Stress-strain state of masonry with large ceramic blocks under concentrated loads

Introduction. Special requirements for the calculation of masonry walls using large ceramic blocks with the void content up to 57 %, including under the action of concentrated loads (buckling) are given in SP 15.13330.2020. In particular, Table 7.5 of this SP gives the coefficients for determining the calculated values of masonry under buckling. However, the results of Russian and foreign studies show that the masonry made of blocks with the void content more than 50 % requires clarification of the coefficient values for determining the calculated resistance of masonry buckling. The results of experimental studies conducted at Research Institute of Building Constructions named after V.A. Koucherenko to determine the masonry strength under buckling for clarifying the calculated coefficients presented in SP 15.13330.2020 are given.

Aim. To develop a methodology and specify the transition coefficients for determining the calculated values of the strength of large ceramic block masonry under buckling on the basis of the results of Russian and foreign experimental studies.

Materials and methods. Experimental studies have been carried out to examine the stress-strain state of large ceramic blocks and masonry walls with their use under the action of concentrated loads applied according to the schemes that can be most accurately realized in laboratory conditions, particularly schemes a and e given in paragraph 7.14 of SP 15.13330.2020.

Conclusions. The results of these studies have shown that the buckling strength of large ceramic blocks masonry depends on several factors, including the magnitude of normal and tangential stresses in vertical sections between the compressed zone and the unloaded section of the masonry. In addition, the shell effect in the presence of horizontal joints has a great influence.

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