Prestressed concrete box girder to SIA 262
Prestressed concrete box girder, step by step: predimensioning, tendon layout, losses and serviceability, external prestress, shear and torsion of the webs.
Modules
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Predimensioning
Continuous box girder of constant depth: cross-sections and their properties, actions with load model 1, design moments with the tandems moved along, preliminary prestress.
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Prestress layout
Tendons of a continuous box girder: ducts in the webs with cover and spacing, centroid of the groups, profile along the spans with the minimum radius, couplers and end anchors.
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Prestress losses and serviceability
Tendon force from stressing to time infinity with every loss, equivalent loads, isostatic and hyperstatic moments, stresses at stressing and in service, crack control and deflections.
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External prestress
Unbonded tendons inside the cell: polygon and deviators, friction and losses, deviation forces and hyperstatic moments, bending resistance, stresses and deflections.
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Web shear
Shear envelope and torsion from eccentric traffic, the share carried by the tendons, webs with ducts, compression field and stirrups, transverse bending of the webs.