【作者】 周莉娜；

【导师】 何雄君；

【作者基本信息】 武汉理工大学 ， 结构工程， 2003， 硕士

【摘要】 随着我国高速公路建设的蓬勃发展，桥梁建设进入了前所未有的高潮时期。在各种桥型中，大跨预应力混凝土梁桥以其独特的优势被广泛应用，近年来得到了较快的发展。 从设计的角度而言，它具有如下的特点：一是设计与施工方法密切相关，尤其是其合理预应力体系的获得，是一个极其烦琐的过程。设计者需根据所确定的施工方案和工序及设计内力包络图，配置预应力束筋，满足各工序的预应力要求。对其中任一工序，尤其是超静定结构，其所配预应力束筋又导致内力重分配，因而需要反复调整，直到满足要求；二是在施工图的绘制方面。预应力钢束因其线形变化多，大都又呈曲线状，而对于大型复杂的预应力结构，如连续梁桥，往往有几百根钢束，几十种形状，所以钢束图的绘制任务繁重。此外，由于工作量大，数据繁多、计算和绘图中很容易发生差错，导致设计、计算和图纸数据的不一致。而人工绘图不仅劳动强度大，效率低、质量也无法得到保证。因此，迫切需要CAD技术辅助设计这类桥梁。这对于提高桥梁设计效率，增强企业竞争力具有十分重要的意义。 本文针对现有的桥梁CAD系统的不足，从工程实际应用的角度出发，初步构想了预应力混凝土梁桥CAD系统的框架，并主要在其自动配束以及预应力钢束布置图的自动绘制方面作了一定的分析与研究：在配束方面，根据其设计的特点及存在预应力束调配过程烦琐的现象，引入数学方法，基于模糊集合和预应力度的概念，初步探讨了连续梁桥预应力钢束自动配置的机理；在钢束图的绘制上，根据对钢束特点的分析，提出了“钢束模型”的概念，对预应力束进行描述，并给出了控制“钢束模型”以及钢束布置的参数，据此，作者采用FORTRAN语言编写了钢束布置图的绘制程序，实现了钢束布置图的自动绘制。本文采用DXF这种文件格式对图形进行存储，使系统不仅能与AutoCAD进行图形数据交换，还能与其它应用程序进行交换，从而扩大了系统的适用范围。对于编制出的程序，作者通过其在工程实例——襄樊四桥纵向预应力布置图绘制中的应用，证明了它的实用性。同时根据它在实际应用中的不足，为今后更进一步的工作指明了方向。更多还原

【Abstract】 With the rapid development of highways in our country, bridge construction has come in the upsurge period which is unknown before. And among the various bridge types, the long span prestressed concrete beam bridge is widely used for its advantages, and then has being developed rapidly.The long span prestressed concrete bridge has typical characteristics in its design: one is that its design is closely related to construction method, and because of the system transferring during its construction it is difficult to obtain its rational prestressing system. It is affected by many factors, such as construction method, creep secondary internal forces, secondary internal forces caused by exerted indeterminate structure and so on; the other is in the working drawing of the prestressing cables. Normally there are hundreds of cables in a continuous beam bridge, especially in an indeterminate structure. And the shape of the prestressing cable is complicated, so it has great difficulties in its drawing. So it is urgent to develop the CAD system of such a kind of bridge.Based on such characteristics and the researches of the country and outside, this paper mainly studies at the automatic distribution of prestressing cables of prestressed concrete beam bridge and the automatic working drawing of the steel bundles.In this paper, based on the study of the group of the project, it sets up a fuzzy optimum math-model of the prestressed degree for prestressing cables disposition of prestressed concrete continuous beam bridges. And in the drawing of the steel bundles, the set up of the "prestressing cable model" makes its courseconvenient. And it used such a file type-DXF, to save the drawing. Thus itmake it freely to exchange date with AutoCAD and other applications.Then it gives an example of the engineering application-Xiangfan SiQiao. And at last, several valuable conclusions are summarized, some shortages and the future research orientation are also put forward at the same time.更多还原