Design of Alternative Techniques to Mitigate Progressive Collapse in Buildings: Risk-Based Optimization targeting Safety, Economy and Reduction of Greenhouse Gas Emission

• Grant number: 24/23665-2
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: September 01, 2025
• End date: March 31, 2028
• Field of knowledge: Engineering - Civil Engineering - Structural Engineering
• Principal Investigator: André Teófilo Beck
• Grantee: Luiz Eduardo Gonçalves de Mattos
• Host Institution: Escola de Engenharia de São Carlos (EESC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

A significant challenge in structural engineering is the rational design of systems exposed to exceptional events, often referred to as low-probability, high-consequence actions, such as fires, earthquakes, explosions, and impacts. Climate change exacerbates these risks by increasing the frequency and severity of hazards, exposing potential vulnerabilities. Structural robustness refers to the capacity of a structure to withstand such actions, preventing localized initial damage from escalating into disproportionately severe consequences, as the progressive collapse of the whole building. Traditional reinforcement techniques, while mitigating risks, are often costly and may be inefficient under uncertain triggering events or simultaneous failure of multiple elements. Moreover, structural reinforcements typically involve unsustainable material consumption, significantly contributing to greenhouse gas emissions, highlighting the urgent need for sustainable alternatives. Studies reveal a notable lack of multifaceted protection techniques capable of mitigating progressive collapse under different hazards. The main objective of this research project is to proposed alternative protection techniques to mitigate progressive collapse in reinforced concrete systems, targeting structural safety through robustness, while prioritizing cost-efficiency and environmental sustainability. The techniques to be explored include ultra-high-performance fiber-reinforced concretes (UHPFRC), energy absorption devices, traditional reinforcement approaches, and the combination of these to achieve optimized solutions. Effectiveness of these techniques will be evaluated by a risk-based optimization methodology accounting for random and epistemic uncertainties in design variables and hazard probabilities, and aiming to minimize global collapse probability and the associated risks in terms of costs and CO2 emissions. The study focuses on flat slab parking garages exposed to fire and vehicular collisions, as these structures are particularly vulnerable to column loss and to punching shear phenomenon. The expected results include innovative and robust solutions capable of transforming engineering practices, advancing structural safety, sustainability, and cost-efficiency in the construction sector. (AU)