RFreund
Structural
- Aug 14, 2010
- 1,881
Poulos and Davis present stress using 'elastic methods' for point loads and strip loads.
My question is - They present what I will call and unmodified Boussinesq solution for point/line loads.
However it appears that they present an equation for a strip load that does not match what an 'unmodified Boussinesq' solution would result in. Meaning it does not seem to be based on 'pure elastic theory' ( I may be wrong here). However it does seem to match the solutions that I have seen in other texts for the result of a strip load based on some modification.
I say this because if you take a finite number of point loads based on a distributed load i.e. you have a 1,000psf strip load so you break this into (10) 100lb point loads spaced 1' on center. Then find the pressure for each point load using unmodified Boussinesq solution for point loads and sum the pressures. This does not result in the same pressure as using the strip loading solution.
Additional assumptions - the strip load is using (poisson's ratio) v=0.5 which means that v=1.0 for the point load solution.
Bowels 4th edition talks about this as well.
Any thoughts on this or am I in error?
EIT
My question is - They present what I will call and unmodified Boussinesq solution for point/line loads.
However it appears that they present an equation for a strip load that does not match what an 'unmodified Boussinesq' solution would result in. Meaning it does not seem to be based on 'pure elastic theory' ( I may be wrong here). However it does seem to match the solutions that I have seen in other texts for the result of a strip load based on some modification.
I say this because if you take a finite number of point loads based on a distributed load i.e. you have a 1,000psf strip load so you break this into (10) 100lb point loads spaced 1' on center. Then find the pressure for each point load using unmodified Boussinesq solution for point loads and sum the pressures. This does not result in the same pressure as using the strip loading solution.
Additional assumptions - the strip load is using (poisson's ratio) v=0.5 which means that v=1.0 for the point load solution.
Bowels 4th edition talks about this as well.
Any thoughts on this or am I in error?
EIT
