Hey guys,
I plan to take the PE exam, geotech depth, on October 2008.
So far, I have been trying to solve a couple of problems from several books. I have some questions regarding Prob 507 from the NCEES and prob 14 from the "Civil PE sample examination" book (By Linderburgh).
In the NCEES practice book, in prob 507 (geotech depth), I think there is something wrong with the solution.
I know that we need to solve it by using the chart that is given (DM7.1) and using the consolidation formula as well.
Since the consolidation formula involves both Initial vertical stress and stress increment, we need to find the stress increment from the chart. What I notice is that after the author computed the stress increment (delta sigma), he did not take into account that the water table was above the point of interest (the NC clay layer), so he was supposed to substract the water pressure from the stress increment, wasn;t he?
I know he did so when he computed the initial vertical stress, but I think he had to do it for computing the stress increment as well.
Anyone had the same problem?, please let me know
Regarding the "Civil PE sample examination" book (By Linderburgh), in prob 14, when computing the FS for the saturated clay slope, accordgin to Eq 40.28, you are supposed to work with gamma effective, But i notice that in the solution, the author uses gamma saturaded instead of the effective.
Anyone had the same problems?
Please let me know.
I plan to take the PE exam, geotech depth, on October 2008.
So far, I have been trying to solve a couple of problems from several books. I have some questions regarding Prob 507 from the NCEES and prob 14 from the "Civil PE sample examination" book (By Linderburgh).
In the NCEES practice book, in prob 507 (geotech depth), I think there is something wrong with the solution.
I know that we need to solve it by using the chart that is given (DM7.1) and using the consolidation formula as well.
Since the consolidation formula involves both Initial vertical stress and stress increment, we need to find the stress increment from the chart. What I notice is that after the author computed the stress increment (delta sigma), he did not take into account that the water table was above the point of interest (the NC clay layer), so he was supposed to substract the water pressure from the stress increment, wasn;t he?
I know he did so when he computed the initial vertical stress, but I think he had to do it for computing the stress increment as well.
Anyone had the same problem?, please let me know
Regarding the "Civil PE sample examination" book (By Linderburgh), in prob 14, when computing the FS for the saturated clay slope, accordgin to Eq 40.28, you are supposed to work with gamma effective, But i notice that in the solution, the author uses gamma saturaded instead of the effective.
Anyone had the same problems?
Please let me know.