# Shear Wall Shear Design.

Wall design shear strengths are calculated automatically.

Wall required shear strengths are calculated automatically.

**International Design Codes**

* ACI 318-19 : *Shear Wall Shear Design

* TSC 2018 : *Design Shear Forces for Walls Wall Design Shear Strength Calculation

**Notation in ACI 318-19**

* A_{cv } = *gross area of concrete section bounded by web thickness and length of section in the direction of shear force considered in the case of walls, and gross area of concrete section in the case of diaphrams. Gross area is total area of defined section minus area of any openings, in.

^{2}

*area of concrete section of an individual pier, horizontal wall segment, or coupling beam resisting shear, in*

**A**_{cw}=^{2}.

*width of compression face of member, in.*

**b**_{w }=*dead load*

**D =***earthquake load*

**E**_{ }=*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 }=

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

**h**_{w}**=**height of entire wall from base to top, or clear height of wall segment or wall pier considered, in.

**h**_{wcs}**=**height of entire structural wall above the critical section for flexural and axial loads, in.

*length of clear span measured face-to-face of supports, in.*

**l**_{n}_{ }=*unsupported length of column or wall, in.*

**l**_{u}_{ }=

**l**_{w }**=**length of entire wall, or length of wall segment or wall pier considered in direction of shear force, in.

*live load*

**L**_{ }=*roof live load*

**L**_{r}_{ }=

**M**_{u}**factored moment at section, in.-lb**

_{ }=

**M**_{pr }**=**probable flexural strength of members, with or without axial load, determined using the properties of the member at joint faces assuming a tensile stress in the longitudinal bars of at leasts 1.25

*f*and a strength reduction factor

_{y}*ϕ*of 1.0, in.-lb

*number of stories above the critical section*

**n**_{s}=

**P**_{n}**nominal axial compressive strength of member, lb**

_{ }=

**P**_{u}**factored axial force; to be taken as positive for compression and negative for tension, lb**

_{ }=*rain load*

**R**_{ }=*snow load*

**S**_{ }=

**N**_{u}**factored axial force normal to cross section occurring simultaneously with**

_{ }=*or*

**V**_{u}*; to be taken as positive for compression and negative for tension, lb*

**T**_{u}positive for compression and negative lb

*design shear force for load combinations including earthquake effects, lb*

**V**_{e }=*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 }=*factored load per unit length of beam or one-way slab, lb/in.*

**w**_{u }=*wind load*

**W**_{ }=*coefficient defining the relative contribution of concrete strength to nominal wall shear strength*

**α**_{c }=*strength reduction factor*

**ϕ =***= overstrength factor equal to the ratio of*

**Ω**_{v}*at the wall critical section*

**M**_{pr}/M_{u}*= modification factor to reflect the reduced mechanical properties of lightweight concrete relative to normalweight concrete of the same compressive strength*

**λ***factor to account for dynamic shear amplification*

**ω**_{v}=*= ratio of area of distributed longitudinal reinforcement to gross concrete area perpendicular to that reinforcement*

**ρ**_{l }*= ratio of area of distributed transverse reinforcement to gross concrete area perpendicular to that reinforcement*

**ρ**_{t }**Next Topic**