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By applying contour integral method and high-order displacement functionsof MM,we obtain the accurate stress intensity factors of mixed-mode crack.Then,the open crack propagation of the mixed mode I and II is simulated by means oftheories of linear elastic fracture mechanics.This provides a simple and effectivenumerical way for crack evolvement studying.

接着，文中采用围线积分法和流形方法的高阶位移函数来计算得到比较准确的混合型裂纹尖端的应力强度因子，然后基于线弹性断裂力学的裂纹扩展准则，用流形方法实现了平面I-II混合型张裂纹扩展的数值模拟，为数值方法研究裂纹的演化行为提供了一条简单而有效的途径。

Crack growth direction of V-notch column sample under tensile-pressural loading was found by means of simulating the crack growth path side by side analyzing the distribution of Von Minses equivalent stress of the V-notch sample, the result shows crack growth direction of the sample under tensile-pressural loading is diametral direction of circle where the V-notch lies.

通过边分析试样的Von Minses等效应力分布，边模拟裂纹扩展方向的方法对拉压载荷下V型切口试样的裂纹扩展方向进行了模拟，结果显示V型切口试样在拉压状态下的裂纹扩展方向为棒料V型切口处圆周的直径方向。

In this paper, a method is proposed to estimate the plastic zone size, by extending the Dugdale model to three dimensional (3D) crack problems and the crack opening displacement at the tip of a sptatial penny shaped crack by combining the Barenblatt Dugdale model with the principle of 3D J integral, then the relationship between J integral and COD is obtained.

将Dugdale模型推广到三维裂纹问题计算了圆盘状裂纹前缘塑性区尺寸，并结合断裂力学中的Barenblat－Dugdale裂纹模型和三维J－积分原理计算了圆盘状裂纹前缘张开位移，得到了J－积分与裂纹张开位移的关系。

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。

Indicated according to the near two year gauge block anti-curved experiment, when the design intensity takes 435 N/mm2, under the normal running condition the reinforcement stress probably is 343 N/mm2, the corresponding average crack opening approximately in the 0.14~0.15mm scope, if takes 1.66 to multiply the big coefficient, the short-term maximum crack opening reaches 0.24mm, considered the long-term function rides 1.5 to multiply the big coefficient again, final crack opening approximately in 0.36mm.

根据近两年对板的抗弯试验表明，当设计强度取 435 N / mm2，正常使用状态下钢筋应力大约为 343 N / mm2，对应的平均裂缝宽度大约在0.14～0.15mm 范围，如取1.66倍增大系数，短期最大裂缝宽度达 0.24mm ，考虑长期作用再乘1.5倍增大系数，最终裂缝宽度大约在0.36mm 。

In the same way failure area is not single andis more complex with decrease of scale of specimens. And failure shape ismore close to quasi-brittle failure. It varies with homogeneousness that thescale of specimens at which failure shape changes.(3) The failure shape of homogeneous specimens with crack is controlledby crack. But that of heterogeneous specimens with crack is controlled bycrack and heterogeneousness.(4) Acoustic emission doesnt appear until homogeneous specimens fail.

但对于不同均质度，试件破坏形态发生变化的尺度也不同；(3)对于均质度较高的含裂纹试件，试件的破坏形态主要受裂纹控制，而对于均质度较差的含裂纹试件，试件的破坏形态由试件材料的非均匀性和裂纹共同控制；(4)均质度较高的试件，破坏前，试件内不出现声发射，破坏瞬间，声发射在某些部位同时出现，且随尺度增大，试件声发射能量增大，声发射区趋于集中。

Theobserved strain is 10~2 times as local point strain at the same observed stress.This indicates that macroscopical symmetrical rock is quasi-brittle materialwith microcosmic heterogeneousness and its macroscopical mechanicalbehavior is the results of reciprocity and magnification between microcosmiccharacteristic, not simple sum.(4) The degree of irregularity of strain increases with the number of cycle.But degree of irregularity of transverse strain fluctuates larger at the samecycle. Moreover degree of irregularity of transverse strain is larger than that ofaxial strain. This shows that deformation and failure of rock is process ofevolvement of small crack. Small crack evolves from even and out-of-orderstatus to heterogeneous and ordinal status.(5) Ultrasonic speed decreases with the number of cycle. The decreasecourse is such: Firstly, ultrasonic speed fluctuates in a steady scope in somecycles; And then ultrasonic speed quickly decreases to a certain more smallvalue; Afterwards in succedent cycles, ultrasonic speed fluctuates about thevalue. That is to say, ultrasonic speed fluctuates and decreases at intervals ofcycles. In deformation process of rock, quantitative change and qualitativechange of its small crack evolvement carry through crosswise.(6) Strength and modulus of rock decrease with exponential function asscale of specimens increases.

