Joint Waterstop Design for 250 m Ultra-high Concrete Face Rockfill Dams in Cold and Seismically Active Regions

Abstract

Deformation control, seismic safety, and durability present significant challenges for 250 m ultra-high concrete face rockfill dams (CFRD) in cold and seismically active regions. These challenges necessitate an elevated standard for waterstop design. Using the 233.5 m high Yulongkashi CFRD as a case study, this paper quantitatively proposes a joint deformation control standard based on the results of 3D static and dynamic finite element analysis, in conjunction with relevant engineering experiences. In addition, a tailored waterstop size design is carried out for different joints. Considering the unique characteristics of the project and dam deformation, factors such as varying stress distribution across the dam face, the impact of freezing in fluctuating water levels, prevention of extrusion failure, and interplate constraints are taken into account. Measures such as multi-channel redundant design, polyurea coating for covering plates, incorporation of seaming materials in vertical joints, and localized reinforcement of compressive joints are employed in the customized design of waterstops for perimeter joints, vertical joints, horizontal joints of the wave wall, and settlement joints. These findings serve as valuable references for similar projects.

Keywords

• CFRD;waterstop design;cold and seismically active region;deformation control standard