查询词典 rod crack

The main research tasks and results are as follows:(1) Through comparing the stress intensity factor of compact tension specimen calculated by finite element software with the theoretical value, the feasibility of calculating fracture parameters of crack tip in ABAQUS software was verified.(2) The relationship between the elastic modulus of the material and research scale was studied based on deriving the cohesive stress theory and other relevant theories. And the elastic modulus of the material on meso-scale was determined.(3) Global model and sub-model of the finite element were built in th...e macro-scale, and stress-strain field nearby the crack tip was analyzed, and the results show that the detailed stress-strain in the crack tip could be obtained by using the sub-model technique.(4) In meso-scale, the crack growth model was also established by assuming the crack propagating along the grain boundary, and the detailed stress-strain field in the crack tip was obtained.(5) The effect of crack length on Von Mises stress, and maximum principal stress and strain was analyzed in meso-scale when equivalent KI equals 30MPa.m1/2. And the results show that except for crack tip area, the stress-strain distribution in whole specimen is not affected.

主要完成研究内容和取得成果如下：(1)利用有限元软件计算出紧凑拉伸试样的裂纹尖端应力强度因子KI值，其结果与理论值一致，从而验证了利用ABAQUS计算裂纹尖端相关断裂参量的可行性；(2)在研究内聚应力等相关理论的基础上，推导出了研究尺度与材料弹性模量的近似关系，并确定了介观尺度上的弹性模量；(3)在宏观尺度上建立了全局有限元计算模型和子模型，得到了裂纹尖端应力应变场分布，结果表明利用子模型技术获得比较准确的裂纹尖端应力应变场分布是可行的；(4)在介观尺度上利用平均晶粒尺度的方式建立了裂纹沿晶扩展模型，得到了裂纹尖端断裂过程区的微观应力应变场；(5)当应力强度因子为30MPa.m1/2时，分析了介观尺度上在裂纹沿晶扩展过程中裂纹长度对Mises应力、最大主应力和应变的影响，结果表明，裂纹扩展长度对试样整体应力应变分布影响不大，而对裂纹尖端区域有较大影响；(6)介。。。

Crack propagation problems under the influence of the edges of the crack subjected to homogenous loads, the origin of the coordinates subjected to concentrated increasing loads, the central zone of the edges of the crack subjected to homogenous loads, the certain point of the edges of the crack subjected to moving unit step loads, the origin of the coordinates subjected to moving increasing loads Px m, the edges of the crack subjected to instantaneous impulse loads, the edges of the crack subjected to moving concentrated variable loads, the origin of the coordinates subjected to point loads, the edges of the crack subjected to a constant moving concentrated loads and the origin of the coordinates subjected to instantaneously moving impulse loads are studied respectively, and the analytical solutions of dislocation distribution function have been obtained.

同时对裂纹面受均布载荷、坐标原点受集中增加载荷、裂纹面中心区受均布载荷、裂纹面上某点受运动阶跃载荷、坐标原点受运动增加载荷Px m、坐标原点受瞬时冲击载荷、裂纹面受运动集中变载荷、坐标原点受集中载荷、裂纹面受常数运动集中载荷、坐标原点受瞬时运动冲击载荷作用下的裂纹扩展问题分别进行了研究，获得了位错分布函数的解析解。

The crack that see much of most in several residence is that a layer maneuver a wall to hand over to connect place to have the stairs form the crack creation;Hand over to connect place or beam bottom and wall body to have the level crack the creation in the house noodles and the wall body;There is Shu under the first floor window sill toward the crack creation, the window sill of each floor two wall window way outside the layer four Cape existence inclined crack;Small scaled and hollow carve in the reinforced concrete pillar and the Mao a piece of fill a wall of mutually knot existence the Shu is to the crack;It is carve a piece periphery a creation crack.

