Response spectrum analysis of reinforced concrete frames having mass irregularity
- Vol.38(1), Jan-Mar
- Pune NICMAR 2023
- 5-15p.
Purpose: Irregularities either in elevation or plan are chief sources of structural collapse during an earthquake. Hence, in zone of high seismicity, these irregular structures are of concern. Therefore, purpose of present study is to investigate the seismic response of reinforced concrete (RC) frames having vertical mass irregularity.
Study design/methodology/approach: A total of five frames having mass irregularities at floor levels two (IF-1), three (IF-2) and four (IF-3) respectively and one simple reference frame (RF) have been considered. Response spectrum analysis has been performed on these models in STAAD pro. Further, extensive parametric studies have been executed to investigate the effect of seismic zone factor and soil category.
Findings : The results have been debated in terms of peak storey shear, lateral displacement and drift ratio and compared with the Indian standard (IS-1893:2016) allowable limits. It has been found that in zone IV and V (soil category I, II and III), drift ratio was pragmatic to be more than the threshold limit. However, drift ratio is enhanced for IF-3 i.e., when mass was present at higher storey level.
Originality/value: In current literature limited research articles on earthquake response of mass irregular buildings can be found. Also, these articles have not yet addressed the influence of parameters such as zone factor and soil category.
Research limitations/implications: Since seismic effect was found to be dominant in x-direction and henceforth discussions have been focused on the results acquired for x-direction only.