I agree with the above responses. At some point you just have to tell the client that the options have been presented, and the client has to make the choice based on the risks you’ve informed them of. I have had a project that aggregate piers were used for the combined benefits of drainage and...
Modeling a pile group with an "I" shape (group of piles at the top and bottom of the "I", tied together). I'm looking for some insight as to if the results I'm seeing "make sense." This particular scenario has 1000k compression on the top of the "I" and 1000k tension on the bottom of the "I". As...
I expect if you do a refined analysis, the initial stress condition would be somewhere between the toe and the heel. Especially for small structure widths where the walls are not all that far apart.
In Massachusetts, MassDOT recently specifically directed on a project that only the overburden...
Reaching out to see if anyone has a good reference or training module for performing site specific seismic studies for Site Class F evaluation. Thanks!
FHWA and AASHTO LRFD Design manuals for lateral load analysis using soil-pile interaction, including modifiers to account for pile spacing. But, overall I agree with the above comment that this is not something that is quickly jumped into without any additional guidance.
Hello. I have a question regarding settlement calculations for a small bridge abutment. 20’ span with 6’ of soil above the footing bearing elevation at the toe and 16’ at the heel. Would you consider the 6’ to be Df or 16’? Certainly the 6’ would be conservative, but that Df results in...
What aspect of the design are you referring to? The elements themselves or the footing-pier interaction? In my experience the rigid inclusions foe geotechnical design are designed using conventional pile design (ie for settlement calculate settlement based on an equivalent sized footing...
Thanks Jrit. That is what I was expecting. In this case the contractor asked if we need to inspect the tank foundation subgrades. My take is that the tank designer should be responsible for that.
GeoEnv - the inspections are per section 17 of IBC. The statement lists the inspection services required for the project and is issued to the building inspector, but the designer of record. You’ll find examples if you search google for statement of special inspections. However, in my example of...
Thanks Dave - maybe if I reword / clarify this a bit - if the project falls under IBC and therefore there is a need for Special Inspections, a Statement of Special Inspections is prepared that lists the Design Professional in Responsible Charge.
The owner has an engineer for the overall...
A general question on engineer’s responsibility. For a project where a geotechnical engineer performs borings and then those borings are provided to another entity (water tank designer-builder), who is then the geotechnical engineer of record? If the tank designer designs the foundations and are...
Thank you SlideRuleEra. So it sounds like your suggestion on a better approach than sheets would be open cut with a robust dewatering system, while considering/managing the effects of drawdown on neighboring properties.
I'm looking at a project that requires excavation to about 25 feet depth over an area of about 20,000 sf, with bedrock at higher than the target depth (let's say rock at 20 feet on average). Groundwater is at about 5 feet. For this scenario, I'm anticipating temporary SOE would be installed to...
60 kips. Although at 60 kips the very shallow 2' long lengths will obviously not work for bond or for rock mass. The will require about 8' long bond zones at 7" diameter to achieve 60 kips. But that is assuming the anchors would be passive anchors and would have an end nut or wedge like a...
I've been asked (as the geotechnical engineer) to consider the use of shallow rock anchors for resisting uplift of a buried structure resulting from buoyancy of the structure (structure below groundwater level). I would typically design the rock anchors according to FHWA prestressed rock anchor...
Thanks WesternJeb. Good questions. It is a delegated design. We will be providing the layout in plan view and various external loading magnitudes and from there it will be design-build via performance spec.
Hello All - I'm looking to see if anyone here has a secant pile wall specification I can use as a basis for preparing a project-specific specification. Any help would be greatly appreciated. Thank you.