随着国家保护耕地措施的实施，粘土砖的使用逐步得到控制，砼小型空心砌块在住宅工程中开始得到越来越多的应用期刊文章分类查询，尽在期刊图书馆在多层住宅中最常看到的裂缝是顶层纵横墙交接处有阶梯形裂缝产生；在屋面与墙体交接处或梁底与墙体间有水平裂缝产生；在底层窗台下有竖向裂缝产生，各个楼层的窗台两角和顶层外墙窗口四角处有斜裂缝存在；在钢筋混凝土柱和砼小型空心砌块填充墙的相结处有竖向裂缝存在；在砌块周边产生裂缝。

The crack that see much of most in several residence is that a layer maneuver a wall to hand over to connect place to have the stairs form the crack creation;Hand over to connect place or beam bottom and wall body to have the level crack the creation in the house noodles and the wall body;There is Shu under the first floor window sill toward the crack creation, the window sill of each floor two wall window way outside the layer four Cape existence inclined crack;Small scaled and hollow carve in the reinforced concrete pillar and the Mao a piece of fill a wall of mutually knot existence the Shu is to the crack;It is carve a piece periphery a creation crack.

随着国家保护耕地措施的实施，粘土砖的使用逐步得到控制，砼小型空心砌块在住宅工程中开始得到越来越多的应用在多层住宅中最常看到的裂缝是顶层纵横墙交接处有阶梯形裂缝产生；在屋面与墙体交接处或梁底与墙体间有水平裂缝产生；在底层窗台下有竖向裂缝产生，各个楼层的窗台两角和顶层外墙窗口四角处有斜裂缝存在；在钢筋混凝土柱和砼小型空心砌块填充墙的相结处有竖向裂缝存在；在砌块周边产生裂缝。

It is clarified for the first time that the thermal fatigue failure of solder joint is actually a creep strain low cycle fatigue failure, and a physical model for creep fatigue crack propagation has been proposed. It was pointed out that creep strain increases in the high stress area ahead of the tip of thermal fatigue crack, results on one hand that the slide of crack tip increase, inactivation more serious and crack close length increases, the other hand, that intergranular crack exists, whose direction will affect the fatigue crack propagating.

本文首次阐明了焊点的热循环失效本质上是以焊点内循环蠕变为主要应变的低周疲劳失效，并在此基础上提出了蠕变疲劳裂纹扩展的物理模型，指出热循环裂纹前端的高应力区内，蠕变加剧，使裂纹前端滑移增加，裂纹钝化加剧，导致随后的裂纹闭合扩展长度增加；同时蠕变也使裂纹前端的高应力区出现晶间裂纹，蠕变沿晶裂纹对主裂纹扩展的影响取决于沿晶裂纹的连接方向。

According to the plane cross section assumption, configuration of a rod is expressed as a history of the cross section with arc coordinate. A special solution which stands for equilibrium in straight line state is obtained from differential equilibrium equation. Linear perturbation equation is derived and its general solution is obtained in which the integral constants are determined by constrained conditions at two ends of the rod. The condition of existence of non zero solution of the integral constants gives to the Greenhill formula of exact elastic rod model, which shows that the boundary of stable area is a closed curve and of symmetry, and inference of shearable and extensible to stability of the rod is depend on three factors: difference between flexibility of shear and extension of a section of the rod, bending stiffness and the length of the rod.

基于平面截面假定，弹性杆的位形表达为截面的弧坐标历程，根据平衡微分方程得到了两端受力螺旋作用时的直线平衡特解，导出了线性化扰动方程及其通解，积分常数根据两端铰支时的边界条件确定，并根据其存在非零解的条件得到弹性直杆精确模型的Greenhill公式，表明稳定域为一对称的封闭区域，拉/压和剪切对稳定性的影响取决于：拉/压柔度与剪切柔度之差，抗弯刚度和杆长这三个因素

Adopt at present most advanced large-scale SUPER SAP finite element structure analyse procedure to go on numerical value calculation for model of drilling rod, drilling rod whole stress simulation of state that receive show and reflect drilling rod various kinds of stresses under different working states distribute the characteristic clearly, make stress state of drilling rod reach visual, make people able to understand informations of drilling rod of stress status in depth too at the same time, so that the design of the improvement drilling rod constantly is in order to meet the demands of actual project.

