Mathematical Models of the Dependence of the Structural and Deformation-Strength Properties of the Gypsum-Wood Composite on the Component Composition

Abstract

The production of cement-wood composites (CWC) is difficult due to the presence of extractable substances in the wood filler, which have a negative effect on the hydration of cement, the shape and size of the resulting crystalline hydrates, and the setting time, which leads to a decrease in the strength characteristics of the CWC. Gypsum-wood composites (GWC), in contrast to CWC, are less sensitive to the effects of extractable substances, but they are characterized by low strength and deformability. In order to improve the structural and deformation-strength properties of the GWC, the article presents a mathematical modeling of the effect of the component composition on the average density, open porosity, compressive strength and modulus of elasticity of a gypsum-wood composite for the installation of partitions and enclosing structures in buildings for various purposes. Mathematical models of the dependence of GWC properties on the amount of building gypsum, urea-formaldehyde resin and wood filler from freshly cut hardwood are presented. According to Student's and Fisher's criteria, an assessment was made of the statistical significance and adequacy of the obtained mathematical models, which make it possible to determine the rational values of recipe factors in the manufacture and operation of GWC with an average density of 1250-1370 kg/m3, an open porosity of 25-36%, and a compressive strength of 25-30 MPa, modulus of elasticity 1210-1780 MPa.