Expertimental study on the contribution of fibers on the punching shear capacity of plain ECC slabs

This study aims at investigating the influence of fibers on the punching shear capacity of plain ECC slabs.An experimental investigation was conducted on the punching shear resistance of plain ECC slabs with varying fiber volume fractions (FVFs).A total of sixteen plain ECC slabs were cast and tested, each with dimensions of 300 mm in side length and 40 mm in thickness.All slabs were simply supported on a bespoke steel framework with eight supports and concentrically loaded through a circular steel column stub with dimensions of 66 mm in diameter and 30 mm in height.The experimental results revealed that the plain ECC slabs with FVFs of 1.0%, 1.5% and 2.0% were characterized by punching shear failure, while slabs featuring 0.5% FVF were governed by flexural failure.It can be concluded that increasing FVF enhances the flexural capacity of plain ECC slabs more significantly than their punching shear capacity.Moreover, increasing the fiber volume fraction resulted in an increase in both crack resistance and ultimate load-carrying capacity.Notably, the punching shear capacity of plain ECC slabs increased almost linearly with increasing fiber volume fractions.