查询词典 crack on

To give the definition of the mass concrete and to concrete\'s cracks together with practical meanings of control ,and give a brief review on the research in the field at home and abroad, at last, methods to control temperature crack of the mass concrete from several aspects such as design measures,concrets material, construction schedules.etc are summed up; To explain the physical mechanics of the concrete and computing methods-Difference Method and Finite Element Method, and illustrate the application of their specific methods repectively;Several temperature factors that can influence the temperature stress of mass concrete baseplate are analyzed. The influence degree of temperature factor can be got through the ANSYS simulation computation the control of temperature can control the temperature stress, consequently control the temperature crack of mass concert baseplate; through the influence of the crack resistance ability of mass concrete baseplate which takes the reinforcement as a part is analyzed. By ANSYS simulation, the best suited volume ratio of reinforcement is found out, at same time the layout of reinforcement with the same volume ratio can also affect the resistance ability of mass concrete baseplate. Sum up of above analysis, anti-crack function of steel bar in early mass concrete baseplate is obvious, so it\'s necessary to consider beneficial effect of construction steel bar in research of temperature control on mass concrete baseplate.

本文先容了大体积混凝土及混凝土裂缝的基本概念，对国内外在这个领域里的研究现状作了扼要叙述，并从结构设计、混凝土材质、施工措施等方面总结了大体积混凝土温度裂缝控制的方法及防止措施；阐述了混凝土的基本物理力学性能，总结了大体积混凝土温度计算的方法——差分法和有限元法，并分别举例说明其具体应用的方法；分析了影响大体积混凝土底板温度应力的几种温度因素，利用ANSYS模拟计算，得出了每种因素的影响程度，通过分析提出了在这几种温度影响因素下如何通过控制温度以达到控制温度应力从而来控制裂缝的具体建议；针对大体积混凝土基础底板中配筋的不同对混凝土底板抗裂能力的影响不同，利用ANSYS进行模拟分析，得出底板中最合适的体积配筋率，同时分析了在相同体积配筋率下钢筋的具体布置对大体积混凝土基础底板抗裂能力的影响，分析表明，配置钢筋对混凝土结构的开裂阻止作用明显，在研究大体积混凝土温度裂缝题目时，要考虑钢筋在其中的有利作用。

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。

Based on fuzzy feature that the concrete crack width affects concrete structure durability, the membership function that the crack width belongs to the durability failure is established, the calculation method of fuzzy probability about structure durability failure is submitted, and classifing standard of the sturucture durability state is proposed, In accordance with the stochastic nature that cracks on concrete bridges occur and grow, and by assuming that crack occurrence obeys nonstable Poission process, predicting and evaluating methods about future crack condition and durability state of concrete bridge structures are suggested.

依混凝土裂缝宽度对混凝土结构耐久性影响的模糊特性，建立了裂缝宽度隶属耐久性失效的隶属函数，提出了结构耐久性失效的模糊概率计算方法，并建议了结构耐久性状态的划分标准；针对混凝土桥梁裂缝发生、发展的随机性，以裂缝的发生服从非稳态的泊松过程的假设为前提，提出了混凝土桥梁结构裂缝未来状况及耐久性未来状态的预测评估方法。

Sepal 5, fu covers with tiles shape is arranged, chang Sucun, corollaceous bell form, funnel form, tall foot butterfly form or earthen jar form, brim ministry is shallow 5 crack or deep 5 crack, rotate when bud or tweezers closes account; Staminal 5, on canister of move unripe Yu Guan, hide inside or appear, pollen bead does not have thorn or aculeate, on ovary, often be a cup of shape or surround for flower disc place of dissension, 1-4 room, every room contains 1-2 bead ovule, style 1-2, post is not cracked or 2 crack, rare 3 crack, or 2-4 is cracked.

萼片5片，覆瓦状排列，常宿存，花冠钟形。漏斗形。高脚蝶形或瓮形，檐部浅5裂或深5裂，芽时旋转或镊合状；雄蕊5枚，着生于冠筒上，内藏或外露，花粉粒无刺或有刺，子房上位，常为杯状或为分裂的花盘所包围，1-4室，每室含1-2粒胚珠，花柱1-2个，柱头不裂或2裂，稀3裂，或2-4裂。

Secondly, the paper carries on the destruction processes and the stress distribution situation numerical simulation of the concrete three point bending specimen with bias crack under static load function,, and analyze specimen crack expansion and the destruction mechanism, obtain the reason that the crack expanding flectional way is because the material nonuniformity, in the same time, from the specimen destruction process chart we can see that the crack bias degree has some influence on the crack expansion way.

其次论文对含偏置裂纹的混凝土三点弯曲试件在静态载荷作用下的破坏过程和应力分布情况进行了数值模拟，并对试件的裂纹扩展和破坏机理进行了分析，得出裂纹扩展的曲折性是由于材料不均匀性所引起的，同时从试件的破坏过程图中可以看出，裂纹的偏置程度对裂纹的扩展路径有一定的影响。

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。

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。。。

Wu Sun-fu stopped abruptly, bringing his forefinger down with a crack on the table to emphasize his point, his face beaming self-righteously

划然停止了，吴荪甫&义形于色&地举起左手的食指在桌子边上猛击一下。

This paper analyses the reasons of crack on the cold saw blade from Laigang Heavy H-Beam production line.

介绍了莱钢大型H型钢生产线冷锯锯片产生裂纹原因的研究与分析。

The results of conversion show that the serious disc must be rejected because its reliable L-HCCF life is greatly less than an overhaul period. Finally, the load distribution of centrifugal and vibration force on labe is derived. Using two method, load on the crack labe gradually reducing and keeping constant with the crack propagation, a crack propagation analysis of fir-tree slot is carried out, and the calculating L-HCCF crack propagation life of slot on the unload method, which is nearly 3 times longer than that on constant method, is 20 times shorter than the pure low cycle life, and agree well with the experimental's.

最后，分析了离心力载荷和振动载荷在榫齿上的分布，进行了榫槽榫齿的有限元计算；提出了枞树型榫槽的卸载概念，并按带裂纹榫齿上的承载随裂纹增长而逐步减少和始终保持不变两种处理方法，进行了复合疲劳裂纹扩展及其寿命计算，由计算得出卸载下复合疲劳裂纹扩展寿命较单纯低周疲劳寿命下降二十多倍；按卸载处理的疲劳裂纹扩展寿命是按恒载处理的三倍多，前者与试验吻合，而后者则偏差较大。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。