Analysis Of The Causes Of Glazed Tile Diseases And Research On Protection Methods

As a component of ancient buildings,glazed tile is often used for roof and wall roof to decorate,protect and waterproof.In this study,temperature,humidity and acid rain corrosion of glazed tile were simulated,and the damage process of glazed tile under the influence of external temperature,moisture and acid rain was explained by characterizing morphological changes and corrosion products.The main conclusions of this study are as follows.(1)Extreme high temperature,low temperature and rapid temperature change have little effect on glazed tiles.Moisture is an important environmental factor for the deterioration of glazed tiles.The repeated effects of sudden rainstorms during high temperature in summer mainly cause damage to the edge of glazed tiles.The freeze-thaw cycle of water in winter mainly causes the glaze cracks of glazed tiles to widen and fall off,matrix cracks and fractures;the inconsistency of thermal expansion coefficient and water absorption between glaze layer and matrix is an important internal cause of its damage.(2)The synergistic effect of Cu and Pb in the green glaze accelerates the loss of Cu and Pb under acidic conditions,so the corrosion phenomenon is more serious than that of the yellow glaze.There is a significant fading silicon-rich layer on the surface after the loss of Cu and Pb elements.The yellow glaze generates a small amount of lead sulfate particles under the condition of p H = 1,which accumulates at the crack,and there is no obvious corrosion phenomenon under the condition of p H = 3.The corrosion product lead sulfate covering layer was formed on the surface of green glaze at p H = 1and p H = 3,and the regular polyhedron lead sulfate was formed at p H = 1,which was not found at p H = 3.(3)When the addition amount of PDMS-OH was 15% and the addition amount of ethanol was 10%,the reinforcement and water resistance of PDMS-OH/TEOS were the best.The addition of ethanol can reduce the surface color difference and improve the permeability of the reinforcement material.The addition of PDMS-OH/TEOS filled the internal pores of glazed tiles and improved the density of the matrix.The introduction of organic groups made the surface of the matrix hydrophobic.Part of the inorganic network produced by the hydrolysis of TEOS copolymerized with the terminal hydroxyl groups of PDMS-OH to form Si-O-Si bonds,which filled in the pores to increase its strength.(4)The change of the particle size of the matrix of glazed tile does not affect the element composition and phase structure after firing,and the mechanical properties,water resistance,density and weathering resistance of the matrix can be greatly improved when the particle size is less than 0.15 mm.The properties of the matrix of glazed tile with the particle size ranging from0.15 mm to 0.25 mm are improved slightly but the matrix cracks are greatly reduced.The large particle with the particle size > 0.25 mm after firing seriously affect the color rendering of glazed tile and the performance of the matrix is significantly decreased.