查询词典 crack on

This paper mainly study on the algorithm of the evaluation and recognition of the highway asphaltum pavement crack, and mainly concentrate on the crack image processing and the recognition of the crack type.

本文主要是对公路路面裂缝的识别与检测算法进行原理性的研究，主要集中于裂缝图像的处理以及裂缝类型的识别两个方面。

Utilizing the tools of conformal mapping and Cauchy integral formula and so on, the SIFs at the crack tips are obtained, which can be reduced to the known results under the condition of limitation; For the third and the fourth section, the problems of arc crack and parabolic crack are researched in one dimensional hexagonal QCs.

第二节研究了一维六方准晶狭长体中双半无限共线裂纹问题，利用保角变换以及Cauchy积分公式等工具求得了裂尖处的应力强度因子，在极限的情况下可以还原为若干已有的结果。

Special solutions for the ring circular domain with crack surfaces acted on uniform compressive force, linear compressive force and linear shearing force are deduced in polar coordinate employed the eigenfunction expansion technique in the Hamiltonian system of elastic mechanics. Combined with the general solution for the above problems, the analytical solutions for crack tip fields with surfaces acted on the above three kinds of loads are obtained. These solutions offer theoretical basis to construct analytical elements for plastic analysis of crack.

从弹性力学哈密顿体系理论出发，利用平面弹性力学极坐标系下的本征向量展开求解，推导了环形圆形域裂纹边作用有均布压力、线性压力和均布剪切力情况下的特解，从而得到了裂纹表面作用有以上三种荷载情况下的裂纹尖端场的解析解，为进一步构造进行弹塑性裂纹分析的奇异解析元奠定了理论基础。

And the keytechniques are in the following:(1) The algorithm and program of intensified node arrangement near crack tip andalong crack line (2) The shape function calculation of point near crack based on visibility criteria (3) The contour integral method for calculation of stress intensify factor K_ⅠK_Ⅱ(4) The rock slope appraisal method using circular method, polygonal method orgraph theory method depending on the slope joints combination

程序实现的关键技术和算法如下：(1)沿裂隙结点布置及裂尖结点加密的算法及程序(2)采用可视准则的形函数算计算程序(3)围线积分计算复合型裂纹裂尖强度因子K_Ⅰ、K_Ⅱ的算法及程序(4)圆弧搜索法、折线搜索法和无网格—图论搜索法的算法及程序

Is the short crack structure may explain certain landform growth origin question in the short crack structure aspect's significance; The short crack structure causes the epeirogenesis causes the earth's crust material to be destructed this to contain the ore solution to provide the good migration channel and stores the place and so on five aspects.

在短裂构造方面的意义是短裂构造可以解释某些地貌发育的成因问题；短裂构造引起的地壳变形，使地壳物质遭到破坏，这就为含矿溶液提供了良好的迁移通道和贮存场所等五个方面。

In this paper, the 3-D finite element relocating mesh method is used to calculate the temperature field and the thermal creep stress field of spillway dam and mid level outlet dam in certain roller compacted concrete gravity dam, sensitivity analysis have been down with different parameters, such as placing temperature, the location of cooling pipe, cooling temperature, time for water supply, ascended-layer of concrete, intermissive time and different placing time, and the commendatory construction scheme have been put forward in such analysis; according by the test result on the two scheme of concrete aggregate combination (basalt as coarse aggregate and limestone as fine aggregate, basalt as coarse aggregate and basalt as fine aggregate), simulation analysis on temperature field and thermal creep stress field of the commendatory construction scheme have been down, and analysis have also been down on temperature field and thermal stress field of the two different aggregate combination, the result indicates that the spillway dam and mid level outlet dam which adopted these two aggregate combination can both satisfy the require of design crack resistance in concrete, furthermore limestone as fine is better than basalt as fine aggregate; the effect of summer water storage and winter water storage on the temperature field and thermal stress field have been analyzed, comparing with winter water storage, in summer water storage scheme the maximum tensile stress at abnormal concrete in upstream fill is decreased by 0.1～0.3MPa and there are no evidence change of the maximum tensile stress at other parts, which indicate that summer water storage is avail for the crack resistance of upstream fill; according to the simulation calculating result and comparing temperature simulation calculating results and temperature controlling measures of some similarity projects both completed and construction, synthesis appraise have been carried to the design temperature controlling measures of dam, and the temperature controlling measures of this project have been brought forward, all these have great reference value on the design of temperature controlling measures and the optimization of the construction scheme.

