Lukas MOSCHEN
Assessment of the earthquake induced response of vibratory secondary structures in plane frames
This diploma-thesis deals with the numerical calculation of the seismic response of elastic vibratory secondary structures. Secondary structures are parts of the building, which do not belong to the load-bearing structure. Seismic excitation may lead to large vibration responses when natural frequencies of the load-bearing and the secondary structure are tuned. The main structure is modeled by a generic frame structure with nonlinear material behavior. The first part of this thesis deals with the fundamentals of this study and the derivation of the equations of motions. In addition to the linear elastic - ideal plastic material model the method of static condensation and modal analysis are explained. In the second part the solution algorithm is described. The incremental-iterative formulation of the equations of motions is explained. Furthermore, two di erent iteration procedures for the determination of vibration response of constant ductility are presented. The third section deals with the numerical analysis and interpretation of results. The results of single-degree-of-freedom oscillators and two-degree-of-freedom oscillators are graphically displayed and explained. Finally, the calculations on the frame structures are described and improvements of the approximated solution are demonstrated.