Stabilized clay-gypsum binder

Abstract

Clay gypsum is a natural sedimentary rock of chemical origin, containing from 50 to 95% of fine-grained crystalline gypsum, evenly distributed between clay minerals. The purpose of the research was to develop the compositions of the stabilized clay-gypsum binder, taking into account the temperature regimes of its firing. The studies were based on mathematical planning of the experiment with subsequent statistical processing of the results and obtaining polynomials that adequately describe the phenomena under study and with analytical optimization of these polynomials. It has been established that the optimal firing temperature of the initial sedimentary rock is 294–295 °C. The strength of the clay-gypsum binder is 8.8–8.6 MPa, which corresponds to the G-8 grade gypsum binder. The introduction of a superplasticizer additive makes it possible to increase the strength of the binder by 10–20%. As a result of the research, the technological parameters for obtaining a clay-gypsum binder, the modes of its heat treatment (roasting) were optimized, and the influence of technologies on the properties of the clay-gypsum binder, which can be considered as an analogue of a binder obtained from natural gypsum raw materials, was studied.

Hydrophobized clay gypsum

“…Clay gypsum has a number of advantages over plastering and molding gypsum, namely: clay gypsum plaster is smooth, without pores, has a pleasant texture, is durable and is not afraid of water; working with it is more convenient -setting begins more slowly than with gypsum. The mechanical strength is very significant and has better results than molding gypsum when mixed for sculptural castings [10,11].…”