Seismic response of low-to-high peak ground acceleration earthquakes in RC framed buildings with scrap tyre as base isolator using fast nonlinear analysis technique

The performance of scrap tyre rubber pads (STRP) fabricated by used automobile tyres as seismic shock absorbers is evaluated in this study. STRPs are extremely good in low-rise buildings, even in places with high seismic risk, and are cost-efficient in developing countries. The SAP 2000 software package was used to study four-storey normal buildings of one type and irregularly shaped buildings such as plan irregularity (H shape, square core type, and plus type) and vertical geometry irregularity (two types) of fixed and STRP base. The study is carried out using the Fast Nonlinear Analysis (Nonlinear Modal Time History Analysis) approach. This procedure yields real and accurate outcomes in a shorter amount of time. The STRPs, for example, are developed utilizing UBC-97 design principles that are relevant for Indian circumstances. The six different real-time-history records selected based on peak ground accelerations are examined for convergence using SeismoMatch software. Most importantly, IS code matching is accomplished for all soil conditions. The dynamic parameters of the buildings were determined and discussed, including base shear, acceleration, storey displacement, storey drift, storey drift ratio, and hysteresis loops with respect to magnitude and Peak ground acceleration (PGA). The analysis demonstrates that the base shear reduction is prominent in EQ1 (PGA-0.876 g) and EQ5 (0.534 g) for plan irregularity type buildings compared to regular type and vertical irregularity type buildings. Furthermore, maximum acceleration reduction is achieved in regular type buildings compared to other buildings with STRP base of about 30–40% during EQ1 (PGA-0.876 g) and EQ5 (0.534 g). Subsequently, storey displacement and drift responses are significant in vertical geometry irregular buildings compared to plan irregular type and regular one. Therefore, it is translucent from the investigation is that the seismic responses of the buildings are predominantly influenced by the structural elements and the intensity/PGA of the seismic events irrespective of its irregularity profile. © 2022, The Author(s), under exclusive licence to Springer Nature Switzerland AG.