Study on the optimization of the mechanica properties of engineered desulfurization gypsum composites using response surface methodology

Abstract

Practical applications of desulfurization gypsum are limited owing to its brittleness and low strength. To overcome these challenges, researchers have developed engineered desulfurization gypsum composites (EDGCs) by incorporating ultrahigh molecular weight polyethylene (UHMWPE) fiber and sulfoaluminate cement (SAC). The mix ratio was optimized using response surface methodology (RSM). Experimental testing of EDGC under compressive and tensile loads led to the creation of a regression model that investigates the influence of variables and their interactions on the material’s compressive and tensile strengths. Additionally, microscopic morphology and hydration product composition were analyzed to explore the influence mechanism. The results indicated that EDGC’s compressive strength increased by up to 38.4% owing to a decreased water-binder ratio and higher SAC content. Similarly, tensile strength increased by up to 38.6% owing to increased SAC and fiber content. Moreover, EDGC demonstrated excellent strain-hardening behavior and multiple cracking characteristics, achieving a maximum tensile strain of nearly 3%. The research findings provide valuable insights for optimizing the performance of desulfurization gypsum.