PRESTRESSED CONCRETE GIRDER PRODUCTION PROCEDURE скачать в хорошем качестве

PRESTRESSED CONCRETE GIRDER PRODUCTION PROCEDURE

Precast prestressed girders are a type of concrete girder that facilitates the rapid construction of a bridge using girders fabricated off-site and then transported and erected into place at the job site. Because these girders require little to no falsework, they are a preferred solution for jobs where construction speed or minimal traffic disruption is required. Prestressed girders are particularly economical when longer beam lengths are required; some types are suitable for spans of up to 200 feet. Prestressing the concrete reduces the size of the required cross-section and the depth of the beam. The smaller cross-section size reduces the self-weight of the beam by requiring less concrete. Prestressing members allows for a lower span-to-depth ratio, which allows for longer spans. The presence of mild steel and high-stress tensioning tendons, when properly designed, minimizes cracking and increases the member’s durability.