Optimization of compressive strength and sound absorption of foamed gypsum-cement composites based on response surface methodology

With the aim of balancing the compressive strength and sound absorption of composite foamed gypsum lightweight materials, a mix proportion optimization method for the materials was proposed in this study. Factors such as the dosage of hydrogen peroxide (H 2 O 2 ), the dosage of white cement, water-to-binder (W/B) ratio, and dilution multiple of animal protein foaming agent were considered, and their effects on the sound absorption average (SAA) and compressive strength were elucidated via the response surface methodology (RSM). Subsequently, a quadratic regression model was constructed to achieve multi-objective optimization of SAA and compressive strength of composite foamed gypsum, and the optimized combinations were experimentally validated. Finally, the pore structure differences of the materials before and after optimization were studied using scanning electron microscopy (SEM) and X-ray computed tomography (X-CT). According to the results, the quadratic polynomial model had a high degree of fitting, demonstrating that RSM could reliably determine the optimal mix proportion parameters for composite foamed gypsum. Through optimization analysis, the optimal values for H 2 O 2 , white cement, W/B, and dilution multiple of animal protein foaming agent were determined to be 2.824 %, 16.522 %, 0.652, and 151.442, respectively, with the SAA and compressive strength of the material being 0.594 and 1.25 MPa, respectively. SEM and X-CT analysis showed that the optimized combination could better optimize the internal pore structure of the material by selecting the mix proportion parameters rationally, thereby achieving a reasonable balance and optimization of sound absorption and compressive strength. • The mechanical properties and sound absorption have been optimized by RSM. • The difference in pore structure before and after optimization was studied using X-CT. • After optimization, the increase in SAA is greater than the decrease in compressive strength.