非洲某近百年历史的旧码头混凝土性能分析

Concrete performance of an old wharf with history of nearly a century in Africa

非洲某海港重力式方块码头建于1928年,1950年进行扩建,1968年进行修复时将上部胸墙混凝土拆除并重建钢筋混凝土。从始建至今将近百年,结构破损严重。根据勘察报告揭示不同时期混凝土的性状,描述不同时期混凝土结构的强度、孔隙率、裂缝发展程度等特点,并分析其原因,包括建设时混凝土技术水平,施工的专业化、机械化程度,码头环境条件,使用年限和运营情况,码头防护设施的设置情况,以及在码头运营期间的历史背景等。其中,码头结构建设时的混凝土发展水平、原材料选择、浇筑质量是影响旧码头混凝土性能的根本原因,而混凝土在高酸、高盐的海水环境中受到长期溶蚀,是影响混凝土性能的主要原因。通过混凝土特点和原因分析,为修复方案的确定、修复工作的顺利开展提供依据,以及为类似码头改造工程提供借鉴。

A gravity block wharf of a seaport in Africa was built in 1928 and expanded in 1950.During the restoration in 1968,the concrete breast wall was removed and reinforced concrete was rebuilt.Nearly a century since its establishment,the structure has suffered severe damage.According to the survey report,the characteristics of concrete in different periods are revealed,the strength,porosity,crack degree and other characteristics of concrete structure in different periods are described.The reasons for this are analyzed,including the level of concrete technology during construction,the degree of specialization and mechanization in construction,environmental conditions of the wharf,service life and operational status,the setting of wharf protective facilities,as well as the historical background during the operation.Among them,the development level of concrete,selection of raw materials and quality of pouring during the construction are fundamental reasons that affect the performance of concrete in the old wharf,while the main reason is long-term corrosion in high acid and high salt seawater environments.By analyzing the characteristics of concrete,this study provides a basis for the determination of repair plans and the smooth implementation of repair work,and provides references for similar wharf renovation projects.