In this paper, we consider the boundary stabilization of a
sandwich beam which consists of two outer stiff layers and a
compliant middle layer. Using Riesz basis approach, we show that
there is a sequence of generalized eigenfunctions, which forms a
Riesz basis in the state space. As a consequence, the
spectrum-determined growth condition as well as the exponential
stability of the closed-loop system are concluded. Finally, the
well-posedness and regularity in the sense of Salamon-Weiss class
as well as the exact controllability are also addressed.