Viscous Damping and Contraction Joint Friction in Underwater Explosion Resistant Design of Arch Dams

AbstractThe aim of this study is to clarify the parameter-determination issue with regard to the viscous damping and contraction joint friction in the underwater explosion (UNDEX) resistant design of arch dams. A 141-m-high double-curvature arch dam is chosen as the study subject, and the finite-element program ABAQUS/Explicit is employed. Both the dam-reservoir interaction and the contraction-joint nonlinearity are considered. The calculation results suggest that in a routine range of values for the viscous damping ratio (less than 0.05), the damping effect on the UNDEX-induced displacement and damage responses of the arch dam seem limited. To be conservative in the design, the viscous damping ratio could be assigned a zero value (neglecting the damping effect). The calculation results have highlighted the importance of the monolith-to-monolith friction to the tensile damage to the dam base. We believe that a value of 0.65 assigned to the friction coefficient should be appropriate for the UNDEX resistant design of an arch dam in case the shear keys’ shear-transferring roles are not considered.