On the coefficient of linear thermal expansion of wet masonry at freezing temperatures

Introduction. Stone masonry is a structurally heterogeneous (composite) material; therefore, a number of its physical and mechanical characteristics are orthotropic, including the coefficient of linear thermal expansion. The article analyses the coefficient of linear thermal expansion of stone masonry under the conditions of its operation in different temperature and climatic conditions, including different humidity. Aim. To obtain the dependence of the coefficient of linear thermal expansion on masonry humidity at freezing temperatures by comparing the results of studies of wet masonry samples. Materials and methods . The study is based on the data of M.A. Mury published in his work "Temperature deformations of wet brickwork" and some of his previously unpublished data. Regression analysis was used to perform the research. Results. There were obtained graphical and mathematical dependences of the coefficient of thermal expansion of masonry in the form of piecewise linear functions at freezing temperatures, with account of material humidity. Conclusions. The presented dependences can be used in calculations of the stress-strain state of masonry structures with the use of modern program complexes. Published data on the coefficient of linear thermal expansion of masonry show a wide range of their values, which indicates fragmentary research based on the use of ceramic stones from a single manufacturer. Therefore, large-scale research with systematization of the results with a logically justified maximum number of varying parameters of masonry should be carried out, with subsequent amendments to the norms of design and construction of masonry structures based on the results of the research.