返碱引起的内墙砖膨胀开裂问题案例分析  

Case Study of Internal Wall Ceramic Tile Swelling and Cracking Caused by Efflorescence

作　　者：李保亮 唐洲洋 陆雪 孙民辉 丁百湛 

机构地区：[1]淮阴工学院建筑工程学院,江苏淮安223001 [2]淮安市建筑工程质量检测中心有限公司,江苏淮安223001

出　　处：《混凝土世界》2022年第8期48-52,共5页China Concrete

基　　金：江苏省建设系统科技项目(2020ZD85、2021ZD74);2021年大学生创新创业训练计划项目(202111049005Z)。

摘　　要：结合2个典型的因返碱引起的内墙面砖膨胀开裂的案例,对工程返碱的特点、影响因素进行了分析;并采用XRF、XRD、SEM-EDS分析了返碱产生的白色粉末的化学组成、矿物组成、微观形貌。结果表明:白色粉末的主要化学组成为SO_(3)、Na_(2)O、K_(2)O、CaO等,主要矿物组成为Na_(2)SO_(4)、K_(3)Na(SO_(4))_(2)、Na_(2)CO_(3)·3NaHCO_(3)、KHCO_(3)、CaCO_(3)等,其形貌主要为类椭圆球体;墙体返碱的主要原因是建材中的Na_(2)SO_(4)、Na_(2)CO_(3)、K_(2)CO_(3)、K_(2)SO_(4)、Ca(OH)_(2)(或CaO)含量超标,而Na_(2)SO_(4)、Na_(2)CO_(3)、K_(2)CO_(3)等吸水、结晶、膨胀是造成内墙砖开裂的主要原因。Combined with two typical cases of internal wall ceramic tile swelling and cracking caused by efflorescence,the characteristics and influencing factors of efflorescence were first analyzed.Then,XRF,XRD and SEM-EDS were used to analyze the chemical composition,mineral composition and morphology of the white powder caused by efflorescence.The results show that,the main chemical composition of white powder is SO_(3),Na_(2)O,K_(2)O and CaO,the main mineral composition is Na_(2)SO_(4),K_(3)Na(SO_(4))_(2),Na_(2)CO_(3)·3NaHCO_(3),KHCO_(3),CaCO_(3),etc.,the morphology is mainly elliptic sphere.The content of Na_(2)SO_(4),Na_(2)CO_(3),K_(2)CO_(3),K_(2)SO_(4),Ca(OH)_(2)(or CaO)in building materials exceeds the standard is the main reason for efflorescence,while the water absorption,crystallization and expansion of Na_(2)SO_(4),Na_(2)CO_(3)and K_(2)CO_(3)in construction materials are the main reasons for internal wall ceramic tile swelling and cracking.

关 键 词：返碱 内墙砖 开裂 案例分析 

分 类 号：TU754[建筑科学—建筑技术科学]