Pervious concrete with secondarily recycled low-quality brick-concrete demolition residue: Engineering performances, multi-scale/phase structure and sustainability

Brick-concrete demolition residue after the primary recycling is generally discarded due to its low quality. Secondary of brick-concrete urgently required be solved at present in China large scale constructions and demolitions, remains a challenging task. In this work, from an urban-fringe Hangzhou, China, was secondarily recycled as fine aggregate fabricate sustainable pervious concrete systematic characterization physical chemical properties. order improve engineering properties concrete, natural sand were used. Multi-scale structure terms pore size distribution, skeleton morphology, matrix-aggregate interfacial transition zone systematically characterized using X-ray computed tomography backscattered electron imaging tests. Results show that increase replacement ratio always increases compressive strength density, but decrease water permeability. Incorporation secondary total porosity connected helps form Calcium-enriched layer zone. Use manufacture optimal mix brings CO2 emissions reduction by 107 kg/m3 costs 30.3 USD/m3. The findings work provide route recycle low-quality for constructions.