Prestressed Composite Beam Inclined Section Shear Performance Analysis And Calculation Method Is Discussed

It is different from general integral casting of concrete beams that prestressed concrete composite beams have its own characteristics which are its secondary cast and two-stage loading, and it mainly shows the phenomenon of’the stress ahead’for the precast concrete and reinforced and’the compression strain hysteresis’for overlapping part of the concrete. In this paper, on the basis of the results which scholars from home and abroad research the force performance of composite beam, it makes a systematic summary in its mechanical behavior, such as failure mechanism of the oblique section, failure patterns, re-distribution of pre-shear stress and factors of shear capacity and so on.By summarizing the results of previous studies it is found that the main factors of influencing prestressed composite beam shear strength are the role of prestress, differences in the strength of concrete, the ratio αh of beam’s height before and after composite, the ratio αM of M, and prefabricated ultimate moment M(?) and the role of stirrups and so on.By using nonlinear finite element software it calculates similarly on prestressed composite beams, composite beams and general integral casting beams and analyses comparatively the simulated structure. By using ANSYS, it applies the full simulation and obtains more vividly the distribution phenomenon of partially precast prestress of prestressed composite beams,’PC Load’distribution, some ’stress ahead’of precast concrete and stirrups, and the feature of’strain hysteresis’of some concrete which is poured after others and so on. By comparative analysis of three beams, it is gotten that external prestress can alleviate the’stress ahead’of composite beams to some extent.Based on the previous study of the formula of shear capacity of prestressed composite beam, using ANSYS finite element method, it simulates35prestressed composite beams,5general composite beams and2general integral casting beams, based on the numerical simulation, by the use of mathematical methods it analyses the effects on the composite beam shear capacity which is caused by prestress, concrete strength, stirrup’s function and composite parameters (αh、αM).Combined with the existing formula in the Specification, it proposes the shear capacity formula taking into account the influence factors of prestress, concrete strength and composite parameters.