References
ACI 318-14
PCI Design Handbook 8th Edition
Mast, Robert F. “Analysis of Cracked Prestressed Concrete Sections: A Practical Approach.”
Serviceability Class
The service class is determined by using the stress limits defined in ACI 318-14 table 24.5.2.1 (classification of prestressed flexure members based on ft). The stress multipliers defined in this section are the default values in Eriksson Beam but may be overridden by the user. Once the service class is determined table 24.5.2.1 (service design requirements) is used to determine which checks are required.
Deflection Methodology
To calculate deflections, Eriksson Beam uses the effective moment of inertia method for mildly reinforced members and bilinear deflections for prestressed members. Note that if the prestressed member remains uncracked the bilinear deflections will only use gross, uncracked, section properties. More information on the deflection calculation procedure can be found below in the More Information section.
Cracked Section Properties
Cracked section properties for both prestressed and mildly reinforced member are computed using the procedure given by Robert Mast in his paper “Analysis of Cracked Prestressed Concrete Sections: A Practical Approach.” This procedure is summarized in the PCI Design Handbook section 5.2.2.2, but for more detailed explanation see the paper above. For Class C prestressed components, Δfps is calculated as part of this procedure as well.