There is an excerpt in Reese's 'Analysis and Design of Shallow and Deep Foundations' which directly addresses your concerns. I will summarize the points below for everyone's reference:
1.) The decision to add skin and end bearing resistance for drilled shafts in rock needs to be made on a case...
jagti
The NHI Segmental Retaining Wall manual (2nd Ed) does address this case (Refer to section 2.5.4 Tiered Walls), as was previously noted by Boondog. The diagram shown in the NHI manual shows straps however paragraph 2.5.4 addresses how to modify the method for gravity walls.
I have also...
Re-emphasizing fattdads points, the borings need to be viewed in the context of site geology.
Based upon your comments you seem fairly certain that boulders will only be encountered in a certain area of the project over a very specific depth range. I would point out that you cannot know this...
I believe the 10% rule you are referring to usually is only applied to 'competent, massive rock'. Judging by your description this is not the case. Trying to backcalculate any parameters from that allowable bearing pressure is a waste of time.
A contractor who installs anchors in your project...
Thank you Boondog.
My office is actually reviewing a submittal from another firm. We are having this argument with designer on whether or not to use the cohesion.
When I couldn't find a clear answer in AASHTO, I ran a check in MSEW ver. 3.0. Curiously, the additional resistance from the...
JAE
At this point I am considering that the wall is sufficiently reinforced to act as a single mass. I am attempting to verify external stability of the MSE wall. The lateral earth pressure exerted by the material behind the reinforced zone must be resisted by frictional forces (and potentially...
To clarify:
If I calculate the factor of safety in sliding considering only the frictional resistance (W * tan phi), I would estimate a certain factor of safety (FS).
If I calculate the factor of safety considering both frictional resistance and cohesive resistance (W * tan phi + c * B), I...
For this particular wall, I cannot use the NCMA code since it will be within a highway corridor. I recall that even using that code the cohesion is partially reduced by some factor.
I am trying to verify the sliding resistance for an MSE Wall. The geotechnical report provides a friction angle and drained cohesion for the foundation soils. The recommendations from AASHTO (Sect. 11.10.5.3 and 10.6.3.4) and FHWA MSE Wall manual (FHWA-NHI-00-043) seem to indicate that only the...