钢纤维高强混凝土板冲切变形试验

DEFORMATIONS OF STEEL FIBER REINFORCED HIGH-STRENGTH CONCRETE SLABS SUBJECTED TO PUNCHING SHEAR

通过对6块尺寸为1800mm×1800mm×150mm的钢纤维高强混凝土板的冲切试验,对混凝土强度等级和钢纤维体积率对板荷载-挠度曲线的影响进行研究。结果表明,钢筋钢纤维高强混凝土板冲切破坏之前的变形主要是弯曲变形,钢纤维的掺入提高了钢筋混凝土板的初裂荷载、刚度、延性和极限承载力。根据试验结果,引入刚度折减系数反映钢纤维对挠度变化的影响,从而建立适用于从加载到破坏的整个过程中的荷载与挠度的关系式。

Through the punching shear experiments of 6 blocks of steel fiber reinforced high-strength concrete square slabs with the size of 1 800mm × 1 800mm × 150mm, the effect of the concrete intensity and the steel fiber volume on the load-deflection curve are investigated. The results indicate that the deformation of a slab prior to punching shear failure is mainly bending deformation and the mixture of steel fiber hightens the first crack load, rigidity, ductility and limit bearing capacity of reinforced concrete slab. Based on the experiment results, it is introduced the reduction coefficient of rigidity to inflect the effect of steel fiber on deflection varation and it is set up the related formula of load and deflection which is applied to the whole process from loading to destructing.