Progressive Collapse Analysis — Design & Simulation

Abstract — Progressive Collapse Analysis

Progressive Collapse Analysis: Civil & Structural Engineering Comprehensive Investigation Integrated Analysis: ETABS · STAAD.Pro · GIS/QGIS · ABAQUS FEA · MATLAB · IoT Sensors · ~3737 Words Chapter 1: Structural Engineering Modeling & Problem Statement Progressive collapse is a structural failure phenomenon in which the local failure of a primary load-carrying element triggers a chain reaction that may lead to partial or total collapse of a structure. This study evaluates the progressive collapse behaviour of three reinforced cement concrete (RCC) framed building configurations: T-shaped, I-shaped, and Core-rectangular structures. All buildings are modelled as G+10 storey structures with identical parameters and analysed using ETABS and STAAD.Pro based on GSA (2016) guidelines. The structures are designed considering gravity and lateral loads according to IS 875 (Part 1, Part 2, Part 3) and IS 1893 (Part 1):2016. Progressive collapse is simulated by removing all columns individually, one at a time, to study the response of the remaining structural system. The structural performance is evaluated using Demand Capacity Ratio (DCR), joint displacement, and Damage percentage under variation b/w ETABS Ultimate 18.0.2 & STAAD.Pro V8i evaluated by using bending moment, shear force under wind and earthquake load combinations from both software's. Columns producing one or more member failures are identified as Critical Columns, while those causing the maximum number of failures are identified as Governing Columns. Reinforcement detailing of beams, columns, and slabs is also examined, where ETABS models are detailed using CSI Detail v18.1.1 and STAAD.Pro V8i provides direct reinforcement results for beams and columns, with slab behaviour evaluated through stress distribution. The results show that the T-shaped structure has better progressive collapse resistance, with fewer failed members and lower damage compared to the I-shaped and Core-rectangular structures. The damage is reduced by about 48% compared to the I-shaped structure and 28% compared to the Core-rectangular structure. The I-shaped structure shows the highest number of beam failures, while the Core-rectangular structure experiences higher column demand due to load concentration near the core. The results from ETABS and STAAD.Pro show similar behaviour, with a variation of about 8–14% under wind and earthquake load combinations. The results indicate that structures which efficiently redistribute loads to surrounding members after column removal exhibit better resistance to progressive collapse.

Analytical & Numerical Modeling Methodology

Section 1.1: Structural Analysis and Finite Element Modeling Formulation for Progressive Collapse Analysis. The structural analysis of Progressive Collapse Analysis incorporates linear and non-linear numerical formulations to predict deformed shapes, shear force distributions, bending moment envelopes, and axial load interactions. Computational software platforms including ETABS and STAAD.Pro utilize spatial 3D stiffness matrices governed by the equilibrium equation [K]{u} = {F}, where [K] represents the assembled global structural stiffness matrix, {u} is the nodal displacement vector, and {F} denotes external load vectors. P-Delta geometric non-linearity is incorporated to account for second-order sway effects induced by elevated gravity loads and lateral wind or seismic forces. Dynamic modal analysis employs Ritz and Eigenvector algorithms to extract natural frequencies, mode shapes, and modal mass participation ratios exceeding 90% in principal directions. Design verifications conform strictly to international standards including IS 456, IS 1893 (Part 1) for earthquake resistance, ACI 318, and Eurocode 2/8 guidelines.

Finite Element Results & Code Compliance

Section 2.1: Geotechnical Engineering, Foundation Mechanics & ABAQUS Non-Linear Simulation for Progressive Collapse Analysis. Geotechnical considerations for Progressive Collapse Analysis require characterizing soil-structure interaction (SSI), subsurface stratigraphy, and foundation settlement limits. Non-linear continuum mechanics models executed in ABAQUS employ Mohr-Coulomb plasticity, Cam-Clay, and Concrete Damaged Plasticity (CDP) constitutive models. Soil layers are discretized using 8-node brick continuum elements with reduced integration (C3D8R) to mitigate shear locking under high confining pressures. Interface contact formulations apply master-slave penalty algorithms with frictional shear traction limits defined by Coulomb's law: tau = c + sigma*tan(phi). Pore-water pressure dissipation, consolidation settlement, and liquefaction vulnerability indices are numerically evaluated to prevent differential settlement under transient dynamic vibrations.

Scope & Practical Applications

• High-rise building and spatial frame analysis under seismic & wind loading
• Finite element continuum modeling in ABAQUS for non-linear material plasticity
• Classical lamination theory (CLT) and failure prediction for composite structures
• Spatial hazard mapping, landslide susceptibility, and catchment terrain analysis in QGIS
• Detailed bar bending schedules (BBS), structural drawings, and calculation booklets