Lomarandil
Structural
- Jun 10, 2014
- 1,897
So, I've been thinking about this a little while.
To determine the soil pressures at some depth below a triangular load, it seems very common to take influence factors from a Boussinesq or Westergaard chart for corner O. Multiply your influence factor by your load, and voila -- peak pressure.
(Or, split it into two triangular loads to check a point along the centerline of the loaded area, etc).
However, it seems to me that the corner of the loaded area is not necessarily the critical location. What if one were to analyze a point somewhere inside the triangularly loaded area by breaking that triangular load up and then using superposition?
To be more specific, I'd break a typical triangular load into three regions -- a triangular region from L=0 load to L=x (with load from 0 to P*x/L), a second triangular region from L=x to L=L (with load from P*x/L to P), and a rectangular region from L=x to L=L (with load P*x/L).
In the case I've checked, this results in soil pressures some 30-50% higher than the traditional check at corner O (usually about 10% back from the corner). Am I missing something?
Thanks!
To determine the soil pressures at some depth below a triangular load, it seems very common to take influence factors from a Boussinesq or Westergaard chart for corner O. Multiply your influence factor by your load, and voila -- peak pressure.
(Or, split it into two triangular loads to check a point along the centerline of the loaded area, etc).
However, it seems to me that the corner of the loaded area is not necessarily the critical location. What if one were to analyze a point somewhere inside the triangularly loaded area by breaking that triangular load up and then using superposition?
To be more specific, I'd break a typical triangular load into three regions -- a triangular region from L=0 load to L=x (with load from 0 to P*x/L), a second triangular region from L=x to L=L (with load from P*x/L to P), and a rectangular region from L=x to L=L (with load P*x/L).
In the case I've checked, this results in soil pressures some 30-50% higher than the traditional check at corner O (usually about 10% back from the corner). Am I missing something?
Thanks!
