Section 3.4.5.13 Torsion

Included code sections - 2.4.1, 2.4.2, 2.4.4 (part) to 2.4.8

Excluded code sections - 2.4.3, 2.4.4 (part), 2.4.9, 2.4.10

Note: All code references in this section refer to BS 8110, Part 2

Only the "core" of a cross section is used for torsion design. See Concrete Core Determination .

Torsional shear stress v_t is calculated using section 2.4.4.1 equation 2.

Maximum combined shear stress v_tu is calculated by Table 2.3, note 2 including the y₁ modification factor and compared to v_t. Any remaining capacity is used to calculate maximum remaining shear capacity.

Shear and torsion reinforcement is provided in accordance with Table 2.4.

Area of torsion links and longitudinal reinforcement is calculated in accordance with section 2.4.7.

Maximum spacing of links is the least of x₁, y₁ /2 or 200 mm.

If torsion design is selected, at least minimum links will be provided at all locations.

Note: Assume γ in equations in table 2.3, note 2 is a misprint, and should instead be

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