Study On Cable Tension Optimization Of Cable-stayed Bridge In Segmental Scaffold Construction Method

The construction of the cable-stayed bridge is a continually changing process of its structure system. In order to achieve rational complete bridge state and to ensure the safety of constructing bridge, it must be strict with the construct process, and more various construction methods has brought some new subjects to construction control. This paper discusses the cable tension control of Houhu Cable-stayed Bridge, combining with the character of segmental scaffold construction method.Firstly, a cable tension calculation model is established in which the most and the least stress of the normal load is defined as target function, with main beam moments as constraint condition and cable tension as optimization variable. Considering the requirements of uniform of the cable tension, the bending of the tower and the resistance of the side and assistant piers, we make out the optimization model and then attain a reasonable cable tension of Houhu Cable-stayed Bridge.Secondly, a finished state is obtained with forward-calculation by presuming the controlling cable tension. And then compare it with design finished state, a new state is calculated by the optimization model of cable tension during construction, iterate the aforesaid procedure until the value is constringed, which attained a reasonable construction cable tension of Houhu Cable-stayed Bridge.Meanwhile, according to the construction demand of the Houhu Cable-stayed bridge, and make full use of the character of segmental scaffold construction method, this article brings forward the twice stretching method for the cable tension controlled method. Taking the fifty percent and hundred percent of the initial cable tension as control cable tension, the firstly cable is tensioned. The secondly tension is realized after joining the two sections of a bridge. This ensures the structure of reasonable tension and safety.Lastly, this paper detail analyses the affect factors of the frequency method to measure the cable tension, and correct these factors. The analyzed guarantee the precision of the frequency method to measure the cable tension.Study on the cable tension control of the cable-stayed bridge in segmental scaffold construction method, which not only improves technical level of cable-stayed bridge construction control but also solves difficult issues of the cable tension control of the cable-stayed bridge constructed in segmental scaffold construction, meanwhile this paper also offers valuable experience for similar bridge construction in future.