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@article{207500,
        author = {Shamal Raut and GIRISH JOSHI},
        title = {Progressive Collapse Assessment of a G+30 Reinforced Concrete Tall Building Using the Alternate Path Method},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {13},
        number = {3},
        pages = {1225-1230},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=207500},
        abstract = {Progressive collapse is a disproportionate failure mechanism in which the local loss of a load-bearing member produces force redistribution demands that may exceed the reserve capacity of adjoining elements. This paper presents a journal-oriented analytical investigation of a G+30 reinforced concrete tall building subjected to a sudden column-removal scenario using the Alternate Path Method. A three-dimensional ETABS model was developed with M30 concrete, Fe500 reinforcement, 150 mm slab thickness, 250 mm x 450 mm beams and 500 x 500 mm/400 x 400 mm columns. Gravity, wind and seismic actions were considered using relevant Indian code provisions, while structural robustness was evaluated through storey shear, lateral displacement, storey drift and demand-capacity ratio indicators. The removal of the critical column produced a uniform 56% increase in storey shear demand, increased top displacement from 92.0 mm to 143.5 mm and raised the maximum drift from 5.50 mm to 8.58 mm. Despite this increase, the serviceability displacement demand remained below the H/500 limit and the drift demand remained below the IS 1893 limit of 0.004h. The maximum shear DCR increased from 0.62 to 0.97, indicating near-critical reserve capacity at the base. The study demonstrates that alternate load-path evaluation can identify vulnerable zones before disproportionate collapse occurs and can support robustness enhancement through member strengthening, redundancy and improved continuity detailing.},
        keywords = {Progressive collapse; Alternate Path Method; Demand capacity ratio; Tall building; ETABS; Column removal; Structural robustness},
        month = {August},
        }