Introduction

The history of bridge engineering is written not only in the successes that span rivers and connect communities, but also in the failures that have taught us invaluable lessons about design, construction, and maintenance. Each major bridge failure represents a tragedy for those directly affected, but these disasters have also served as crucial learning experiences that have made modern bridges safer and more reliable. The engineering profession has a unique characteristic: it learns from its failures as much as from its successes, and this learning process has been essential to the development of safe bridge design practices.

Bridge failures, while relatively rare considering the thousands of bridges built throughout history, have had profound impacts on engineering practice. Each failure has revealed weaknesses in design philosophy, analysis methods, material understanding, or construction practices that were previously unrecognized. The investigation of these failures and the implementation of improved practices based on lessons learned has been a driving force in the evolution of bridge engineering.

This chapter examines four of the most significant bridge failures in history: the Tacoma Narrows Bridge collapse of 1940, the Quebec Bridge disasters of 1907 and 1916, the Silver Bridge collapse of 1967, and the I-35W bridge collapse of 2007. Each of these failures occurred for different reasons and taught the engineering community different lessons. By understanding what went wrong and how the profession responded, we can appreciate both the complexity of bridge engineering and the continuous process of improvement that keeps our modern infrastructure safe.

The study of bridge failures serves multiple purposes: it honors those who lost their lives in these tragedies, it provides critical learning experiences for current and future engineers, and it demonstrates the importance of rigorous design, careful construction, and ongoing maintenance in ensuring bridge safety. Most importantly, it shows how the engineering profession has evolved to prevent similar failures from occurring again.