Risk-Based Design of Regular Plane Frames Subject to Damage by Abnormal Events: A Conceptual Study

Author(s)

Beck, Andre T. ^[1] ; Ribeiro, Lucas da Rosa ^[1] ; Valdebenito, Marcos ^[2] ; Jensen, Hector ^[3]

Affiliation

^[1] Univ Sao Paulo, Dept Struct Engn, Av Trabalhador Sao Carlense 400, BR-13566590 Sao Carlos, SP - Brazil

^[2] Univ Adolfo Ibanez, Fac Engn & Sci, Av Padre Hurtado 750, Vina Del Mar 2562340 - Chile

^[3] Univ Tecn Federico Santa Maria, Dept Obras Civiles, Av Espana 1680, 110V, Valparaiso - Chile

• Document type: Journal article
• Source: JOURNAL OF STRUCTURAL ENGINEERING-ASCE; v. 148, n. 1 JAN 1 2022.
• Web of Science Citations: 0

Abstract

Constructed facilities should be robust with respect to the loss of load-bearing elements due to abnormal events. Yet, strengthening structures to withstand such damage has a significant impact on construction costs. Strengthening costs should be justified by the threat and should result in smaller expected costs of progressive collapse. In regular frame structures, beams and columns compete for the strengthening budget. In this paper, we present a risk-based formulation to address the optimal design of regular plane frames under element loss conditions. We address the threat probabilities for which strengthening has better cost-benefit than usual design, for different frame configurations, and study the impacts of strengthening extent and cost. The risk-based optimization reveals optimum points of compromise between competing failure modes: local bending of beams, local crushing of columns, and global pancake collapse, for frames of different aspect ratios. The conceptual study is based on a simple analytical model for progressive collapse, but it provides relevant insight for the design and strengthening of real structures. (AU)

• FAPESP's process: 19/13080-9 - Optimal reliability-based design of structural systems considering progressive collapse
• Grantee: André Teófilo Beck
• Support Opportunities: Regular Research Grants