Inelastic Behavior of Steel Buildings in Seismic Zones

Muhammad Tayyab Naqash

doi:10.11648/j.aas.20180301.11

Abstract

This paper provides general overview on the design principles of steel structures in Seismic Zones. In particular, seismic design of multi-storey steel structures using limit states (ultimate, serviceability and damageability) and performance based design approach is firstly discussed and the importance of steel structures is consequently highlighted; then, general concepts to be incorporated in the structural design are provided. The well-known adopted lateral load resisting systems (moment resisting and braced frames) are also criticized to highlight the pros and cons of each system. The concept of dissipative and non-dissipative Zones is given for each lateral load resisting system; and therefore aims to give useful information for the engineers and technicians involved in the design of steel structures in the seismic zones.

Highlights

Structures are designed to sustain safely the applied actions that occur during the life of the building and in service with the aim to have adequate durability and sustainability
The paper has dealt with the examination of the common lateral load resisting systems employed in the design of steel structures
Three conventional seismic load resisting systems were discussed, which are: steel moment resisting frames, eccentric braced frames and cross-concentric braced frames, of which braced frames are much rigid compared to the moment resisting frames and are mostly used in steel structures

Summary

Introduction

Structures are designed to sustain safely the applied actions that occur during the life of the building and in service with the aim to have adequate durability and sustainability. Elastic spectrum is provided by Codes [7,8,9]; whereas, the design spectrum is obtained by reducing it with a specified value (as shown in Figure 1 by their values equal to 1, 2, 3, 4, 5 and 6.5) that depends on the lateral load resisting system known as response modification factor or behaviour factor. Such factor is used to account for the inelastic behaviour of the structural system.

Lateral Load Resisting Systems in Steel

Unbraced Frames

Braced Frames

Conclusions