Continuing from: Frame Analysis with Excel – 6; Beam end releases and actions
Download Frame4.zip – the download file includes complete open source code.
Two more refinements have been added to the frame analysis spreadsheet:
- The stiffness matrix has been revised to take account of shear deflections for members where the shear area and shear modulus are provided.
- It is now possible to apply displacements and/or rotations to supports. Fixed freedoms are specified with “F”, or enter the support deflection in the appropriate units, or rotation in radians.
In addition a plotting routine has been added to plot the frame, with or without scaled deflections.
Shown below are results for an example frames, with results from the same frames analysed in Strand7, and plots of the deflected shape (scaled by a factor of 20) from the spreadsheet and Strand7:
Truss input and output added 30 Jan 10:
Member end releases are specified by entering a 1 in the column for the freedom to be released. A truss can be modelled by releasing the rotational freedom at both ends of each truss member (M1 and M2). Input and results for a simple truss are shown below. Note that all the members have zero moment at both ends, and the rotations (in radians) at each end of each beam are reported. The end release table headings in the spreadsheets in Frame4.zip have been modified to clarify the reqired input.