crogmobulon
Active member
If you have this book, I could really use help resolving some issues with their solutions. I have edition 1, printing 1 and have added in the errata from the PPI site.
In the solution to problem 38, 2nd paragraph on page 49: they state that the change in head for both layers of soil is equivalent to the piezometric head at the base of the bottom layer. They originally had that as 15', but changed it to 12'. Wouldn't the sum of the changes in head be equal to the total difference in head from the figure which appears to be 15'? I tried solving for the head loss through the upper layer using equation 205.11 in Goswami's book where H is the total head dissipated across all layers, and got h1=4.9'. I guess it comes down to how H is determined from the figure for problem 38. What's your call?
I also have a problem with their solution to question 49 on page 54. For the overburden term where the water table is between the ground surface and the footing, they use: [γd(Df) + γw(Dw-Df)]Nq.
Df is the depth to the bottom of the footing from the ground surface.
Dw is the depth to the water table from the ground surface.
According to Goswami's and Das' books, this term should be [γ(Dw) + (γsat- γw)(Df-Dw)] Nq.
They give two different answers. The second one makes sense to me, but the one from the 6-Min. solution does not. There is nothing in their errata regarding this solution, but I just don’t see how theirs could be correct.
Any help would be appreciated.
In the solution to problem 38, 2nd paragraph on page 49: they state that the change in head for both layers of soil is equivalent to the piezometric head at the base of the bottom layer. They originally had that as 15', but changed it to 12'. Wouldn't the sum of the changes in head be equal to the total difference in head from the figure which appears to be 15'? I tried solving for the head loss through the upper layer using equation 205.11 in Goswami's book where H is the total head dissipated across all layers, and got h1=4.9'. I guess it comes down to how H is determined from the figure for problem 38. What's your call?
I also have a problem with their solution to question 49 on page 54. For the overburden term where the water table is between the ground surface and the footing, they use: [γd(Df) + γw(Dw-Df)]Nq.
Df is the depth to the bottom of the footing from the ground surface.
Dw is the depth to the water table from the ground surface.
According to Goswami's and Das' books, this term should be [γ(Dw) + (γsat- γw)(Df-Dw)] Nq.
They give two different answers. The second one makes sense to me, but the one from the 6-Min. solution does not. There is nothing in their errata regarding this solution, but I just don’t see how theirs could be correct.
Any help would be appreciated.