# Column Axial Force Control

It is automatically controlled that the smallest cross section size of rectangular columns is not less than 300 mm and that the diameter of circular columns is not less than 350 mm.

By using the gross cross-sectional area of the column,

*A*_{c},*N*_{dm}, the largest of the axial pressure forces calculated under*G*+*Q*+*E*, it is automatically checked whether the condition*A*_{c}≥*N*_{dm}/(0.40*f*_{ck}) is met .

**ICONS**

**A _{c }**= Gross cross-section area of the column

**E**= Earthquake effect

**Q**= Live load effect

_{ }**G**= Constant load effect

_{ }**N**Considering the live load reduction coefficients defined in TS 498,

_{dm}=*G*and

*Q are*vertical loads and

*E*earthquake effects. Maximum of axial compressive forces calculated under joint effect

*G*+

*Q*+

*E*

**f**Characteristic cylinder compressive strength of concrete

_{ck}=**According to TBDY 7.3.1.1** , the smallest cross section size of rectangular columns should not be less than 300 mm and the diameter of circular columns should not be less than 350 mm. This condition is automatically checked and necessary information is provided.

**Column Axial Force Control**

**Depending on the TBDY** column cross-sectional area and concrete class, the axial force acting on the column is limited.

**7.3.1.2 -** The gross cross-section area of the column, *N *_{dm} , taking into account the live load reduction coefficients defined in TS 498, the joint effect of vertical loads *G* and *Q* and *E* earthquake effect is the maximum of axial pressure forces calculated under *G* + *Q* + *E.* larger, it will satisfy the condition *A *_{c} ≥ *N *_{dm} /(0.40 *f *_{ck} ).

It is checked whether the greatest axial pressure force N _{dm} under earthquake and vertical loads is less than 0.40 *A *_{c} f _{ck }.

*A _{c} ≥ N _{dm / (} 0.40 f _{ck} )*

If the condition is not met, the column area (A _{c} ) or concrete class should be increased.

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