The Research On Continuous Steel-Concrete Composite Beams' Crack Width Calculation And Reasonable Section

Now days, the composite steel-concrete beam, as a kind of important transversebending component of composite structure, which holds merits of the steel structureand the concrete structure, has been widely used in the filed of the building and thebridge resulting in remarkable social and economic profitability. However, with thefurther application of the composite steel-concrete continuous beams, some problemsare becoming more and more distinct,like cracking of concrete in the negativemoment region leading to lower section stiffness. Therefore, the scientific scholarsboth at home and abroad have been carried series of research work since the 1960s,with some defects still remaining unresolved.The objects of this research are: (1) to analyze the course of the crack, itsappearing and development, and discuss the major factors influencing the behavior ofthe negative moment region in continuous composite beam. (2) to establish the modeand formulas of the crack width by the theoretical analysis. (3) to discuss thereasonable section shape of the continuous composite beam. The works of this paperare as follows:(1) Contrast the cracking course of the concrete beam and the composite beam, atthe point of the bending state of the beams, put forward the crack width mode:bending curvature,crack height,the distance between crack.(2) Base on the crack width mode ,separately establish formula of the bendingcurvature,crack height,the distance between crack, and compost the formula of thecrack width. And put the experiment data of others literature into the formula, thecalculated result also show good agreement with the experiment data.(3) It is known that load effect is not consistent with the section resistance incommon section continuous composite beam. A kind of composite beam with itsrational section size is suggested, which is consist of the T shape concrete beam andsteel girder. This kind of composite beam not only has enough carrying capacity,almost has same positive and negative resistance moment, but can decrease theamount of the steel.(4) Using the Finite Element Software ANSYS simulate the carrying capacity ofthis kind composite beam and achieve nice result, which prove the kind of composite...