# Coupling Beam Design.

Boundary Elements of Special Structural Wall requirements are met automatically

**International Design Codes**

* ACI 318-19 : *Coupling Beam Design (v12)

**TSC 2018 :**

**Notation in ACI 318-19**

* A_{ch } = *cross-sectional area of a member measured to the outside edges of transverse reinforcement, in.

^{2}

*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.*

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

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

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

*gross area of concrete section, in*

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

*total cross-sectional area of transverse reinforcement, including crossties, within spacing s and perpendicular to dimension*

**A**_{sh }=*, in.*

**b**_{c}^{2}

*cross-sectional dimension of member core measured to the outside edges of the transverse reinforcement composing area*

**b**_{c }=*, in.*

**A**_{sh}*width of compression face of member, in.*

**b**_{w }=*dimension of rectangular or equivalent rectangular column, capital, or bracket measured in the direction of the span for which moments are being determined, in.*

**c**_{1 }=*dimension of rectangular or equivalent rectangular column, capital, or bracket measured in the direction perpendicular to*

**c**_{2 }=*in.*

**c**_{1},*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}_{ }=

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

**s****=**center-to-center spacing of items, such as longitudinal reinforcement, transverse reinforcement, tendons, or anchors, in.

**s**_{o}**=**center-to-center spacing of transverse reinforcement within the length

*, in.*

**l**_{o}*nominal shear strength, lb*

**V**_{n }=*angle definin the orientation of reinforcement*

**α =**