In each step of the push analysis, displacements for each direction and mode are automatically calculated.
The increment of displacement of any (s) degree of freedom (or node) of the conveyor system for a typical n'th natural vibration mode in any i'th pushing step between two consecutive plastic joint formation, u sec (i) is expressed by the following equation are being.
The above equation can be expressed in the i'th repulsion step of the repulsion analysis for an earthquake in the (X) direction and as the displacement increment for a typical n'th natural vibration mode, Δu xsn (i) . Similarly, for an earthquake in the (X) direction, the modal displacement increment, Δd xn (i), and the mode shape amplitude can be written as Φ xsn (i) .
(X) and (Y) in the seismic line in the i-th thrust step, a typical n-th carrier system for natural vibration mode of any one (s) displacement increments of node, Δ is xsn (i) and Δ is ysn (i) the location The replacement values u xsn (i) and u ysn (i) can be calculated by the following equations.
With this process, the deformations of the structure for each mode are obtained at the end of the i th pushing step. These changes are then combined with the CQC rule, resulting in a modified system to perform modal analysis in the next step.