Using fibers in porous concrete for strengthen surface drainage structures

In the present research, effect of using fibers in porous concrete used in surface drainage structures was evaluated. The compressive strength (fc) and permeability (k) were measured by adding three different types of fiber including poly-propylene (PPF), macro synthetic (MSF) and cotton (CF) to the porous concrete and testing different lengths (Lf = 1, 3 and 5 cm for MSF and CF and 0.6 and 1.2 cm for PPF) and different volume of fibers (Vf = 1%, 2% and 3% of the weight of cement) at the ages of 7, 28 and 90 days. According to the results, the minimum increment of fc in average at all ages was occurred in porous concrete with Vf = 1% of CF and Lf = 1 cm by about 36%. Moreover, the maximum increment of fc in average at all ages was observed in porous concrete with Vf = 3% of PPF and Lf = 1.2 cm by about 78%. Also, k was decreased up to about 62% by adding fibers to the porous concrete.