关的应力应变分布、壁厚变化和截面畸变等关键问题。

In the present study, through using non-linear three dimensional finite element analysis, considering the contact in flange to nut and flange to gasket, we accurately computed the stress distribution in the flange joint in the normal work condition.

采用ANSYB软件，应用三维有限元技术，考虑了垫片的非线性和法兰和螺母、垫片的接触问题，并且采用了螺栓预紧单元，准确计算出法兰连接在承受内压、轴向力和弯矩外荷载时的应力分布。

It offers analysis of electric field intensity distribution of connecting junctures and high voltage oil cable terminal boxes.

基于有限元方法，用最小能量法和电荷守恒法计算含有悬浮导体的电场强度分布，分析了高压充油电缆终端盒以及电缆连接接头的电场强度分布。

Energy method was used to yield a formula to compute critical load of plates with stiffeners. Finite element method was followed to test it and give some advice to engineering design of stiffeners.

文中给出了从能量法推出的设加劲肋的板的临界应力系数的计算公式，并与有限元数值法分析的结果进行比较，得出的结论可用于指导工程设计。

Then by using FEM to calculate the direct and quadrature axis magnetic fields, the steady-state reactances x〓 and x〓 are determined with definition method and vector potential method when μ〓 equals ∞ and voltage equals 0.1U〓 and U〓 respectively.

接下来，以有限元为工具，在直轴和交轴磁场下，用定义法和矢量位法，分别确定μ〓=∞、0.1U〓和U〓状态下的稳态电抗x〓和x〓以及在额定负载下确定x〓和x〓的饱和值，并研究了直、交轴间的耦合电抗以及用路的方法确定稳态电抗。

The primary work and remarks of the paper are as follows:(1) Stress intensity factors of gun barrel under inner pressure are obtained by finite element method. The accuracy of displacement method and stress method are compared. Some patterns of dynamic stress intensity factor are studied.

论文所做的主要工作和研究成果如下：(1)通过有限元方法计算了身管在内压作用下的应力强度因子，比较了位移法和应力法的精度，并且研究了动态应力强度因子的规律性。

There are two methods to evaluate the safety of arch dam, such as overload method and synthetic method.

采用三维非线性有限元，以累积自重和设计水压为基本荷载，利用超载法和部分的超载、强度降低的综合法分析了某高拱坝的失稳破坏过程，得到其整体安全系数和破坏特征。

In the process of building and using the mass concrete structures, because of the effect of out-side condition and themselves, some faults will form in the structure, these faults will effect the bearing capability and endurance Using nondestructive testing method to test the concrete"s quality and diagnose its healthy, which has the significant sense in assessing the safety stability and research of the administering diseasesThis dissertation mostly researched the testing methods in the mass concrete structure, discussed the principles, methods, features, sphere of application of the ultrasonic testing in the mass concrete structure with faults, used dynamic FEM to simulate the testing process, discussed when the concrete structure with cracks is under the effect of the pulse, how the elastic waves propagate and what are their changing feature, Researched the principles of the first-arriving waves" phase when the cracks" depths are not same, obtained the relation between the inversion point and the cracks" depth, which has the direction sense in the application of projects,The second part of this dissertation is CT , which used the ultrasonic wave running through the tested-substance to get arriving-time of the ultrasonic wave, then inverse the image This dissertation drawed one CT program which can well present the different little cells ultrasonic wave velocity profiles of the substance, thereby to diagnose the quality of the part of the tested-substance, CT has the better using foreground..

在混凝土结构的施工及使用过程中，由于受其自身及外界各种因素的影响，常常会产生一些缺陷，对结构物的承载能力和耐久性造成严重影响，采用无损检测技术进行质量检测和健康诊断，这对混凝土结构开展安全、稳定性评估以及病害隐患治理研究具有重要意义。本论文主要针对大体积混凝土结构缺陷的检测方法展开研究工作，重点讨论了超声波法检测混凝土结构裂缝的基本原理和方法及其特点、适用范围，运用动力有限元数值模拟其检测过程，探讨了有裂缝缺陷的混凝土结构在脉冲荷载作用下弹性波的传播及其变化特征，研究了不同裂缝深度下首波相位变化规律，得出了反转临界点与裂缝深度之间的关系，这对实际工程应用具有指导意义。声波CT是一种新的无损检测技术，它是利用声波穿透被检测体获取声波接收时间，来进行计算机反演成像的技术。本文利用直射线法编制了层析成像程序，能较好地呈现被检测物体各微小单元的声波速度分布图像，从而对检测体的质量状况作出诊断评估，具有较好的应用发展前景。

In addition, the blank holding force that is required to avoid wrinkle and rupture during conical part deep drawing is researched. The necessity of reasonable blank holding force in pressing is expounded. From the view of mechanical analysis, the wrinkle critical condition of side-wall is derived for the first time by the stress state of side-wall, the main deformation region on blank. According to the critical condition of plastic instability for flange, side--wall, corner of punch on blank, The blank holding force in conical part deep drawing is divided into four different regions within its forming figure. The basic principle of reasonable blank holding force during stamping is summarized and provided. The mathematical model of reasonable blank holding force that avoids the wrinkle and rupture is established and verified by the finite element numerical simulation and the grid experiment method. The result shows that it is accurate and reliable.

此外，本文还研究了圆锥形件拉深成形过程中，随着拉深变形过程的进行，毛坯为避免产生起皱、破坏缺陷而对压边力的需求情况，阐明了圆锥形件拉深成形过程中压边力合理变化的必要性；由毛坯主要变形区悬空锥壁部分的受力变形情况，从力学分析的角度，首次推导得出了圆锥形零件悬空锥壁起皱失稳的临界条件；并根据主要变形区法兰、悬空锥壁及凸模圆角部分的塑性失稳临界条件，在其成形范围图中，将圆锥形件成形过程中的压边力划分为四个区域；总结并提出了圆锥形件成形过程中压边力合理变化的基本原则；建立了防止起皱、破坏缺陷产生的压边力合理变化的数学模式，并得到了有限元数值模拟及网格实验法的验证，证实了理论分析结果的正确性和可靠性。

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％。