紫金大桥施工监控及关键技术研究

【作者】 王泽锋；

【导师】 乔建东； 吴察微；

【作者基本信息】 中南大学 ， 建筑与土木工程， 2009， 硕士

【摘要】 斜拉桥是高次超静定结构,它对成桥线形有较严格的要求,每个节点坐标的变化都会影响结构内力的分配。桥梁线形一旦偏离设计值,将导致内力偏离设计值。所以必须严格控制斜拉桥的施工过程,以保证合理的成桥线形及索力。本文以浙江丽水紫金大桥为工程背景,进行了全过程监控;同时以神经网络技术为基础,对影响斜拉桥线形的各种参数进行参数的识别及主梁标高的预测,主要完成以下几项内容:1.详细制定了施工监控内容及方案,以此来合理、安全的指导施工全过程;2.对承台及下横梁大体积混凝土水化热进行监控并采取了相应的措施防止发生温度裂缝;3.在索塔施工中,采用横向钢管主动支撑法对中塔柱塔脚处的应力进行控制,保证了索塔施工的顺利完成;4.运用神经网络BP算法对主梁的混凝土弹性模量和容重进行实时识别,并通过实测值验证了其可靠性,利用此算法对后续施工进行了相应的预测;5.制定合拢方案并对成桥线形及索力进行调整。更多还原

【Abstract】 Cable-stayed bridge is high hyperstatic structure having stringent requirements on the Linear of bridge.The change of coordinates of each node can affect the distribution of structure’s internal forces. Once the Linear of bridge deviates from the design value, internal forces will deviate too.Therefore, we must strictly control the construction process of the cable-stayed bridge in order to ensure a reasonable linear of bridge. In this paper, Zijin Lishui Bridge is used for example and execute the entire monitoring of the cable-stayed bridge’s construction. At the same time, based on neural network technology, express various parameters of impact the linear of cable-stayed bridge, and identificate each parameter, forecast the main beam elevation. The main contents are as follows:1. Formulate the content and program of construction monitoring elaboratly,as a means of guiding the entire process of construction reasonably and safly,2. Monitor the heat of hydration of mass concrete of the cap and the under-beam, and corresponding measures have been taken to prevent the occurrence of temperature cracking,3. In the construction of the tower ,control the stresses of foot tower in the mid-tower using the means of horizontal steel’support,4. Insure real-time identification of the concrete elastic modulus and density of main beam by BP neural network algorithm, and verify its reliability through the measured values,and forecast the follow-up construction using this algorithm,5. Formulate the close up the program and adjust the linear and the cable force of the builted bridge.更多还原