Hi all, I have a quick question that hopefully somebody can clear up for me.
I am designing a gravity retaining wall (gabion) and determining the lateral earth pressures.
I have created a couple of models using Maccaferri software but am doing some hand calculations because I'm a new engineer and need to understand why this software is spitting out what it is.
I've found that when determining the k values using the Coulomb method, the friction angle between the wall and soil affects the system quite dramatically (obviously, because it helps both overturning and sliding). Can somebody point me in the direction of a good reference for estimating this value? I have read on the internet that it depends on a number of variables but as a rule of thumb it is generally 0.5 to 0.75 the soil friction angle, but have seen it vary from this in examples. I have also noticed that the software I'm using it simply takes it as the internal soil friction angle,and when there is a backfill incline, it subtracts this angle from phi. Is this method too liberal?
Also, does a geotextile material change this value?
Obviously a more experienced engineer is going to review and sign off on this design, but I'm on my own for a little while. Thanks!
I am designing a gravity retaining wall (gabion) and determining the lateral earth pressures.
I have created a couple of models using Maccaferri software but am doing some hand calculations because I'm a new engineer and need to understand why this software is spitting out what it is.
I've found that when determining the k values using the Coulomb method, the friction angle between the wall and soil affects the system quite dramatically (obviously, because it helps both overturning and sliding). Can somebody point me in the direction of a good reference for estimating this value? I have read on the internet that it depends on a number of variables but as a rule of thumb it is generally 0.5 to 0.75 the soil friction angle, but have seen it vary from this in examples. I have also noticed that the software I'm using it simply takes it as the internal soil friction angle,and when there is a backfill incline, it subtracts this angle from phi. Is this method too liberal?
Also, does a geotextile material change this value?
Obviously a more experienced engineer is going to review and sign off on this design, but I'm on my own for a little while. Thanks!