既有无背索斜拉桥索力调整与内力分析

发布时间：2018-04-30 14:27

本文选题：无背索 + 斜拉桥　；参考：《东北林业大学》2014年硕士论文

【摘要】：无背索斜拉桥由于造型优美,经济适用等优点,建设日益增多,然而由于设计、施工和养护等原因,一些斜拉桥并没有处于一个合理的内力状态,存在一定的安全隐患。对既有无背索斜拉桥进行索力调整和内力分析在国内已修建的无背索斜拉桥中尚属首例,解决和研究这个问题十分必要。本文以大连市金州大桥主桥——主跨130m单塔单索面无背索斜拉桥为工程背景,对索力调整过程进行研究,本文主要研究内容和成果如下： 1、总结无背索斜拉桥的发展、特点,介绍既有斜拉桥索力调整的必要性及研究现状,阐述索力优化方法,根据结构最小余能原理建立目标优化函数,引入变形约束条件,确定索力调整目标值,介绍索力调整目标的实现过程。 2、分析金州大桥主桥当前实测线形和索力状态,并与规范、设计限值进行对比,索力最大偏差达到78.95%,主梁和主塔最大偏位值分别为-17cm和150cm,不满足限值要求。根据实测数据对有限元模型进行修改,分析结构当前所处的理论内力状态,应力不满足规范要求,进行索力变化灵敏度分析和恒载应力可行域分析,确定调索后结构合理的内力状态及对应的成桥索力。 3、提出两种不同的索力调整方案,以斜拉索索力、主梁应力和位移、主塔应力和偏位作为分析指标,比较各方案对其力学特性和线形特征的影响程度,采用均方差评价两种调索方案,发现从短索调至长索方案离散程度远大于从长索调至短索方案,选取后者作为实际调索方案,计算索力调整量及调索过程中各拉索的伸长量。 4、将确定的调索顺序应用到金州大桥主桥上,据该无背索斜拉桥的特点,确定施工工艺、原则及监控内容,并对金州大桥主桥进行施工监控,结果显示主梁位移误差不超过±0.3mm,最大偏差为7.4%,主塔纵向偏位误差在±2.5mm之内,结构应力实测值和计算值吻合程度很好,斜拉索误差在±3%以内,最大误差仅为1.58%,效果较好,成功完成了金州大桥主桥无背索斜拉桥调索工程。
[Abstract]:The construction of cable-stayed bridge without back cable is increasing due to its beautiful shape and economic applicability. However, due to design, construction and maintenance, some cable-stayed bridges are not in a reasonable state of internal force, and there are some hidden dangers of safety. The cable force adjustment and internal force analysis of the existing cable-stayed bridge without back cable is the first case of the existing cable-stayed bridge without back cable built in China. It is necessary to solve and study this problem. Based on the engineering background of the main bridge of Jinzhou Bridge in Dalian, the main span of 130m single tower and single cable plane cable-stayed bridge without back cable is studied in this paper. The main contents and results of this paper are as follows: 1. The development and characteristics of cable-stayed bridge without back cable are summarized, the necessity and research status of cable force adjustment of existing cable-stayed bridge are introduced, the optimization method of cable force is expounded, the objective optimization function is established according to the principle of minimum residual energy of structure, and the deformation constraint condition is introduced. The target value of cable force adjustment is determined, and the realization process of cable force adjustment goal is introduced. 2. The current measured line shape and cable force state of the main bridge of Jinzhou Bridge are analyzed. The maximum deviation of cable force is 78.95, the maximum deviation of main girder and main tower is -17cm and 150cm respectively, which does not meet the limit requirement. According to the measured data, the finite element model is modified to analyze the current theoretical internal force state of the structure, the stress does not meet the requirements of the code, the sensitivity analysis of cable force variation and the analysis of the feasible region of dead load stress are carried out. Determine the rational internal force state of the structure after cable adjustment and the corresponding bridge cable force. 3. Two kinds of cable force adjustment schemes are put forward, in which the cable force, the stress and displacement of the main beam, the stress and deflection of the main tower are taken as the analysis indexes, and the influence of each scheme on the mechanical and linear characteristics of the cable is compared. It is found that the dispersion from short cable to long cable is much larger than that from long to short cable. The latter is chosen as the actual cable adjustment scheme to calculate the cable force adjustment and the elongation of each cable in the process of cable adjustment. 4. The fixed cable adjustment sequence is applied to the main bridge of Jinzhou Bridge. According to the characteristics of the cable-stayed bridge without back cable, the construction technology, principle and monitoring contents are determined, and the construction monitoring of the main bridge of Jinzhou Bridge is carried out. The results show that the displacement error of the main beam is not more than 卤0.3 mm, the maximum deviation is 7.4mm, the longitudinal deviation error of the main tower is within 卤2.5mm, the measured value of the structural stress is in good agreement with the calculated value, the error of the stay cable is less than 卤3%, the maximum error is only 1.58 and the effect is good. Successfully completed the main bridge of Jinzhou Bridge no back cable cable-stayed bridge cable-adjusting project.
【学位授予单位】：东北林业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U448.27

【共引文献】