Sustainable ecological pervious concrete (SEPC) based on modified corn-cob coarse aggregate: Crushing morphology, strength, pore properties, and durability

Abstract

In terms of agricultural products, corn is the most abundant crop in the world, yet a significant portion of its cobs are thrown away each year, which is a terrible resource waste. This study uses modified corn-cob coarse aggregate (MCCA) and recycled aggregate (RA) to prepare sustainable ecological pervious concrete (SEPC). Five different substitution rates (0%, 25%, 50%, 75%, and 100%) are designed to investigate the effect of substitution rate on the crushing morphology, strength, pore properties, and durability of SEPC. The results show that the saturated water absorption of MCCA is 45.4% and its numerical tube pressure reaches 0.9 MPa. The test results show that the mix of MCCA reduces the compressive strength of SEPC but is beneficial to improve the stress state of SEPC by increasing its continuous porosity, planting opening size, frost resistance and resistance to sulfate erosion. At 50% replacement rate, comprehensive performance of SEPC is at its best. Specifically, test group with 50% MCCA substitution rate exhibits the lowest rate of compressive strength loss during freeze-thaw cycles (7.58%) and the best corrosion resistance coefficient (97.97%) when subjected to sulfate erosion. Therefore, MCCA can be used as a sustainable and ecological lightweight aggregate to improve some properties of pervious concrete.