Experimental Study And Mechanical Behaviour Analysis On Pre-stressed Cantilever Composite Beam With Corrugated Steel Webs

As a new style of structure, steel-concrete composite spine girder with large cantilever beams has been more and more applied for its advantages such as beauteous build,outstanding mechanics and economical performance. However, the cantilever beam's concrete deck of this structure will be cracked easily at the negative moment region. Therefore, how we prevent the concrete deck from cracking to improve its durability is a problem needed to solve. In this thesis, the new structure of pre-stressed cantilever composite beam with corrugated steel webs on steel-concrete composite spine girder was brought forward for the first time, a series of experimental researches and theoretical analyses relating to this new structure are conducted, including load transverse distribution rule, shrinkage and creep effect, temperature difference effect, and ultimate bearing capacity. The main work is described as follows:(1) This thesis introduces the phylogeny, research and application actuality inland and abroad of steel-concrete composite structure with corrugated steel webs, summarizes the basic construction and forcing characteristic of pre-stressed cantilever composite beam with corrugated steel webs.(2) Based on the existing theory of lateral load distribution rule, and combined the structure characteristic of pre-stressed lager cantilever composite beam with corrugated steel webs, this thesis proposed the modified rigid beam method. Taking this method, it is facilitated to compute the lateral load distribution factor of bearing composite cantilever beam with variable-stiffness under the load in arbitrarily position. Through the experimental research, an instance of a real bridge and spatial finite element analysis, it is proved that the modified theoretical calculation is valid and accurate.(3) This thesis deduces the predigestion calculating method for calculating the section stress redistributed by the effects of concrete shrinkage, creep and difference temperature of pre-stressed lager cantilever composite beam with corrugated steel webs. Through the theoretical calculation and parameter analysis and compared the result with general composite beam, the results show that the section stress redistributed by the effects of concrete shrinkage and creep and tensile stress by difference temperature will be greatly reduced. The forcing characteristic of this...