Reinforced concrete torsion design to Eurocode 2.

Enter the section and torsion (with any coexistent shear), and Volex Anvil designs for torsion by the EC2 §6.3 thin-walled tube analogy: the maximum torsional resistance TRd,max, the check on combined torsion-and-shear, and the additional longitudinal steel Asl and closed links required.

The design follows EC2 §6.3.2 and Mosley, Bungey & Hulse §8.5, with the equivalent thin wall, TRd,max and reinforcement all shown for checking.