Simple Span, Uniform and Point Loading, By Load Type, Expanded Deflection Description

Our previous example introduced the concept of breaking each member down into segments and looking at the deflection at each segment location.  This spreadsheet expands on that method in two ways:

  • Deflection is checked at each segment

  • Bending stress is checked at each segment

If you recall the extent of calculation required for the simple, uniform load case, then it will not surprise you to know that checking deflection and stresses for six additional loads means that many more formulas fill the columns beyond line "J".  Go have a look.  Note that I have moved the deflection calculations down a page to minimize the horizontal span of the spreadsheet.  You can also see how each of the concentrated loads contributes to the total moment and deflection.

Examples of point loads are:

  • Interior partition walls

  • Sprinkler pipe mains

  • Package air conditioners hung from the roof joists

  • Suspended walls and soffits

A small diagram of all loads on the member will be helpful.  Assign left and right supports and enter the distance from the left support to each point load in the column provided.  Remember, change only those values in BOLD (in the yellow highlighted areas).