Enhancing acid resistance of conventional and desert sand concrete via compression casting for sustainable precast sewer and industrial infrastructure

Cement-based concrete in sewer and industrial structures deteriorates rapidly in acidic environments, shortening service life. This study addresses this problem by investigating the combined effects of desert sand substitution and compression casting technology on acid resistance, mechanical behavior, and microstructural development of concrete. Mixtures with 0–100% desert sand replacement were designed for 30, 50, and 70 MPa and cast under conventional and compression-cast conditions. Sulfuric acid exposure was evaluated through mass loss, compressive strength retention, stress-strain response, scanning electron microscopy, and X-ray diffraction analyses. Results show that conventional desert sand concrete suffers notable acid-induced degradation, whereas compression casting significantly improves density, reduces mass loss, and enhances strength retention, with up to 188% higher residual strength and 52% lower mass loss. The proposed stress-strain model accurately predicts behavior under acid attack. This study provides new scientific insight into the degradation mechanism and offers a sustainable route for durable precast materials in aggressive environments.