Category Archives: Beam Bending

Evaluating text with units and finding the neutral axis

A few weeks ago a comment asked for guidance on finding the moment capacity of a reinforced concrete section.  This post will look at finding the depth of the neutral axis (NA) in a rectangular section, with a single layer of … Continue reading

Posted in Beam Bending, Concrete, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , , , , , | Leave a comment

Section Properties with MeshPY, including torsion and warping

I recently discovered robbie van leeuwen’s structural engineering blog, which has an open-source set of Python routines for calculation of section properties, including torsion and warping constants.  The program uses the MeshPY Library for generating the finite element meshes required … Continue reading

Posted in Beam Bending, Concrete, Excel, Finite Element Analysis, Frame Analysis, Link to Python, Maths, Newton, Numerical integration, NumPy and SciPy, Strand7, UDFs, VBA, xlwings | Tagged , , , , , , , , | 4 Comments

Composite Beam Spreadsheet Update 1.01

Following a comment here, I have modified the Composite Beam spreadsheet to correct the stage 1 stresses forces in the reinforcement as listed in Columns 6 and 7, when the tensile face is the top.  The output has also been … Continue reading

Posted in Beam Bending, Concrete, Excel, Newton, UDFs, VBA | Tagged , , , , , , , | Leave a comment

Stepping through 3DFrame

Following a recent comment this post looks at the code for setting up the stiffness matrix for a 3D frame, and how to step through any selected part of the code. The general procedure for setting up a 3D stiffness matrix, … Continue reading

Posted in Beam Bending, Excel, Finite Element Analysis, Frame Analysis, Newton, UDFs, VBA | Tagged , , , , , | Leave a comment

Setting up UDF Applications

Following a recent comment, this post looks at setting up a user defined function (UDF) on a blank worksheet, using the ConBeamU function as an example. To use a UDF, the VBA code for the function must either be included … Continue reading

Posted in Arrays, Beam Bending, Excel, Finite Element Analysis, Newton, UDFs, VBA | Tagged , , , , | 1 Comment

Stress increments in prestressed concrete beams

The two main Australian Standards covering prestressed concrete structures (AS 3600, Concrete Structures, and AS 5100 Part 5, Concrete Bridges) put a limit on the allowable increase in stress in reinforcement and prestressing strands and tendons, when the load increases from … Continue reading

Posted in Beam Bending, Concrete, Excel, Newton, UDFs, VBA | Tagged , , , , , , | 2 Comments

3DFrame update

The update to the Glob_to_loc3 and Loc_to_glob3 functions (and associated functions) has now been transferred to the 3DFrame spreadsheet, which will now give correct results when beams are defined in the global negative Z direction.  The revised spreadsheet (including full … Continue reading

Posted in Beam Bending, Excel, Finite Element Analysis, Frame Analysis, Newton, Strand7, VBA | Tagged , , , , , | 12 Comments