采用当前最先进的大型SUPER SAP有限元结构分析程序对钻杆的模型进行了数值计算，得到的钻杆整体应力状态的模拟显示清楚地反映了钻杆在不同工作状态下的各种应力分布特征，同时也使钻杆的应力状态达到了可视化，使人们可以深入了解钻杆应力状态信息，以便不断的改进钻杆的设计以满足实际工程的需要。

At the same time, sales of wear resistant welding rod, cast iron welding rod, stainless steel welding rod, casting tungsten carbide welding rod, low carbon steel welding rod, factory products:úspecial wear-resistant electrode, Sham Tseng bit special wear-resistant electrode, with wear-resistant welding rod mill, cement brick special wear-resistant electrode, pears seeder cultivator blades and other special wear-resistant electrode, the above Domestic Product of several ministerial-level enterprise year-round use.

同时销售耐磨焊条、铸铁焊条、不锈钢焊条、铸造碳化钨焊条、低碳钢焊条，本厂拳头产品：木炭机专用耐磨焊条、深井钻头专用耐磨焊条、粉碎机用耐磨焊条、砖瓦厂水泥厂专用耐磨焊条、播种机旋耕梨刀片专用耐磨焊条等，以上产品数家国内厅部级企业常年使用。

In this paper, the factors that may cause crack breaking of concrete pavement of several built highways were analyzed systematically and thoroughly. From analysis to site experiments and calculation, it is believed that crack breaking is mainly caused by factors as follows: 1 、 Unqualified sedimentation and losing stabilization of the roadbedinduced crack in the early; 2、 Construction technology、 materials and incorrect treatment methodswere adopted;3 、 Crack breaking induced by thermal stress; 4、 Water cant circulate makes crack cause;With regard to the afore-mentioned problems, corresponding preventive measures, qualified control indices and site control approach are presented based on analysis theory and site experiments.

本文在全面系统地分析已建成的高速公路水泥混凝土路面产生的原因的基础上，通过现场试验及计算分析，确定了高速公路水泥混凝土路面裂缝的主要影响因素有以下几个方面： 1、路基的不均匀沉降、失稳是早期裂缝产生的主要因素； 2、施工工艺、材料问题及养护方法不当； 3、温度应力产生的裂缝； 4、排水不畅影响裂缝产生；针对上述问题，通过理论分析及现场数据提出相应的质量控制目标、现场控制方法。

The application of reflected optical difference system in surface crack of aluminum detection is also discussed. By analyzing the experimental data, we found that the reflected pulsed wave techniques could be used to measure the position of crack precisely and depth imprecisely. Transmitted wave contain much size information of the crack, despite without position information. The spectrum of transmitted is sensitive to the depth of crack. The deeper the crack is, the narrower the spectrum bandwidth is.

使用自建的光偏转差分检测系统，对铝样品中多种表面缺陷进行了检测，对表面波直达波，反射波，透射波波形及频谱进行了分析，讨论超声表面波与各种缺陷相互作用后的变化，通过对实验结果的分析，发现缺陷脉冲发射法可以精确测定缺陷位置，粗略估计缺陷深度；而透射法测的波形无法定出缺陷位置，但包含了缺陷大小信息，透射波频谱对缺陷深度非常敏感，随缺陷深度的加深，频谱不断的左移。

He's a pretty westernised kind of guy.

他是一个非常西化的人。

National spirit is the moral kingpin for a nation to realize common ideal and goal.

一、中华民族精神的基本内涵党的十六大报告指出：在五千多年的发展中，中华民族形成了以爱国主义为核心的团结统一、爱好和平、勤劳勇敢、自强不息的伟大民族精神。