# TSC Torsional Strength

Torsional strength is calculated automatically

**Notation**

* A_{o }=* area of shear reinforcement

*Area of transverse torsion reinforcement*

**A**_{ot }=*Area of transverse shear reinforcement*

**A**_{ov }=*minimum area of longitudinal reinforcement to resist torsion*

**A**_{s-mint }=*web width or diameter of circular section*

**b**_{w }=*distance from extreme compression fiber to centroid of longitudinal tension reinforcement*

**d =***specified compressive strength of concrete*

**f**_{ck }=*design compressive strength of concrete*

**f**_{cd }=*specified yield strength for nonprestressed reinforcement*

**f**_{yk }=*design yield strength for nonprestressed reinforcement*

**f**_{yd }=*specified yield strength of transverse reinforcement*

**f**_{ywk }_{ }=*design yield strength of transverse reinforcement*

**f**_{ywd }_{ }=*critical torsional moment,*

**T**_{cri }_{ }=*design torsional moment,*

**T**_{d }_{ }=Torsional design is made with the reinforcement requirement determined by comparing the factored torsional moment * T_{d}* value with the critical torsion limit

*value.*

**T**_{cr}Torsional effects can be neglected if the design torsional moment at section

is critical torsion limit**T**_{d}**T**_{cr}If design shear force and torsional moment are satisfied the

**TS 500 Eq. 8.10**equation, there is no need to compute torsional stirrups.

**Critical Torsion Limit**

Critical torsion * T_{cri}* is calculated in accordance with

**TS 500 Eq. 8.12.**

* S *is calculated in accordance with

**TS 500 Table 8.2.**

for rectengular section

for T-beam section. **x** and **y** long and short rectengular dimensions of T-beam section.

for circular section.

Minimum shear reinforcement should be satisfied given below;

If design shear force and torsional moment are satisfied the **TS 500 Eq. 8.10** equation, there is no need to compute torsional stirrups.

where * T_{cr}* is computed as follows:

The required minimum closed stirrup area per unit spacing, * A_{o}/s*, is calculated as:

In equiation.

If * T_{d} > T_{cr}* the required longitudinal rebar area, (required minimum longitudinal rebar area),

*, is calculated as:*

**A**_{s-mint}

If * T_{d} > T_{cr}* the required closed stirrup area per unit spacing, is calculated in accordance with

**TS500 Eq. 8.13**as:

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