Bridges presentation
stresses under a moving load created a lack of aerostatic stability and eventual failure. It took
engineers another quarter-century to perfect bridge design according to advanced theories of stress
analysis, understanding of material properties, and renewed respect for the forces of nature. A
definitive understanding of the physical oscillations and vibrations of structures did not occur until
the middle of the 20th century after the Tacoma Bridge collapse in the USA in1940.
Advances in design theory, graphic statics, and a knowledge of the strength of materials by
engineers such as Karl Culmann and Squire Whipple were achieved in the second half of the 19th
century, but the factor that most influenced the scientific design of bridges was the railroads.
Engineers had to know the precise amount of stresses in bridge members to accommodate the
thundering impact of locomotives. Founded on the pioneering work of the American Squire Whipple
annaabi.ee 
