# Beam Reinforcement Limits.

Longitudinal and Transverse reinforcement limits are controlled automatically.

**International Design Codes**

* ACI 318-19 : *Beam Reinforcement Limits

* TSC 2018 : *Longitudinal Reinforcement Limits for Beams Transverse Reinforcement Detailing for Beams.

**Notation in ACI 318-19**

* A_{cp }= *area enclosed by outside perimeter of concrete cross section, in.

^{2}

*total area of longitudinal reinforcement to resist torsion, in.*

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

*minimum area of longitudinal reinforcement to resist torsion, in.*

**A**_{l,min }=^{2}

**A**_{s}**area of nonprestressed longitudinal tension reinforcement, in**

_{ }=^{2}

*minimum area of flexural reinforcement, in.*

**A**_{s},_{min }=^{2}

*area of one leg of a closed stirrup, hoop, or tie resisting torsion within spacing s, in.*

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

*area of shear reinforcement within spacing s, in.*

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

*minimum area of shear reinforcement within spacing s, in.*

**A**_{v},_{min }=^{2}

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

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

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

**f**_{c}^{' }_{ }_{ }=

**√f**_{c}‘*square root of specified compressive strength of concrete, psi*

^{ }_{ }=*specified yield strength for nonprestressed reinforcement, psi*

**f**_{y }=*specified yield strength of transverse reinforcement, psi*

**f**_{yt }_{ }=*overall thickness, height, or depth of member, in.*

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

**s =***cracking torsional moment, in.-lb*

**T**_{cr }_{ }=*threshold torsional moment, in.-lb*

**T**_{th }_{ }=*nominal torsional moment strength, in.-lb*

**T**_{n }_{ }=*factored torsional moment at section, in.-lb*

**T**_{u }_{ }=*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 }=*strength reduction factor*

**ϕ =***= modification factor to reflect the reduced mechanical properties of lightweight concrete relative to normalweight concrete of the same compressive strength*

**λ***= ratio of*

**ρ**_{ }*to*

**A**_{s}

**bd****Next Topic**