本文采用三维有限元浮动网格法仿真计算程序，对某碾压混凝土重力坝的溢流坝段和中孔坝段分别进行了三维有限元温度场和温度徐变应力仿真计算分析，对浇筑温度、冷却水管的布置方式、冷却水温、通水时间、浇筑升程和间歇时间、不同开始浇筑日期等参数进行了敏感性分析，在此基础上提出了推荐的施工方案；根据两种骨料方案(玄武岩粗骨料+灰岩细骨料方案；玄武岩粗骨料+玄武岩细骨料方案)的混凝土性能试验研究成果，对推荐的施工方案进行了温度场和温度徐变应力仿真计算，并对比分析了两种不同骨料情况下的温度场和温度应力，结果表明溢流坝段及中孔坝段采用上述两种骨料均能满足混凝土的抗裂设计要求，且灰岩细骨料优于玄武岩细骨料；计算分析了夏季蓄水和冬季蓄水对坝体温度场和温度应力的影响，夏季蓄水方案与冬季蓄水方案相比，坝体上游变态混凝土区域最大拉应力小0.1～0.3MPa，其他部位最大拉应力无明显变化，夏季蓄水对坝体上游面混凝土的抗裂有利；根据仿真计算成果并通过比较国内一些已建和在建的类似工程的温度仿真计算成果及采取的温控措施，对大坝的设计温控措施进行了综合评价，并提出了该工程的温控措施，对温控设计和优化施工方案具有重要参考价值。

The mechanical mechanism of crack formation and crack growth based on partial concentration of stress of the roadbed are discussed. Crack growth is controlled by tensile stress and crack growth angle which is controlled by shear stress.

就路堤应力集中现象来讨论裂纹的形成和扩展力学机理，即裂纹扩展主要受拉应力作用，而裂纹的扩展角受剪应力的控制。

Because manual seed points are not exactly located on the crack features, two methods are proposed to search the geometric crack features, such as crotches. Wavelet transformation, clumpping, thinning and crossing algorithm are processed sequentialy to reach the semi-automatic feature extraciton purpose. Depending on these seed points, crack tracks and edges are determined by the method in this paper. Local image registration is utilized to raise relative accuracy and acquire the expansion of concrete cracks.

由於人工种子点并非准确落在特徵点，因此在种子点座落区域取目标视窗，使用基底函数转换边界侦测、区域增长消除杂讯区块、裂缝区块骨骼细化，接著寻找裂缝交叉点及端点，准确寻找出种子点应座落的位置，以此位置匹配后时期裂缝影像种子点，续以侦测前后时期裂缝边界，利用局部套合求得高相对精度，求得裂缝成长的情况。

With analysing the the fatigue mechanism, the general mode of interply fatigue damage propagation is denoted by delamination length and crack density. Based on the power-law, the relationship between number of cycles and delamination length and crack density are established. The specimen is modeled as an equivalent six-ply material system. Starting with the analysis of interply stress, the interply shear stress under cyclic loading is calculated by using nonlinear three-demension FEA. According to the stage regularity of fatigue damage propagation, such models as average strain, effective modulus, ratio of delamination length and crack density, experimental relationship between crack density and effective modulus, are proposed by introducing subsection coefficient.

通过对疲劳机理的分析，确定了以脱层长度和裂纹密度表示的层间疲劳损伤演化的一般模式，利用指数法则建立了脱层长度和裂纹密度随疲劳循环周次变化的关系；从层间应力分析入手，以等效六层的材料模型对循环载荷下的层间剪切应力进行了三维非线性有限元分析；根据疲劳损伤扩展的阶段性，引入分段系数，分别建立了平均应变与载荷循环周次的分段线性模拟模型、有效刚度随载荷循环周次的变化关系模型、裂纹密度变化和脱层长度变化关系随载荷循环周次变化的分段线性模型以及疲劳裂纹密度和有效刚度关系的经验模型。

The experimental result shows that when the discharge time was more than 1.5μs, small crack emerged in the fuses due to mechanical force on the heated fuse, and the metallized layer would be evaporated as the crack became long enough to generate disruptive discharge. When the discharge time was less than 150ns, small crack emerged in the fuses due to the current heat, and the metallized layer would be evaporated as the crack became long enough to generate disruptive discharge.

实验结果表明：当熔丝的通流时间大于1.5 ms时，电流热效应产生的机械力使安全膜熔丝的金属层产生微小裂纹，当裂纹达到一定长度，两端发生击穿放电，金属层因蒸发而断开；当熔丝中通过较大的电流时，短时间内(50 ns)的电流热效应使熔丝金属层发生熔化产生裂纹，裂纹两端发生击穿放电，金属层因蒸发而断开。

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％。