Effects of steel fibers and mineral filler on the water-tightness of concrete pipes

Water-tightness of concrete and reinforced concrete pipes used to convey sewage flow of any kind is extremely important from the aspects of (1) groundwater contamination and (2) durability of the pipes. In this study, water-tightness tests were applied on plain concrete, reinforced concrete, and steel fiber concrete pipes of 500 mm diameter. Standard seepage tests were applied on many pipes of various materials and combinations with the objective of determining the pipes with the best water-tightness. Tests on plain concrete pipes whose concrete included finely ground limestone passing the no. 100 sieve (d < 0.15 mm) at an amount of 7% by dry weight of the total aggregates revealed that the water-tightness of former was 57% better than that of pipes manufactured without the filler. The water-tightness values measured on steel fiber concrete pipes with a fiber dosage of 25 kg/m3 turned out to be 47% and 15% better than those of plain concrete pipes and reinforced concrete pipes, respectively. Those findings tangibly reveal that the addition of steel fibers and mineral filler in concrete pipes improve their seepage property.