The revised version of the code reads an XML data file, this file contains names of structural sections and the resistance to bending (phi.Ms) in units of kNm. The file can be added to if needed, it already contains, Cee's, RHS, SHS, UB, UC, PFC's.
It doesn't contain back to back Cee's, such are not really required. As far as the program is concerned the bay spacing is the load width of the individual portal frame. The load width of a frame can be found by halving the distance to each frame either side of the selected frame and summing. For cold-formed steel sheds with frames at 3m centres the load width of a typical frame is 3m. The load width of the end frame is 1.5m. Often for sheds made from hot rolled steel the typical frames are UB's with the end frames made from PFC's: not always practical has it hinders extending the building, and there is extra detailing merely for two frames. Any case it gives the basic idea, the internal frames can be I-sections formed from back to back Cee's and the end frame can be a single Cee. Knowing that a single Cee has a load width of 3m, then back to back Cee's form a frame with a total load width of 6m, the back-to-back frames can therefore be placed at 6m centres, whilst a single Cee can be used for the end frame. Therefore check frame for load width of 3m (bayspace = 3m) for a single Cee rather than the back-to-back Cee's at 6m centres.
It is also to be noted that whilst a given section may be structurally strong enough, it may not be practical to make an adequate moment connection between the rafter and column.: such check is not made by the application. Other issues not checked are the deflections of the frame.
The prime purpose of the application is to determine what is not suitable and reject immediately, whilst that considered suitable by the application requires further structural design.
To keep the input form simple, there are many assumptions made in the background. The assessment made by the application will not match my height/span charts as I adopted internal pressure coefficients of -0.65 and +0.7 for this application, but -0.3 and +0.4 for the charts.
I have a larger Engine application, which I am in the process of also translating from Delphi to vb.net and from AS1170.2:1989 to AS1170.2:2011, makes fewer assumptions but has more input screens and requires connection to a database of section properties, it also generates scripts (.scr) for AutoCAD LT. The original purpose of EngineLT was to severe the original programme from the Borland Database Engine (BDE), as it seemed far too complicated setting up on some other computer.
The application can be obtained here: vbEngineLT.zip
- [14/01/2015] Original
- [23/04/2016] Changed downlinks to MiScion Pty Ltd web Store