The SAP2000 formulation for shell reinforcement design is based on the following publications:

• Brondum-Nielsen, T. (1974). Optimum Design of Reinforced Concrete Shells and Slabs , Report NR.R 44, Technical University of Denmark, Copenhagen, Denmark.

• Marti, P. (1990). Design of Concrete Slabs for Transverse Shear , ACI Structural Journal, 87(2), 180-190.

The formulation is documented in the technical note Concrete Shell Reinforcement Design, available through Help > Documentation > Technical Notes > Concrete Shell Reinforcement Design.

Setting shell design parameters

Default shell design parameters, such as rebar cover, may be modified through Define > Section Properties > Area Sections, as shown in Figure 1:

Figure 1 - Set default shell design parameters

Reviewing results

After analysis is run, design parameters may be reviewed through Display > Show Forces/Stresses > Shells by selecting the component type Concrete Design, as shown in Figure 2:

Figure 2 - Review design parameters

ASt1 represents reinforcement in the 1 direction of the shell, and ASt2 is in the 2 direction. The reinforcement calculated for either the top or bottom face of the shell object may be displayed separately, as shown in Figure 3:

Figure 3 - Reinforcement for top or bottom surface and orientation