同一表观应力下，局部点应变与表观应变相差可达2个数量级，表明宏观上均匀的岩石是具有细观特征的准脆性材料，其宏观力学行为是细观特征相互作用、放大的综合结果，而不是简单的叠加；(4)岩样轴向应变不均匀程度和横向应变不均匀程度随循环次数的增加渐进增大，但是在同一个循环内，横向应变离散系数随应力的变化波动较大，且同一循环级别下，横向应变不均匀程度大于轴向应变不均匀程度，表明岩石内部微裂纹的演化是岩石变形破坏的本质特征，这一演化表现为微裂纹从均匀无序分布逐渐向非均匀有序发展；(5)随循环次数的增加，所有岩样内部超声波速会出现衰减，衰减过程表现为在某几次循环内超声波速在某一相对范围内波动，然后急剧减小到某一较小值，在随后的循环内，超声波速又会保持在这一较小值附近波动，即超声波速表现为波动和急剧减小间隔形式衰减，表明从宏观看来平稳的岩石变形过程，内部结构演化过程(微裂纹发展及其相互作用)却表现为均匀量变和突发质变不断交叉进行的现象；(6)岩石强度和弹性模量随尺度增大呈指数函数规律减小。

Plane strain, mode I quasi-static steady state crack growth is investigated utilizing the finite element method. It is once again established that TNT plasticity can significantly increase the stress level near the crack tip. The crack tip stress singularity is higher than or equal to the square-root singularity of elastic K field and is also independent of the plastic hardening exponent.

采用有限元方法研究了平面应变Ⅰ型准静态的稳态裂纹扩展，再次证实TNT非局部理论能够显著提高裂纹尖端附近的应力水平；裂尖应力场的奇异性超过或等于弹性K场平方根奇异性，而且与塑性硬化指数无关。

On the research of the propagation of the fatigue crack in the past 10 years, Paris and Zheng-hart have developed good formulas of the propagation of the fatigue crack of metal , but of which only describe the process of the propagation of the fatigue crack.

在近几十年对疲劳裂纹的扩展的研究中，Paris和Zheng-hirt对金属材料疲劳裂纹扩展的研究给出了很好的扩展表达式，但都是对疲劳裂纹扩展部分过程的描述。

Based on the fundamental principles of the improved method mentioned above, multi-functional computation software package, which can be used to analyze effectively the interference effects of random flaws in plane problem, boundary problem and space problem, is compiled and a number of problems involved in the interference effects of different kinds of flaws such as random equal length through-cracks, random branched throughcracks, random unequal length through-cracks, random holes to through-cracks, unequal length edge cracks, equal length and distance multiple edge cracks, random notches with different aspect ratio, random notch to edge crack, non-coplanar surface cracks with different aspect ratio, staggered surface cracks, surface crack to embedded crack and embedded cracks near free boundary are analyzed and computed by the package.

依据上述改进法的基本原理，本文编制了能有效地分析平面问题，边界问题及空间问题的任意缺陷群相互干涉效应的多功能计算软件包。据此，本文分析计算了各类缺陷群。诸如，任意等长裂纹群。任意折裂纹群；任意不等长裂纹群，任意孔与裂纹群，不等长边裂纹群。等长等间距多裂纹群，任意形状比缺口群，任意缺口与边裂纹，非共面不同形状比表面裂纹群，交错型表面裂纹群，表面裂纹与埋藏裂纹群及自由边界附近埋藏裂纹群等的相互干涉效应问题。

"Bird Man's Diary, Butting on the Love Island", Changsha, China

2008年"鸟人日记，顶在爱情岛"，中国长沙

As long as they were in the service of a family of wizards, their magic would remain dormant.

只要他们一天为家庭服务，他们的法力就潜藏不动。