# Two-Way Slab Design Strength.

Both flexural moment and shear strength is controlled automatically according to *Codes.*

Dimensions of the cross-section should be satisfy *Codes***. **It’s automatically controlled and users are warned if the rule is not satisfied.

**International Design Codes**

* ACI 318-19 : *Two-Way Slab Design Strength per ACI 318-19 with ideCAD

* TSC 2018 : *Punching Shear Stress at Critical Section (7.11.8)

**Symbols in ACI 318-19**

* M_{u }= *factored flexural moment at section, lb

*nominal flexural strength at section, in.*

**M**_{n }=*factored slab moment that is resisted by the column at a joint, in.-lb*

**M**_{sc }=**f'**specified comprehensive strength of concrete, psi

_{c}=*area of concrete used to determine shear stress, in*

**A**_{c-sh }=^{2}

*gross area of concrete section, in*

**A**_{g }=^{2}

*web width or diameter of circular section, in.*

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

**d =***overall thickness, height, or depth of member, in.*

**h =***center-to-center spacing transverse reinforcement, in*

**s =***nominal shear strength provided by concrete, lb*

**V**_{c }=*nominal shear strength, lb*

**V**_{n }=*nominal shear strength provided by shear reinforcement, lb*

**V**_{s }=*factored shear force at section, lb*

**V**_{u }=**γ**

*factor used to determine the fraction of M*

_{f }=_{sc}transferred by slab flexure at slab-column connections

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