Structures: Or why things don’t fall down.A very interesting book, covering a wide field of topics, from the ground up you might say.
Basic concepts of forces are addressed. Compression, tension, shear and torsion forces, and their occurrence in everything from bridges, ancient coliseums, trees, boats and human biology. This, the author does very well; constantly interweaving the effects of various types of strains and stresses and fractures as they occur in wood construction and metal beams, as well as human skeletons and arteries.
Reasons for, and types of failure are described for wood, concrete, boat sails, steel, femurs and aortas. Advantageous shapes of design for handling wind and accepting impacts are given, and reasons for spoke wheels. Critical and safe limits of fatigue and fracture are described…historical cases are offered, describing why early aero planes crashed and bridges fell down, and why boats capsize.
Cautions are pointed out. Over design of repair: The repair must work in harmony with the repaired material, and not be so unyielding that it works against it. So many invisible forces of tension and compression are at play, and violation of acceptable limits must be watched for when they manifest in fractures.
Different approaches to bridge trusses are explained, not so much mathematically, but in concepts of load bearing and the transference of force throughout the truss. By way of example, Bowstring bridges seem quite clever in design, where the internal force of the arch pulls the roadway below it taught so that the whole thing is held in equilibrium like a bow and arrow on a giant scale.
The all important “thrust line” is a constant theme from chapter to chapter. Now I know why those old cathedrals have so many spires and spooky statues way up there, and it’s not for warding off evil spirits, it’s because they’re heavy.
There are photographs, all clumped together in the middle of the book. Black and white, kind of blurry, but still a helpful aid. Very nice drawings, not blurry, and graphs are abundant in all chapters to help visualize the topics being discussed.
These and many more topics and application fill this book, none of it came across as boring or dry.
Beyond the final chapter, a few concepts are given a light mathematical treatment. Moments in I-beams, deflections in cantilevers and so forth.
The pages are made of sturdy heavy paper, the printing is nice size and clear for those who require reading glasses, with ample space around the print for making marginal notes.
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