Comparison of Damage Indexes in Performance Assessment of Special Concrete Moment Resisting Frames

Abstract

The earthquake is one of the natural disasters that caused the many death. 10,000 people die annually due to earthquake around the world, and this incident has so far caused a lot of economic damages. In the structures review, earthquake damages can be classified into three categories: physical, social, and economical. In order to quantify physical damages, it is possible to introduce damage indexes. By knowing the damages of a structure, in addition to determining a proper understanding, redlines are possible to be designed. In other words, knowing the damage index in a structure makes it possible to determine the structure stablity against forces such as earthquakes. This issue becomes more important in retrofitting programmes. In this research, which the purpose is to determine the earthquake damages and structure performance, the Drift and Ghobarah Index are selected as damage Indexes, and the effects on the performance of two-dimensional special concrete moment resisting frames designed with the regulation (ACI 318-14) and the American loading standard (ASCE 7-10) has been investigated. In this regard, performance levels with the Drift index and the Ghobarah index along with the estimated damages have been investigated in different analysis and the correlation between these two Indexes is established. Analyses results show that Ghobara index is more conservative than maximum drift index. Another obtained result is that intensity measure which cause to low rise and medium rise buildings to reach life safety level has about 50% and 40 % differences, respectively, for two assumed indices.

Keywords

• damage indicators
• drift damage index
• ghobarah damage index
• performance levels
• incremental dynamic analysis