多孔烧结陶片在盐溶液中的吸水特性

Water absorbing characteristics of porous firing clay tiles in saline solutions

外墙多孔饰面层在含盐环境下的吸水特性变化,将影响利用被动蒸发技术之低能耗建筑的效能。为探寻盐浓度对陶片吸水特性影响的规律,以一种常用陶片分别在纯水、3.5%及26.3%质量分数NaCl溶液中,采用部分浸泡法进行吸水实验。结果显示:毛细吸水系数在3.5%溶液中比纯水高17.57%,在26.3%溶液中比纯水低12.17%。陶片吸收纯水质量随溶液浓度提高呈线性下降趋势。达到毛细饱和时,陶片含水量在3.5%溶液中比纯水低2.50%,在26.3%溶液中比纯水低16.18%;继续连续吸水24h后,陶片含水量在3.5%溶液中比纯水低3.18%,在26.3%溶液中比纯水低20.51%。综合而言,盐分将削弱陶片吸收纯水的能力,削弱水平随盐分浓度提高而增强,陶片在滨海含盐环境中吸水情况将明显区别于内陆地区。

Water absorption of porous materials were influenced by sea salt.It would lead to changes of the efficiency of the low-energy buildings using passive evaporation cooling technology.To find the relations between the concentration and the water absorption characters,we conducted water absorption tests through partial immersion method with common porous fire-clay tiles and NaCl solution with different concentrations.Compared to the pure water case,tiles' capillary absorption coefficient was higher by17.57%in solutions with the concentration of 3.5% by weight(same below),and lower by 12.17% in26.3% solution.Pure water absorption reduced while concentration increased.Capillary saturated water content was lower in 3.5% solution than in pure water by 2.50%,and lower in 26.3% solution than in pure water by 16.18%.Continuous absorption for 24 hours,the pure water content was lower in 3.5%solution than in pure water by 3.18%,and lower in 26.3% solution than in pure water by 20.51%.Insummary,salts would weaken the water absorption ability of the tiles.The higher the concentration of the solution was,the absorption would be weaker.As a result,water absorption of the tiles in the coastal saline environments would be different from the inland situation.