METHOD OF ASSESSMENT OF COMPARATIVE crack resistance of plaster MINERAL COMPOSITION

摘要

1. A method of evaluating crack resistance comparative plaster based on mineral compositions, test samples comprising a plaster material composition, characterized in that on the degreased metal plates applied plaster material layers of equal thickness, they stand under normal conditions at a temperature of 20 ± 2 ° C, humidity 90 ± 5% for the time required to set plaster composition strength after a period of storage in normal samples continue to be stored in a climatic chamber at the humidity and temperature, are close to the natural conditions of use of the materials, and conduct visual observation of the process of crack formation, wherein for fracture toughness test taking time from start of observations up to the start of the crack, followed by a comparative analysis of the test plaster materials and assess the degree of shrinkage cracking each materiala.2. . A method according to claim 1, wherein the plate coverage layer of plaster material is removed from the plate edges at a distance 5 4 ... δ, where δ - thickness of the plaster layer, which allows to consider the work of the plaster layer in actual use.