Removal of 80-Year-Old Gravity Dam and Mechanical Properties of Aging Dam Concrete

Service life of concrete structures depends on the structure design, construction management, and the durability of concrete in aggressive exposure conditions. The old Fengman Dam is an 80-year-old gravity dam, and due to design and construction defects, it has worked with leakage and freeze-thawing problems for more than 70 years. In this study, the durability of the dam concrete is investigated, and a coring program is conducted. The static and dynamic mechanical properties of aging dam concrete (ADC) are tested and the micropores are also observed by scanning electron microscope. Young laboratory concrete (LC) with similar compression strength of the ADC is prepared for comparison. The experimental results show that despite the harsh working conditions, the ADC exhibits good mechanical characteristics in terms of static and dynamic strength and microporosity of interfacial transition zones. The dam concrete is proved to exhibit good durability, and the service life of old Fengman Dam was limited by the poor construction management.