When a person gets frustrated or stressed out, they will often dwell on their problems, which only serves to increase their stress levels. A similar phenomenon occurs in metal – and, appropriately enough, it's called fatigue.Fatigue occurs when the heavy load on a metal fluctuates and causes it to lose strength. People first noticed this phenomenon during the industrial revolution, when machinery would sometimes break when it was moved.

Fatigue in Structures

The study of structures began in the seventeenth century, thanks largely to Galileo. Galileo had to switch disciplines after the Catholic Church threatened to persecute him for his work in the field of astronomy in 1633. He left astronomy behind and began studying the strength and character of different physical materials.

Structures are a fundamental part of both the man-made and natural worlds. And while a rooftop and a horse would seem to have little in common, they're affected by the same scientific concepts that keep structures intact. Stress, strain, force and strength are the keys to designing and maintaining the structures so important to our everyday lives, and researchers play a critical role in keeping us safe from their collapse.

Structures and Our Life

Galileo’s prestige brought greater academic attention to the subject. In the mid-1650s, scholars began researching the ways in which different materials and structures behave under heavy loads. That same century, Robert Hooke also discovered how matter behaves at an atomic level.

What are structures?What holds an airplane together as it moves through the air or keeps a bridge from collapsing under the strain of cars? It’s all in the design of their structure.A structure is a collection of materials intended to sustain loads.

Structures: Or Why Things Don't Fall Down

Stress isn’t just a psychological problem affecting humans – structures can suffer from stress as well.Stress tells us the degree to which atoms are being pushed apart. Strain, on the other hand, measures how far they’re being pushed apart

Stress and strain

Some structures, like ancient churches, castles or monuments, have managed to stay intact for centuries or even millennia. What makes it possible for them to stay standing for so long?Structures stay in place largely thanks to the compressive forces acting upon them. Unlike tensile forces, compressive forces push on a structure rather than pulling it.Ancient people implicitly understood the principles of structures and their forces well before they could perform calculations about them.

Structures built on compression

Structures can fall apart when they develop cracks or when new material is added onto them. C. E. Inglis wrote about this in 1913.Holes and cracks aren't the only agents of local stress, either. The addition of new material can also cause stress by increasing the structure's stiffness. So, if you put a patch on a torn piece of clothing, for example, it might just cause it to tear even more.

Cracks and Structure

Structural engineering is important for societies around the world to ensure that the structures around us are safe and fit for purpose. This is a big responsibility for structural engineers who design structures to withstand the stresses and environmental impacts they are subjected to daily

In a book that Business Insider noted as one of the "14 Books that inspired Elon Musk," J.E. Gordon strips engineering of its confusing technical terms, communicating its founding principles in accessible, witty prose. For anyone who has ever wondered why suspension bridges don't collapse under eight lanes of traffic, how dams hold back-or give way under-thousands of gallons of water, or what principles guide the design of a skyscraper or a kangaroo, this book will ease your anxiety and answer your questions. J. E. Gordon strips engineering of its confusing technical terms, communicating its founding principles in accessible, witty prose.

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