Research On The Ability Of Shear Resistance Of RC Beam With Different Stirrup Ratio In High Temperature

Various properties of building materials will change under high temperature environment,and the research conclusions under normal temperature conditions are often not applicable to high temperature.At present,the research on fire resistance of RC beams by domestic and foreign scholars is mostly limited to the theoretical analysis and experimental research on the flexural bearing capacity.So the shear resistance experiments of RC beam with different stirrup ratio in high temperature and after high temperature are carried out,and the specific research contents are as follows:1)the shear behavior of 3 full-length reinforced concrete simply supported beams with different stirrup spacing(150,200 mm and 300mm)was tested under fire.The temperature distribution along the section,steel temperature,horizontal and vertical deflection and the fire resistance limit of the beams were obtained during the fire.The influence of different stirrup ratio on the shear performance of reinforced concrete simply supported beams under fire was studied.2)the shear performance of 6 full-length reinforced concrete simply supported beams with different stirrup spacing was tested after fire.The load deflection curve,residual shear bearing capacity,residual stiffness and failure mode of the beams were obtained.The influence of different stirrup ratio,fire duration and cooling mode on the shear performance of reinforced concrete simply supported beams after fire was studied.The results show that:the shear strength of RC beams at high temperature increases with the increase of stirrup ratio;the residual shear capacity of RC beam after fire decreases with the increase of fire time;the residual shear capacity of RC beam after fire is significantly affected by cooling method.The ultimate shear capacity of the test beam with the same parameters obtained by watering is lower than that obtained by natural cooling method;the residual shear capacity of RC beam after fire increases with the increase of hoop ratio.Figure 68;Table10;Reference 42...