钢筋混凝土

Longitudinal reinforcement has been modeled with discrete element and stirrup has been modeled with smeared element. Smeared element, stirrup has been modeled using membrane element in or on concrete isoperimetric element. The constitutive relationship and failure criterion for concrete is the inter-facial model.

在建立钢筋混凝土的有限元模型时，混凝土采用的单元为八节点六面体等参单元，钢筋单元分为两种情况，纵向钢筋采用分离式钢筋单元，箍筋采用埋藏式钢筋单元，即箍筋作为附着在混凝土等参数单元内或单元上的"膜单元"。

Base on the problem of large quantity fatigue loads on corroded R.C. structure and small quantity study of its mechanical property, bending resistance fatigue test of corroded R.C. beams is discussed in this paper. The influence of stress ratio and re-bar weight loss ratio on bending resistance fatigue performance of corroded R.C. beams are researched, and the relation between strains of corroded re-bars and fatigue life of beams are obtained. The main research contents and conclusions are as following: 1. Under the fatigue loads, the overstrain of concrete approximately coincidences three stages strain development and accumulation rule, and the mechanical property of concrete is deteriorated. The fatigue damage of concrete is accumulated. The overstrain of re-bars increases and the increase rate decreases.

鉴于实际工程中大量存在腐蚀钢筋混凝土结构承受反复荷载作用，但其力学性能研究不多的问题，本论文进行了锈蚀钢筋混凝土梁抗弯疲劳试验，研究了应力比和钢筋锈蚀率对锈蚀钢筋混凝土梁抗弯疲劳性能的影响，得出了锈蚀钢筋的应变与构件疲劳寿命之间的关系曲线，主要研究内容及结论如下：(1)在循环荷载下，混凝土残余变形基本符合三阶段变形规律，力学性能劣化，疲劳损伤积累。

Combining with the National Natural Science Foundation ofChina(No.50478032), following researches were done in this thesis: 1 The variation regularity of the ultimate anti-bending capacity of therectangular-sectioned beam with different corrosion has been obtained through thequalitative analysis of 48 beams (32 corroded beams and 12 comparing beams) withaccelerated corrosion; 2 The conclusion has been obtained that the strain of corroded steel bar andconcrete no longer fit in with the assumption of plane section through the analysis ofthe strain data, the strain relation of steel bar and concrete in the mid-span section ofvariously corroded beams at ultimate has been obtained. Through the building of newgeometric relation, the expression of the height of compressive area in the corrodedbeam with rectangular section has been deduced, and the formula with corrosion rateas the main variable for the anti-bending capacity of the corroded concrete beam hasbeen suggested and verified by experiment.; 3 The influence of steel bar corrosion and the concrete regression to the flexureductility coefficient of the corroded structure component has been analyzed. Based onthe relation of steel bar and concrete at yield and ultimate, the expression for theflexure at yield and ultimate of corroded reinforced concrete beam, and the model forthe calculation of the flexure ductility has been built.

本文结合国家自然科学基金项目(50478032)"既有钢筋混凝土桥梁时变可靠度研究"，主要进行了以下研究工作： 1通过对48根快速锈蚀钢筋混凝土矩形截面梁(32根锈蚀梁和12根对比试验梁)数据的定性分析，得到了不同锈蚀率下，锈蚀钢筋混凝土矩形截面梁极限抗弯承载力的变化规律； 2通过对应变数据的分析，论证了锈蚀构件钢筋和混凝土的应变不再符合平截面假定的结论，并通过回归分析得出了不同锈蚀率的螺纹钢筋梁和光圆钢筋梁在极限弯矩作用下，跨中截面处钢筋应变和钢筋处混凝土应变的关系，通过构造新的几何关系，得出了锈蚀钢筋混凝土矩形截面梁计算受压区高度的表达式，既而得出了以锈蚀率为主要变量的锈蚀钢筋混凝土矩形截面梁的正截面抗弯计算建议公式，并通过试验数据加以验证； 3分析了钢筋锈蚀和混凝土劣化对锈蚀构件曲率延性系数的影响，结合钢筋屈服和极限弯矩两种状态下钢筋和混凝土的应变关系，分别得到了锈蚀钢筋混凝土矩形截面梁屈服曲率和极限曲率的计算表达式；既而推导出曲率延性系数的计算模型。

Existing literature on the inquiry,collation and analysis,this article had the following major tasks:1st,finite element simulation of the current analytical methods are summarized,and system introduction finite element software ADINA and ANSYS applied in the reinforced concrete built-up section.2nd,system introduction reinforced concrete component material performance as well as reinforced concrete nonlinear analysis main mathematical model. 3rd,the use of ANSYS and ADINA software simply supported beam simulation were compared.4th,uses the ANSYS analysis software,conducted 7 radical center bearing reinforcing steel-side steel pipe concrete short stump simulation test research,the research had indicated the reinforcing steel the existence strengthened the pillar ductility greatly.5th,based on ANSYS,has conducted 2 radical center bearing reinforcing steel-side steel pipe concrete member in bending simulation test research.

通过对现有文献的查询、整理及分析，本文进行了以下主要工作：1、对目前有限元模拟分析方法进行了总结，并系统的介绍了有限元软件ADINA和ANSYS在钢筋混凝土组合结构中应用。2、系统的介绍了钢筋混凝土构件的材料性能以及钢筋混凝土非线性分析的主要数学模型。3、利用ANSYS和ADINA软件对简支梁进行了对比模拟分析。4、利用ANSYS分析软件，进行了7根轴心受压钢骨-方钢管混凝土短柱的模拟试验研究，研究表明钢骨的存在大大加强了柱子的延性。5、利用ANSYS分析软件，进行了2根轴心受压钢骨-方钢管混凝土受弯构件的模拟试验研究。

The paper also indicates that influence of vertical crack on reinforcement rustiness is smaller than lengthwise crack, concrete basicity, concrete carbonate and so on.

