Load paths
UDL on a beam from tributary area
Turn a floor pressure into a uniform line load on a beam: multiply the tributary width by the load. Here is the method, beam self-weight, and the two-way equivalent UDL.
Sam Rivera··5 min
Load paths
How to calculate beam reactions from a slab
A slab loads a beam, and the beam passes that load to its end supports as reactions. Here is how to find them by statics, for uniform, triangular and trapezoidal loads.
Elena Marchetti··4 min
Fundamentals
Concrete slab self-weight calculation
Slab self-weight is thickness times density. Reinforced concrete is about 25 kN per cubic metre, so a 150 mm slab weighs about 3.75 kN per square metre. Here is how to get it right.
Sam Rivera··4 min
Codes & standards
Typical floor live load values by occupancy
Floor live load depends on use, and codes set minimum values by occupancy. Here is a reference table for offices, homes, retail, storage and more, in kPa and psf.
Sam Rivera··4 min
Load paths
How to do a structural load takedown (step by step)
A load takedown traces gravity loads from the slabs down to the foundation. Here are the five steps, a worked column, and the checks that catch errors.
Elena Marchetti··5 min
Load paths
Foundation reactions from a load takedown
The foundation reactions are where a takedown ends: the load each column and wall delivers to the ground. Here is how to read them and turn them into foundation design loads.
Elena Marchetti··4 min
Workflow & tools
Load takedown: spreadsheet vs software
Spreadsheets are flexible and free but slow on geometry; software automates tributary areas and stacking. Here is an honest comparison and when each one wins.
Elena Marchetti··4 min
Workflow & tools
How to read a structural floor plan
A structural floor plan tells you the grid, the supports, the spans and the loads. Here is what each element means and what to extract for a load takedown.
Elena Marchetti··5 min
Workflow & tools
Tribby3d alternative: StructLoads compared
Looking for a Tribby3d alternative for tributary areas and load takedown? StructLoads is a free, browser-based option. Here is an honest comparison of the two.
Elena Marchetti··4 min
Load paths
What is a transfer beam?
A transfer beam carries a column or wall that stops part-way down and redistributes its load to supports below. Here is what it does, why it is used, and how load flows through it.
Elena Marchetti··4 min
Codes & standards
Roof live load vs snow load
A roof carries both a minimum roof live load and a snow load, and the larger governs. Here is the difference, how each is found, and which one to design for.
Sam Rivera··4 min
Load paths
Lintel load calculation, explained
A lintel carries the wall and floor above an opening. Here is how to find its load, the triangular masonry-load idea, and a worked example for a door or window head.
Sam Rivera··5 min