# Shear Strength of Beams

**ICONS**

**A _{c} =** Element full section concrete area

**b**Body width of beam

_{w}=**D =**Extra Strength Coefficient

**d =**Useful height of beam

**f**Characteristic cylinder compressive strength of concrete

_{ck}=**f**Design compressive strength of concrete

_{cd}=**f**Characteristic yield strength of longitudinal reinforcement

_{yk}=**f**Design yield strength of longitudinal reinforcement

_{yd}=**l**The free height of the column between the beams, the free span of the beam between the column or curtain faces

_{n }=**M**Positive or negative moment capacity calculated on the column face at the left end of the beam i , taking into account f

_{pi}=_{ck}, f

_{yk}and the strength increase of the steel

**M**Right end of the beam Positive or negative moment capacity calculated by taking into account the strength increase of f

_{pj}=_{ck}, f

_{yk}and steel on the column face in j

**M**f

_{ri}=_{cd}and f

_{yd}on the column or wall face at the left end of the beam i

**M**Moment of negative or positive bearing strength calculated according to f

_{rj}=_{cd}and f

_{yd}on the column or wall face at the right end j of the beam

**V**Contribution of concrete to shear strength

_{c }=**V**Load Shear force calculated under the combined effect of vertical loads and earthquake loads multiplied by their coefficients

_{d }=**V**Simple beam shear force resulting from vertical loads not multiplied by load coefficients in any section of the beam

_{dy }=**V**Shear force taken as basis in beam transverse reinforcement calculation

_{e }=**V**Shear force strength of beam section

_{r }=**TBDY Article 7.4.5. Shear Safety of Beams**

**7.4.5.1** - beams transverse reinforcement account mainly be received shear force, V _{e} , the action of the earthquake from left to right or right to left for the case to separately, and unfavorable result, **Eq. (7.9)** to be found **(Figure 7.9)** .

Moment capacities at the beam ends can be taken as M _{pi} ≈1.4M _{ri} and M _{pj} ≈1.4M _{rj} . If the sum of D and increased shear force calculated from the earthquake together with the vertical loads is less than V _{e} calculated by **Equation (7.9)** , this shear force will be used instead of V _{e} .

**The** shear force, V _{e} , calculated according to **7.4.5.2** - **7.4.5.1 will meet** the conditions given by **Equation (7.10)** . **If the** second condition in **Equation (7.10) is** not fulfilled, the earthquake calculation will be repeated by increasing the cross-section dimensions as necessary.

**7.4.5.3** - In calculation of beam transverse reinforcement, contribution of concrete to shear strength, V _{c} , shall be determined according to TS 500. However, in the calculation of the transverse reinforcement in the beam confinement zones defined in **7.4.4** , if the shear force consisting of only seismic loads is greater than half of the total shear force in seismic condition, the contribution of the concrete to the shear strength will be taken as V _{c} = 0. The contribution of piles to shear strength in frame beams will not be taken into account.

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