ANALYSIS OF THE VIBRATIONS OF INFLATABLE DAMS UNDER OVERFLOW CONDITIONS

A two-dimensional analysis is applied to the vibrations of inflatable darns under overflow conditions. The cylindrical membrane dam is inext ensible, air-inflated and anchored along two generators. The base widt h, curved perimeter and internal air pressure are given. The flow is i ncompressible, inviscid and irrotational, and the total head is specif ied, In the steady-state analysis, the equations of equilibrium of the dam from membrane theory are solved by a multiple shooting method, an d the boundary element method is used to solve Laplace's equation defi ned on the overflow domain, An iterative scheme is adopted to obtain t he shapes of the dam and the free surface of the fluid. Then the dynam ic analysis is established by a finite difference form of the membrane 's equations of motion, and the velocity potential problem is formulat ed by the boundary element method. The eigenvalues and eigenvectors ob tained ave employed to describe the small vibrations of the dam. The e ffects of the dam's density and damping coefficient on the stability a nd response of the clam are investigated. Copyright (C) 1996 Elsevier Science Ltd.