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16 Computer Programs in Vibration Analysis
listing of the subroutine is given in the computer program of Table 16.3. All the
output statements are in the main program.
16.4.1 A Plane Frame Problem
A portal frame structure shown in Fig. 16.1 has been analysed by the computer
program given in Table 16.3.
As such in order to use the computer program for the analysis of plane frame,
constraints have been put in the boundary conditions along the out of plane direction.
The node numbers and the member numbers have been indicated in Fig. 16.1. The
displacement labels are related to the nodes. Total degrees of freedom in the computer
program are the total number of nodes in the structure multiplied by the degrees of
freedom per node. It can be seen in Fig. 16.1 that each member of the frame has been
divided into four elements. The input data of the problem is given in Table 16.4.
Output file has been presented in Table 16.5.
It may be mentioned that Table 16.3 contains the computer program of the space
frame.
Fig. 16.1 A plane frame