Mathematical modelling of the ADAS energy dissipation device

Numerical modelling of the added damping and stiffness (ADAS) energy dissipation device is of paramount importance when studying the structural behaviour of buildings with such components. The ADAS devices are special nonprismatic structural elements, therefore, the definition of their stiffness and load-deformation curves using analytical models is not straightforward. Up to now, there is only one approximate method reported in the literature that would allow one to define the elastic stiffness and the load-deformation curve of the ADAS device. This paper presents another method to determine these data. The proposed procedure treats the variation of the cross-section using the flexibility method. Most of the resulting integrals are solved explicitly, closed-form solutions are then available. The proposed expressions were verified against direct derivation and numerical integration solutions. The elastic stiffness and the strength of the ADAS devices computed with the closed-form solutions are compared with those reported in the literature. Predicted hysteresis curves are compared with those obtained experimentally from shaking table tests. (C) 1997 Elsevier Science Ltd.