For AASHTO LFD, design of shear is carried out according to AASHTO specifications. However, if torsion is present in the section along with shear, torsion design is based on ACI 318-95 specifications (as suggested by AASHTO Standard specifications).

In AASHTO Standard, when the torsion is less than the limiting torsion, the maximum spacing is based on Art. 8.19.3. However, when torsion is more than the limiting value, program also checks the spacing as per ACI 11.6. Beam properties for torsion (Aoh and ph) consider the stirrup size, specified or chosen for Auto Design. For the calculation of Aoh, the program uses the rebar clear cover for sides to be equal to the value specified on A/D parameters dialog for cap side cover. Computed Avs/s is the required steel for shear only, 2Ats/s is the required steel for two legs of torsion, and Av/s is the total computed steel due to shear and torsion at that section. When torsion is present at a section, the program also calculates longitudinal steel. For AASHTO Standard, the program reports the total longitudinal steel required for torsion (Alt). Users may reduce this amount by provided steel in excess of required steel already present at that section.