Monday, January 27, 2014

Plane Frame Analysis with Graphics

I've now got the screen graphics back into plane frame application, which had been taken out to provide a command line application (cpframe) which can be run from with in other applications. This version I have named gpframe, for graphics plane frame its is still a DOS based application. When converted to run in Windows I will name it wpframe.

It can be called by typing the following in a command prompt:


It will then bring up a menu system which will allow selecting a file. (The file name needs to conform with 8.3 conventions, as does the folder structure where the file is located. Which messes up using it under "Documents and Settings\user name\My Documents". The files also need to be in the same folder as the application as it doesn't support moving around folders: the current working directory. The things we now take for granted, though never really a problem in DOS as always worked in the folder where the files were, and called the applications via batch files.)

Opening Screen
Main Menu
Plot Menu
Moment Diagram

Shear Force

Axial Force
On first look I did think the deflections were incorrect, with an expectation that the whole frame would sway to the right, but a check with Multiframe indicates similar deflection at the nodes, with an inward pull towards the centre of the frame from both sides. Which is where the Kleinlogel formula and associated diagrams are a useful reference for checking influence of individual loads. The formula typically give a single direction of loading (vertical, horizontal or normal) on a single element of a frame. Unfortunately I don't have the book with me. So I'm guessing (well slightly better than a guess) the vertical component of the wind load on the central gable frame has the net effect of pulling the frame inwards and exceeds the sway that would be produced by the horizontal components of load on the whole frame. If the central span was smaller then the behaviour would be different. It is something which can be assessed by creating additional models of the structure and looking at the influence of individual loads.

It can be downloaded here.

Users of the software must accept this disclaimer of warranty :
The software is supplied as is. The author disclaims all warranties, expressed or implied, including without limitation, the warranties of merchantability and of fitness for any purpose. The author assumes no liability for damages, direct or consequential, which may result from the use of the software.

Related Posts:

[27/01/2014] Original
[23/04/2016] Changed download links to MiScion Pty Ltd Web Store