Preparation and performance of pervious concrete with wood tar-formaldehyde-modified epoxy resins

Pervious concrete made from epoxy resin suffers from high cost and is prone to cracking due to its inherent brittleness and aging. In this study, wood tar and formaldehyde, both easily available and low in cost, were used to modify epoxy resins via Mannich reaction. The resultant water from the reaction could facilitate cement hydration to form better adhesion with coarse aggregates as framework. Pervious concrete with modified epoxy resins demonstrated 21.9% improved compressive strength and 52.5% increased abrasion resistance, with comparable aging and frost resistance performance. The enhancing mechanism of modified epoxy resin was investigated by FTIR spectroscopy, DSC, and NMR analyses.