Preventing Infrastructure Failures: Lessons from Recent Engineering Disasters

Infrastructure failures can have devastating consequences, leading to loss of life, economic setbacks, and environmental damage. According to the American Society of Civil Engineers (ASCE), the U.S. infrastructure received a C- grade in 2021, with 7.5% of bridges classified as structurally deficient, over 2,300 high-hazard dams, and an estimated repair backlog of $125 billion for bridges alone. Since 2020, at least 50 major infrastructure failures, including bridge collapses, dam failures, and roadway cave-ins, have occurred across the U.S.

Understanding the causes of these failures and learning from past disasters is crucial for engineers and policymakers to prevent future occurrences. This article explores the lessons learned from recent engineering disasters and provides insights into preventing infrastructure failures, with a focus on the concept of von Mises stress.

Understanding Infrastructure Failures

Infrastructure failures occur when structures such as bridges, buildings, dams, and roads fail to perform their intended functions. These failures can result from various factors, including design flaws, material defects, construction errors, and extreme environmental conditions.

Recent Major Engineering Disasters

The Genoa Bridge Collapse (2018): The collapse of the Morandi Bridge in Genoa, Italy (2018), resulted in the deaths of 43 people. Investigations attributed the failure to long-term corrosion of prestressed concrete cables and inadequate maintenance
The Champlain Towers South Collapse (2021): The partial collapse of this residential building in Surfside, Florida, led to 98 fatalities. Structural deficiencies and delayed repairs were identified as primary causes.
The Oroville Dam Spillway Failure (2017): The spillway of the Oroville Dam in California failed, causing the evacuation of nearly 200,000 residents. Poor design and lack of maintenance were key contributors.

Lessons Learned from Engineering Disasters

Importance of Regular Maintenance: Regular inspections and maintenance are essential to identify and address potential issues before they lead to catastrophic failures. The Genoa Bridge collapse highlighted the consequences of neglecting maintenance.
Robust Design Standards: Adhering to stringent design standards and codes can prevent structural deficiencies. The Champlain Towers South collapse underscored the need for rigorous design and construction practices.
Effective Communication: Clear communication between engineers, contractors, and stakeholders is crucial for ensuring that potential risks are addressed promptly. The Space Shuttle Challenger disaster emphasized the importance of communication in preventing failures.
Use of Advanced Simulation Tools: Advanced structural design and analysis software like SDC Verifier enables engineers to conduct Finite Element Analysis (FEA) to assess structural vulnerabilities. Von Mises stress, a key factor in evaluating material failure in ductile structures, helps engineers predict yielding under complex loading conditions.
Apply von Misses Stress: Von Mises stress analysis helps engineers determine whether ductile materials in structures will yield under combined loading conditions. However, engineers must also consider fatigue, buckling, and fracture mechanics for a comprehensive structural assessment.

What is the Role of von Mises Stress in Preventing Failures?

Von Mises stress is a critical concept in engineering design, used to evaluate the strength and durability of materials under complex loading conditions. It helps predict yielding and potential failure points in ductile materials. By understanding von Mises stress, engineers can design safer and more reliable structures.

Von Mises stress theory, also known as the Maximum Distortion Energy Theory, is based on the idea that material deformations occur under the action of multiple forces. It accounts for the entire stress state of a component, making it a powerful tool for predicting the performance of ductile materials.

The von Mises yield criterion is defined as:

Here, K is the yield stress of the material in pure shear.

Application of von Mises Stress in SDC Verifier

SDC Verifier utilizes stress data from FEA software like Ansys, Femap, and Simcenter 3D to calculate von Mises stress based on the general state of stress:

The software employs equivalent stresses, principal stresses, and nominal stresses to perform structural checks. It integrates nominal stress results from FEA programs into its calculations to evaluate failure modes and ensure structural stability.

SDC Verifier applies von Mises stress analysis in compliance with major engineering standards such as DIN 15018 (crane safety), DNV (offshore structures), and Eurocode 3 (steel structures). These standards help ensure material integrity in high-stress applications.