High content phosphogypsum-based curbs: Mechanical properties, freeze-thaw resistance, carbon reduction and creative theory application

Abstract

Phosphogypsum poses significant environmental pollution risks when stockpiled in large quantities. Given the current problems in the use of phosphogypsum, this study takes phosphogypsum as the research object, modifies phosphogypsum by triethanolamine (TEA), and investigates how curbstone mechanical properties and anti-freezing performance are affected by phosphogypsum and the micro-mechanisms. Then calculates carbon emission reductions in phosphogypsum production and curbstone preparation. Results indicate that increasing TEA doping initially enhances the mechanical performance of phosphogypsum curbstones. Hydration product formation follows a similar trend. Compressive strength tests reveal an optimal rate of 30% phosphogypsum substitution, achieving 31.4 MPa, meeting Concrete Curbstone standards (JC/T 899-2016). Freeze-thaw experiments show minimal mass loss, with strength retention lowest at 30% substitution (16.8%). Carbon emission calculations show the carbon emission of phosphogypsum is less than that of natural sand and cement. Analysis of phosphogypsum and curbstone trends underscores its growing prominence in cementitious material research compared to fly ash and slag. In addition, this paper presents a conceptual design of a phosphogypsum-based curb stone intended to prevent vehicles from veering off the road. These findings guide phosphogypsum utilization in curbstone applications and provide foundational support for carbon emission reduction strategies replacing silicate cement with modified phosphogypsum.