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Why can prestressed concrete be used to build long bridges and wide roofs?

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Cement The cement-making process, from crushing and grinding of raw materials, through roasting of the ground and mixed ingredients, to final cooling and storing of the finished product.

Prestressed concrete is uniquely suited for long bridges and wide roofs because it allows structural members to carry significantly greater loads and span longer distances than ordinary reinforced concrete.21

The process works by placing the concrete into a state of compression using high-tensile steel wires or cables, either through pretensioning or posttensioning. This internal compression acts like a spring, creating a live force that counteracts the tensile bending stresses caused by applied loads. By neutralizing these stretching forces, the material prevents the ruptures that would typically occur in ordinary concrete.213

Because prestressed concrete effectively manages these stresses, it allows engineers to design structures that are lighter, shallower, and more elegant. This reduction in depth and material weight is particularly advantageous for large-scale projects, such as the cantilever construction of long-span bridges, where it enables the creation of structures that compete directly with steel in both performance and aesthetic profile.14