钢筋锈蚀是导致钢筋混凝土结构耐久性等级下降的主要原因之一，本文根据工程调查，分析了混凝土状况对钢筋锈蚀程度的影响，认为垂直裂缝对钢筋锈蚀的影响程度远小于纵向裂缝、混凝土碱度、碳化等其它因素。

Its amount has relation with acting load. The influence on sectional curvature of bending components is the greatest one, the ultimate curvature of corroding section decrease obviously, and the sectional curvature increases rather sharply with the increase of rust rate during the process of corrosion. The anti-cracking capacity of prestressed bending R. C. components may be damage. For the convenience of engineering usage and damage evaluation of structure, this paper presents a concept of sectional damage coefficient on the foundation of experimental and treatment study.

试验与理论研究均表明，受压区钢筋锈蚀后对普通钢筋混凝土和预应力钢筋混凝土受弯构件的承载力影响均不大，但对构件的正常使用性能有较显著的影响，受压区钢筋锈蚀过程中，截面刚度有较显著的下降，挠度及受压区混凝土压应变随锈蚀量增加而增加，增加值与使用荷载大小有关；受弯构件的截面曲率所受影响最大，锈蚀后截面的极限曲率有明显的下降，在使用荷载作用下，截面曲率则随钢筋锈蚀量的增加而有较显著的增加；而预应力混凝土受弯构件的抗裂度会下降。

Decades, the system does not always produce pipes, tiles, cement products and other traditional rod, but the development should be high (high-strength, high pressure) and large, new (new building materials and products) as a key to develop new products In detail: to develop high-strength prestressed concrete pile; apply to set up more than 110 kilovolt high voltage transmission lines and electrified railway lines, etc. Catenary large t m poles; application of new high-speed heavy rail with pre-stressed concrete sleeper; high-pressure , large-diameter prestressed concrete cylinder pipe; steel concrete and prestressed steel-concrete composite pipe; new type of reinforced concrete pipes, such as the mouth and socket bearing steel reinforced concrete pipes, square pipes, short-shaped pipes, common drains ; reinforced concrete inspection and; urban and rural construction using a variety of hollow interior wall panels and composite wall panels, concrete hollow block.

不能几十年一贯制生产管、瓦、杆等传统水泥制品，更应把发展高、大、新作为重点开发新产品，具体讲：大力发展预应力高强混凝土桩；适用于架设110 千伏以上高压输电线路和电气化铁路接触网线路等的大吨米电杆；适用高速重载铁路用的新型预应力混凝土轨枕；高压、大口径预应力钢筒混凝土管；钢板混凝土和预应力钢板混凝土复合管件；新型钢筋混凝土排水管，如钢承口和承插式钢筋混凝土排水管、方型渠、短形渠、共同渠；钢筋混凝土检查并；城乡建设用的各种空心内墙板和复合外墙板、混凝土空心砌块。

The durability of concrete structure in general air environment, including concrete carbonization mechanism and influencing factors, steel corrosion mechanism and influences to the structural mechanical performance, cracks of concrete caused by the expansion of corrosion and the relation between width of crack and amount of corrosion, and the life estimation of reinforced concrete structure. At the same time, the paper introduced durability paint for concrete of xichang Cable-stayed bridge.

一般大气环境下普通钢筋混凝土结构的耐久性，包括混凝土碳化机理及影响因素、钢筋锈蚀机理及对结构力学性能影响、混凝土锈胀开裂及裂缝宽度与锈蚀量之间的关系以及钢筋混凝土结构寿命评价等，并利用以上理论对西昌斜拉桥钢筋混凝土塔柱进行了预测分析。

In this paper,one contrast reinforced concrete short column and three reinforced concrete short columns strengthened with concrete and exterior steel plate were tested to investigate their shear behaviors,based on experiment results,it is revealed that complex strengthening with concrete and exterior steel plate can impactful improving shear bearing capacity of reinforced concrete short column.

进行了1根对比钢筋混凝土短柱和3根用混凝土和外包钢板复合加固钢筋混凝土短柱的受剪试验研究，试验结果表明，用混凝土和外包钢板复合加固可有效提高钢筋混凝土短柱的斜截面抗剪承载力。

In a market economy, enterprises must attach great importance to technological progress, and to take practical actions to achieve universal adoption of concrete admixtures; scored with ribbed steel bars of variable cross-section to replace the glossy steel as the production of prestressed Concrete products and reinforced concrete products, reinforced; concrete mixing system to the early realization of microcomputer control; by roll welding machine to replace the hand-made steel skeleton of banding; centrifugal molding, product testing, as well as a phase of water pressure of the pressurized pipe to achieve the conservation process of automatic control ; vigorously promote energy conservation, etc.

在市场经济条件下，企业必须高度重视技术进步，并采取可行的措施，尽快实现普遍采用混凝土外加剂；用带肋刻痕的变截面钢筋取代光面钢筋作为生产预应力混凝土制品和钢筋混凝土制品的配筋；混凝土搅拌系统要尽早实现微机控制；用滚焊机取代手工绑扎制作钢筋骨架；离心成型、产品水压检验以及一阶段制管的加压养护过程实现自动控制；大力推广节能养护窑等等。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。