Study on inspection and recycling evaluation of stone masonry of old Kada dam after 46 years service

Abstract

Stone masonry structure has been widely utilized in dam construction due to its low cost and easy operation. However, its long-term durability has also been raised wide concern. Based on the demolition of the Kada dam, this study investigated whether the durability of block stones and mortar in the stone masonry dams can be guaranteed under the influence of combined factors, such as freeze-thaw cycles, water seepage, and high-velocity erosion. Through a combination of on-site sampling and laboratory testing, the physical properties, mechanical performance, composition, and pore characteristics of the block stones and mortar, predominantly composed of limestone, were thoroughly examined and evaluated. The results indicate that both the crest and center block stones exhibit a dense structure, with a saturated compressive strength exceeding 50 MPa, meeting the strength requirements for the reconstruction of new buried concrete gravity dams, which could supply sound foundation for the reuse and recycling during reconstruction of the dam.

Keywords

• Stone masonry
• Kada dam
• Physical properties
• Durability
• Recycling evaluation