# Determination of Internal Forces

Load combinations for steel buildings are automatically generated by the program according to ÇYHTYEY 2018 and TBDY 2018 4.4.2 and 4.4.4.

According to TBDY 2018, a combination should be made for the earthquake effects calculated for each horizontal direction. One direction effect is combined with 30% of the other direction in these combinations.

Since there are no elements specified in TBDY 4.4.3.1 in the structural system of the building, the vertical earthquake effect is calculated with the following equation.

There are two different groups of load combinations for YDKT and GKT methods in Steel Structures Regulation, as per Seismic Regulation. If the YDKT method is selected for design,

*load combinations are*automatically generated by arranging the coefficient of G as 1.2 in equation 4.11.

If the GKT method is chosen for design, the following load combinations given in Chapter 9 are used.

(9.1a)

(9.1b)

(9.1c)

The acquisition of internal forces based on design will be detailed in the sub-titles.

**Next Topic**