ABSTRACT
One of the basic factors contributing to the proper seismic behaviour of a building is a rational conceptual design of the structural system in a way that lateral seismic actions (inertiaforces) are transferred to the ground without excessive rotations of the building and in a ductile manner. This cannot be achieved only through mandatory requirements of the Code. Therefore, there are also some general principles that can lead to the desirable result when they are followed. The guidelines that should govern a conceptual design against seismic hazard according to EC8-1/2004 are
• Structural simplicity • Uniformity and symmetry • Redundancy • Bi-directional resistance and stiffness • Torsional resistance and stiffness • Diaphragmatic action at storey levels • Adequate foundation
It should be mentioned that after a thorough examination of the 103 most badly damaged or collapsed R/C buildings in Athens after the earthquake of Parnitha (7 September 1999), it was found that 29 of these buildings had failed mainly due to their poor configuration (OASP, 2000). This was attributed mainly to the absence of collaboration between the architect and the structural engineer at the early stages of planning when a satisfactory compromise could have been reached. Of course, this is a usual situation only in small-and medium-sized buildings where there are not distinct stages of a preliminary design, predesign, and final design where this collaboration is consolidated.
