Author(s)

S. Zdravkovic, D. Zlatkov, B. Mladenovic & M. Mijalkovic

Abstract

In this paper forming of the stiffness and mass matrices for a bar with semi-rigid connections depending on the level of rigidity of the joint connection will be presented. These two matrices are introduced into well-known computer programs to be modified for the dynamic design of a plane linear system whose connections are semi-rigid. The influence of semi-rigid connections on the change of dynamic characteristics is illustrated using numerical examples. Horizontal seismic forces and maximal horizontal displacements of a frame are computed according to Serbian regulations, based on the circle frequencies and vibration periods of free horizontal frame vibrations calculated for different levels of connection rigidity. The results obtained are presented in diagrams. This paper will also briefly present the results of an integral experimental investigation of seismic performances of the prefabricated reinforced concrete structural system AMONT, developed in Serbia and intended for construction of various types of modern industrial halls. The study has been carried out for the purpose of attesting the structural behaviour in seismic regions, particularly its specific connections and links. It is concluded from the results obtained that the rigidity level of connections should not be neglected, particularly in the analysis of prefabricated structures. The design allowing for semi-rigid connections is especially significant in earthquake engineering, because seismic forces cause the joint connections to become slack, which has not been adequately taken into consideration in up-to-date dynamic analysis. Keywords: semi-rigid connections, stiffness matrix, consistent mass matrix, circle frequency, vibration period, pre-cast reinforced concrete structural system, seismic design.

Keywords

semi-rigid connections, stiffness matrix, consistent mass matrix, circle frequency, vibration period, pre-cast reinforced concrete structural system, seismic design.