摘要
通过实地调研与取样分析,研究、分析了鼓浪屿民国时期历史建筑混凝土构件劣化的现状,从混凝土的原材料、配合比设计、施工质量和外部环境等多角度深入探讨了劣化的原因.研究发现:露筋锈蚀、混凝土性能退化、构件开裂渗水是鼓浪屿历史建筑混凝土构件劣化的宏观表现.劣化混凝土的微观表现为骨料表面仅附着少量水泥浆体,骨料与水泥界面连接疏松,砂浆内部存在较多的孔隙;样品中含有较多的CaCO_(3)、较少的水化硅酸钙及少量的Ca(OH)_(2),同时伴有少量的CaSO_(4)·2H_(2)O、高硫型水化硫铝酸钙(Aft)与单硫型水化硫铝酸钙(Afm)及微生物细菌.样品的pH值均小于9,热重分析仅出现CaCO_(3)的分解峰,证实混凝土碳化严重.混凝土原材料性能存在缺陷,配合比多凭经验而非科学设计,施工质量较差,以及CO_(2)、海风与盐雾、酸雨、微生物等多重环境介质交互侵蚀,共同加剧了鼓浪屿历史建筑混凝土构件的劣化.
Through field investigations and sampling analyses,the deterioration status of concrete components for historic building in Gulangyu of China,is studied.Reasons for the deterioration are explored in terms of four perspectives,namely concrete raw materials,mix design,construction quality,and external environment.We have found that exposed bar rust,concrete performance degradation,as well as component cracking and water seepage constitute macroscopic manifestations of the deterioration of concrete components in Gulangyu historic buildings.Regarding the microscopic performance of degraded concrete,only a small amount of cement paste is attached to the surface of the aggregate.The interface between the aggregate and the cement is loose,and plenty of pores exist in the mortar.Furthermore,the degraded concrete contains more CaCO_(3),less C-S-H and a small amount of Ca(OH)_(2),accompanied by a small amount of CaSO_(4)·2H_(2)O,Aft and Afm,and microorganisms.Moreover,pH values of the samples decrease to less than 9,and only the decomposition peak of CaCO_(3) appears in thermogravimetric analysis,indicating the high degree of carbonation.The concrete raw material performance endures defects,whereas the mix ratio is more based on experiences rather than scientific designs.Finally,the inferior construction quality,the interactive erosion of multiple environmental media such as carbon dioxide,sea breeze,salt spray,acid rain,and microorganisms among others,have jointly aggravated the deterioration of the concrete components in Gulangyu historic buildings.
作者
胡红梅
朱杰
刘涛
石建光
谢益人
HU Hongmei;ZHU Jie;LIU Tao;SHI Jianguang;XIE Yiren(College of Architecture and Civil Engineering,Xiamen University,Xiamen 361005,China;Xiamen Helidao Engineering Design Group Co.Ltd.,Xiamen 361005,China)
出处
《厦门大学学报（自然科学版）》
CAS
CSCD
北大核心
2022年第2期298-307,共10页
Journal of Xiamen University：Natural Science
关键词
鼓浪屿
历史建筑
混凝土构件
劣化现状
Gulangyu
historic building
concrete component
deterioration status
