# Shear Wall Required and Design Strength

Wall required strengths are calculated automatically.

Wall design strengths are calculated automatically.

**Notation**

* A_{g }= *gross area of concrete section, in

^{2}

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

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

*dead load*

**D =***earthquake load*

**E**_{ }=*specified compressive strength of concrete, psi*

**f**_{c}^{'}_{ }=*specified yield strength of transverse reinforcement, psi*

**f**_{yt }=*live load*

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

**L**_{r}_{ }=*nominal flexural strength at section, in.-lb*

**M**_{n }=

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

_{ }=

**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**_{ }=*strength of a member or cross section required to resist factored loads or related internal moments and forces in such combinations as stipulated in*

**U**_{ }_{ }=**ACI 318-19**

*nominal shear strength, lb*

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

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

**W**_{ }=*strength reduction factor*

**ϕ =****Required Strength**

Required strength is calculated in accordance with the factored load combinations in Load Factors and Combinations title.

Reinforced concrete walls with rectangular, I, T, L, U or C crossection are modeled with finite elements (shells) containing degrees of freedom for both in-plane and out-of-plane displacements. The resultant of the finite element joint forces are obtained as equivalent internal force (* M_{u}*,

*) at the cross-section gravity center, based on shear wall required strength and design strenth calculations.*

**P**_{u}The wall shear design is applied leg by leg for each of the design load combination. The factored shear force, * V_{u}* of the leg is determined and compared with design shear strength

**ϕV**_{n.}**Design Strength**

Design strength at all sections should be satisfy all conditions given below;

**ϕP**_{n}≥ P_{u}**ϕM**_{n}≥ M_{u}**ϕV**_{n}≥ V_{u}

Strength reduction factors * ϕ* is determined according to using

**ACI Table 21.2.2**

**.**Interaction between load effects is considered.

* P_{n}* and

*is calculated in accordance with Axial strength or Combined Flexural and Axial Strength title.*

**M**_{n}