6 posts tagged “Foundations”.
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.
Follow one gravity load from the slab through the beam, column and footing to the soil. Here is each handoff in the load path and why tracing it prevents errors.
A column's load is every floor it carries, added up. Here is how to find the axial load from tributary areas, stack it through floors, and factor it.
A bearing wall carries floor load as a line reaction per metre, not a point load. Here is how to take a wall down, what feeds its line load, and how it reaches the footing.
A footing carries the column above it plus its own weight. Here is how to find the load for bearing and for footing strength, using service and factored values.
Once you have a column's factored axial load, a quick required-area estimate gives a trial size. Here is the preliminary method for steel and concrete, with worked numbers.