The complex stiffness matrix and th, mass matrix of a uniaxial bar sub
jected to constrained layer damping over its entire length are derived
exactly by solving the differential equations of motion of the three-
layered structure. The stiffness and mass matrices of a bar with segme
nted damping treatments are obtained by assembling the corresponding m
atrices for each segment and eliminating the internal nodes using a re
duction procedure similar to static condensation. The natural frequenc
ies, mode shapes, and loss factor of a pin-connected truss containing
several damped members are computed by three different methods: truss
finite element (TFE) method (exact), equivalent beam element (EBE) met
hod, and scaled beam element (SBE) method, each method being more effi
cient than the preceding one. A 10-bay plane truss is considered as an
example to illustrate each method. The EBE method yields very good re
sults, but the savings in computation is not significant. The SBE meth
od reduces the computational effort drastically and gives reasonably a
pproximate results.