大跨预应力混凝土连续梁桥施工控制研究及温度效应分析

【作者】 汪剑；

【导师】 方志； 梁建国；

【作者基本信息】 湖南大学 ， 桥梁与隧道工程， 2003， 硕士

【摘要】 连续梁桥由于其变形小、结构刚度好、养护简易等优点，使其在现代大跨度桥梁结构中处于有利的竞争地位，因此有必要对连续梁桥的施工技术作更进一步的研究。由于灰色预测控制具有适时性好、较强的鲁棒性以及控制简便等特点，并且能够基于连续梁桥施工的未来态势作超前一步预测，做到防患于未然。因此本文结合衡阳东阳渡湘江大桥的修建，运用灰色预测控制系统，对大桥上部结构施工过程中的内力和线形状态进行预测控制。大桥施工完毕后，各控制结果均满足预期要求，分析表明，灰色预测控制适用于大跨预应力混凝土连续梁桥的施工控制，并可将其推广到其它桥型的施工控制中。由于在连续梁桥的施工过程中，日照温差是影响连续梁桥施工正常进行的一个重要问题，而解决此类问题的先决条件是箱梁内温度场的确定，因此本文对施工中的以及成桥后的连续梁桥进行了24小时的连续观测，基于此实测数据，进行了详细的分析，其结果表明温度效应分析的正确与否主要取决于温度模式的选取，并且得出了采用指数分布的温度模式较符合实际的结论，另外还提出了在不影响施工进度的前提下，对主梁立模标高进行主动修正来考虑日照温差影响的方法。更多还原

【Abstract】 With its good mechanical behavior and easily maintenance,continuous beam bridge occupies the competitive position in morden long-span bridges. And it is necessary to do more research on the construction technology for the bridges. On the basis of the constructing of Dongyangdu Bridge across the XiangJiang river in Hengyang,Hunan,using the method based upon the grey predictive control system to forecast pre-camber of bridge segment, a more advanced control system-grey predictive control system for the construction of long-span PC continuous beam bridge has been developed. After the construction is accomplished, the results indicate that the grey predictive control system is adapted to the construction control for the long-span PC Continuous Beam Bridge. During the constructing of the bridge, the stresses caused by sunshine are important factors affecting its normal construct schedule. To solve the problem,the precondition is to make the temperature gradients and temperature variation of box grider clear. Therefore, this paper makes a thorough analysis of the effect of temperature difference and draws some reasonable conclusions after the tests of the temperature gradients, internal force and the deformation of continuous bridge for 24 hours a day. And a method is developed in this paper to make an active revise to the elevation of the main girder form on the premise of no influence to the bridge construct schedule.更多还原