预应力钢筋混凝土

The relationship between stress and strain of concrete in prestressed concrete bridge s is written as algebraic form within load duration and the equilibrium equations of internal force and compatibility conditions are introduced.

首先将预应力混凝土桥梁中考虑收缩、徐变影响的任意时刻混凝土应力、应变关系在持荷时段内写成代数形式，引入内力平衡方程及变形协调条件后，提出了计入截面上钢筋位置、配筋率、预应力钢筋松弛、混凝土弹性模量随时间变化等影响的徐变效应分析的全量形式自动递进法，并建立了计算式，适用于任何形式的收缩、徐变特性表达式；基于建立的全量形式公式，可方便地求解任意时刻混凝土、钢筋的应力与应变和梁体竖向变形。

At present, China's traditional concrete products, such as concrete and reinforced concrete pipes, self-stress pipes, prestressed pipe, reinforced concrete pole, and prestressed concrete poles, prestressed concrete sleeper, asbestos cement, and in the small Bova Bova, asbestos cement tubes, etc., these products production capacity and actual production, most of them can meet the needs of the market, there are many species more than the actual market requirements.

目前，我国传统的水泥制品，如混凝土和钢筋混凝土排水管、自应力管、预应力管、钢筋混凝土电杆和预应力混凝土电杆、预应力混凝土轨枕、石棉水泥小波瓦和中波瓦、石棉水泥管等，这些产品的生产能力和实际产量，大都能满足市场需要，有许多品种已超过市场的实际需要量。

Pre-stressed composite space truss is one of the new kind of space structure systems developed on the basis of prestress and space truss, which consists of steel and reinforced concrete. At present the study in this field is just being begun in our country. Therefore, in this paper static and dynamic performances of pre-stressed composite space truss associated with a practical engineering are studied, in addition, dynamic test on construction site and model experiment are done. Finally, we conclude this structure is well in stress and stiffness and dynamic characteristics.

预应力组合网架是一种基于网架和预应力技术发展起来的由钢和钢筋混凝土组合而成的新型预应力空间结构体系，目前国内在此领域的研究和应用都较少，为此，本文结合实际工程对预应力组合网架进行了静力和动力的分析研究，并作了施工现场的动力测试及模型试验，总结出预应力组合网架受力比较合理，刚度、动力特性好，是值得推广的一种空间结构形式。

The prestressed concrete simple beam compares reinforced concrete beam to compare, the merit includes: Uses the high marking concrete, section minification, the dead weight reduces, may increase the spanning ability; Uses the high strength steel bar, may save the steel products; But raises the sorghum body large scale the crack resistance, increases beam's durability, the concrete total cross-section bearing, has fully displayed the concrete resistant to compression performance superiority, also enhanced Liang's rigidity.

预应力混凝土简支梁较钢筋混凝土梁相比，优点有：采用高标号混凝土，截面尺寸减小，梁体自重减轻，可以增大跨越能力；采用高强度的钢筋，可节约钢材；可大幅度提高梁体的抗裂性，增加梁的耐久性，混凝土全截面受压，充分发挥了混凝土抗压性能的优势，也提高了梁的刚度。

The parameters included drag-span ratio of cable,the value of prestressing force,the thickness of reinforced concrete floor,the cross area of tightwire and the number of prestressed tig.

利用ANSYS有限元分析软件建立了钢筋混凝土楼板模型和预应力空间组合结构模型，对楼板模型和预应力空间组合结构模型分别进行了模态分析，同时分析了垂跨比、预应力度、拉索截面面积、纵向连接索数和楼板厚度对预应力空间组合结构自振特性的影响

The flexural capacity, deformation and failure modes of beams with different parameters can be analyzed using the program, such as types of plan and prestressed tendons(extrenal prestessed tendons, internal unbonded prestressed tendons, internal bonded prestressed tendons), jacking and effective stress in external prestressed tendons, configuration of the deviators, properties of tendon, ratio of span to effective depth of the beam and load pattern, initial loading state at tendon jacking, etc.(3) Nonlinear behaviors of the concrete beam prestressed with external or internal unbonded tendons were studied by the program developed.

本程序可以对任意截面型式的预应力(体外预应力筋、体内无粘结预应力筋、体内有粘结预应力筋)混凝土梁和普通钢筋混凝土梁进行非线性全过程数值分析计算，程序可以就转向块的布置方式、体外预应力筋纵断面形状、体外筋有效预应力的大小及材性、张拉预应力筋时梁的持荷状态等因素对体外预应力混凝土梁在外荷载作用下的强度、变形特征、破坏模式等的影响进行分析研究。

In the static test on Yi'an Bridge in Chongyi,we take a detailed examination and analysis about the flexivity、reinforcement stress、concete stress、steel wires stress of the steel-reinforced concrete、the low prestressing concrete and the full prestressing concrete on the twenty-meter long beam.

在崇义义安桥的静载试验中，对20 米标准跨径的普通钢筋混凝土、低预应力混凝土、全预应力混凝土空心板梁在均布荷载作用下的控制截面的挠度，钢筋、混凝土、钢绞线的应力作了较详细的试验、分析。

Taking Xiaoxi Bridge as an example,the thesis brings forward the economical 、simple 、construct-convenient 、light-tonnage prestressing technique.According to Yi'an bridge in Chongyi,on the twenty-meter long beam,certain load, the low prestressing concrete takes a all-around contrast with the full prestressing concrete and steel-reinforced concrete.

本文以小溪桥为工程背景，提出了适合低预应力混凝土的经济实用、工艺简单、便于施工的小吨位预应力工艺技术；以崇义义安桥为工程实例，把低预应力混凝土与全预应力混凝土、钢筋混凝土在20m 跨径、一定荷载的作用下作了全方位的对比。

The main contents are as follows: the basic knowledge of reinforcement and concrete; the principle of ferroconcrete in structural design and computation; the computation of bearing capacity in the normal and oblique section of flexural member; the computation method of member in torsion, tension and compression; the computation of distortion and crack width in members of the ferroconcrete in the design principle, stress analysis and the computation of the bearing capacity in the pre-stressed concrete structure and give an outline of the tier building and multistoried building.

主要内容有：钢筋和混凝土材料的基本知识；钢筋混凝土机构设计计算原理、设计方法；受弯构件正截面、斜截面承载力计算；受弯受扭受拉构件的承载力计算方法；钢筋混凝土构件的变形和裂缝宽度计算；预应力混凝土结构设计原理、应力分析及承载力计算；并简要介绍多层及高层建筑物结构。

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。