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@article{193095,
        author = {Samajhana Shahi and Prof.Dr Rekha Shrestha and Keshab Shahi},
        title = {Seismic Performance of Urban Buildings with Absence Seismic Gaps:A Study on the Effects of Concrete Grades and Column Sizes},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {12},
        number = {11},
        pages = {4027-4032},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=193095},
        abstract = {In today's world, buildings are often found to be constructed with absence seismic gaps because of unplanned urbanization, limited availability of land, and peoples demand. Urban buildings in close proximity are often constructed without adequate seismic separation gaps, resulting in the potential for damaging interactions during earthquakes. This study investigates the seismic performance of urban buildings with absence seismic gaps, focusing specifically on the influence of varying concrete grades and column sizes. Ten structural configurations were modeled, ranging from single buildings of uniform material to adjoining buildings with differing concrete strengths (M20, M25), varied column dimensions (350 × 350 mm, 400 × 400 mm), and height differences. Time history analysis was conducted using the 2015 Gorkha Earthquake ground motion to evaluate storey displacement, inter-storey drift, base shear, and overturning moment for each configuration. Results indicate that adjoining buildings with different concrete grades but identical heights exhibit the highest seismic demands, while single buildings with uniform higher-grade concrete perform best across all measured parameters. The findings highlight the significant influence of material inconsistency and column sizing on seismic response when separation gaps are absence. The study concludes with design recommendations for minimizing seismic vulnerability in dense urban environments and suggests directions for future research on structural interaction mitigation.},
        keywords = {Absence seismic gaps, Inter-story drift, Time History Analysis, Seismic Performances.},
        month = {April},
        }