Experimental Study On Shear Performance And Design Methods Of Prefabricated Steel Reinforced Concrete(PSRC) Beam Under Hogging Bending Moment

Prefabricated steel reinforced concrete beam(abbreviated as PSRC beam)is a new kind of steel reinforced concrete(always abbreviates as SRC) composite beam, and is composed of half-prefabricated concrete part and half-fresh concrete part. Because the outside half-prefabricated concrete part of this PSRC beam was fabricated in shop before in-site construction, and had enough share capacity as well as big flexure rigidity,lots of in-site work such as rein bars, frameworks and scaffoldings could be avoided. All these will induce lots of advantages such as convenient construction, flexible design,low cost, better construction quality, which are very important and attractive for structural contractors who always care about the construction time and cost. In this paper, the shear performance including shear capacity, flexure rigidity, deformation of PSRC Tee shape beams under hogging bending moment was fully studied, with a series of static tests of 6 PSRC beam specimens. And furthermore, based on the results, a set of design procedure including calculation methods of shear capacity and flexure rigidity of PSRC beam under hogging bending moment was founded and presented.Experiments of 6 Tee shape PSRC beams specimens were conducted to study shear performance of PSRC beam under hogging bending moment, especially the influences of two key variables-fresh concrete compression strength and shear span ratio- were fully focused on. In which the specimens were loaded statically at one load-point, and the influence of key variables such as concrete strength and shear span ratio.on shear performance were focused on. And the strains of concrete, steel shapes, reinforced bars and the deformations of the specimens were record, and the failure pattern and cracking modes, shear capacity, deformation, ductility of all beams specimens were observed andanalyzed. Seen from the experimental results, it could be concluded that the shear capacity of PSRC beam under hogging bending moment was very similar to the fully cast-in-place SRC beam, and the composition action was fully developed because no visible slippages on the interfaces between steel shape and concrete and between the precast concrete and fresh concrete were observed.Based on the experimental results, a set of calculation formula of shear capacity of PSRC Tee shape beam under hogging bending moment was founded and proposed with refer to now-existing procedures and calculation methods, and the proposed methods were verified by the comparisons between the experimental and calculation results.Furthermore, the calculation formula of flexure rigidity of PSRC beam was also derived based on some theories of SRC beam, and based on these formula the short term deflections were calculated and were in good agreement with the experimental results.Together with the research on shear performance of PSRC beam under hogging bending moment, a set of calculation methods of shear capacity and flexure rigidity of PSRC beam under hogging bending moment were also founded and proposed. All the above research will be very helpful for the application of this new kind of beam.