Indirect Analysis Method in Design for Stability of Structural Steel Buildings

Abstract

There are three methods of design for stability defined in AISC 360-16 Specification for Structural Steel Buildings, namely Direct Analysis Method (DAM), Effective-Length Method (ELM), and First-Order Analysis Method (FOM). DAM is the method that is featured by AISC. Based on DAM, Rafael Sabelli proposed another method called Indirect Analysis Method (IAM). IAM is a new method that has not generally been used, and also has not been included in the AISC Specification. This research is conducted in order to study IAM and compares the analysis results of IAM with those of DAM. Using a nonlinear structural analysis software, design and analysis were conducted for stability design of an eight-story building loaded with dead load, live load, and wind load. IAM provides a simple amplifier approach which is called B3 to address the member inelasticity, member imperfections, and uncertainty in member stiffness. From the study that has been conducted, the analysis results using IAM show close values with those of DAM, in terms of demand-to-capacity ratios, with IAM is more conservative than DAM. The use of IAM simplifies the design process without affecting the economy of the design.

Keywords

• metode analisis langsung, metode panjang efektif, metode analisis orde pertama, metode analisis tidak langsung, desain terhadap stabilitas