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From: Victoria.Brinkly@dot.gov [mailto:Victoria.Brinkly@dot.gov]
Sent: Tuesday, May 01, 2012 10:39 AM
To: Nick.Artimovich@dot.gov
Cc: will.longstreet@dot.gov; rfaller1@unl.edu
Subject: RE: Guardrail on Soil Nail Walls

Thanks Nick.
I can’t remember if MWRSF was working with Central Fed Lands and TTI had some similar “rail on wall” design, or if it was vice versa. I do know the result was guardrail posts not set as close to the wall as our (western) geotechs were hoping for.

I’ve asked for more info on the sonotube installation and I’ll be interested to hear what Ron Faller thinks of this situation.

Tori

From: Artimovich, Nick (FHWA)
Sent: Tuesday, May 01, 2012 8:04 AM
To: Brinkly, Victoria (FHWA)
Cc: Longstreet, Will (FHWA); Ronald K. Faller (rfaller1@unl.edu)
Subject: RE: Guardrail on Soil Nail Walls

Tori,
I know you don’t have an extra inch to work with in that situation, but I am concerned that there is not enough embedment for the posts. The sonotubes might be a good way of installing the posts, but it does not appear that there is enough soil behind the tubes to resist the impact forces on the guardrail.

I am copying Ron Faller of the Midwest Roadside Safety Facility on this as they recently completed a project to design the Midwest Guardrail System to be  placed at the top of a gabion wall – not too dissimilar to the Agness Road situation in the photos you sent. Western Direct Federal may be able to contract with MWRSF to adapt a guardrail system for these situations.

There is also research recently completed and underway to design barriers for the top of reinforced earth walls. I am not familiar with the details, but I believe they need a concrete barrier with a moment slab to be able to perform effectively.
Nick

Nicholas Artimovich, II
Highway Engineer, Office of Safety Technologies
Federal Highway Administration HSST
1200 New Jersey Avenue SE, Room E71-322
Washington, DC 20590
email: nick.artimovich@dot.gov
phone: 202-366-1331
fax:      202-366-3222
web: http://safety.fhwa.dot.gov

From: Brinkly, Victoria (FHWA)
Sent: Tuesday, May 01, 2012 10:45 AM
To: Artimovich, Nick (FHWA)
Subject: Guardrail on Soil Nail Walls

Hi Nick…have you ever heard of any issues with guardrail on soil nail walls? Or the process the contractor outlined in photos below?
In theory it seems similar to the post in rock detail, but there’s not much info below on the size of the sonotubes or the material used for backfill.

Tori

From: Ulrich, Malcolm A (FHWA)
Sent: Tuesday, May 01, 2012 7:33 AM
To: MOEN, Margaret L (FHWA); Dissen, Charles (FHWA)
Cc: Brinkly, Victoria (FHWA)
Subject: FW: DSR sites on the Agness - Powers Road

FYI – would this system be acceptable? Doubt there has been crash testing, but…………

From: Bryan Wavra [mailto:bryan@gsi3.com]
Sent: Monday, April 30, 2012 7:53 PM
To: Ulrich, Malcolm A (FHWA)
Subject: RE: DSR sites on the Agness - Powers Road

Malcom,

Our MP 20.3 stabilization concept will incorporate a soil nail wall/buttress down the slope about 15 to 20 feet.  Therefore, guardrail could be installed without penetrating shotcrete or subsurface soil sails.  A rather minor addition to the scope of work if so desired.

We regularly install guardrail in circumstances where the wall is in close proximity to the travel surface. In these cases, sonotubes are cast into the shotcrete and backfilled with sand to facilitate guardrail installation. The following photos illustrate this process:









I met Chuck Dissen at the site during my reconnaissance.  I mentioned, as indicated in our proposal, that we are willing to drill a few exploratory borings at MP 13.1 and MP 15.1 Pro Bono to aid in the drafting of proposals to better stabilize those locations.  FHWA would of course be invited to observe the borings to collect data as well.  Sampling won’t be possible but we will be able to distinguish relative the relative consistency of the underlying soil….worthwhile information for sure.

The slides at MP 47.8, 48.0, and FS 3348 have all resulted in loss of road width.  We can fix these as well and would include a GRS (GCS) wall to regain road width.  We will work up proposals for your consideration.

Please feel free to reply or call me with further questions.

Best regards,
Bryan


Bryan Wavra, P.E.

Mobile (503) 999-4187
bryan@soilnaillauncher.com



From: Malcolm.Ulrich@dot.gov [mailto:Malcolm.Ulrich@dot.gov]
Sent: Monday, April 30, 2012 7:21 PM
To: Bryan Wavra
Subject: RE: DSR sites on the Agness - Powers Road

Bryan,

Thanks for making the site visit and proposal for the Agness Road slide.
One question that has come up is the width and other specifics needed for guardrail installation along a nailed wall.  What considerations and recommendations for guardrail are included in your design?


Malcolm Ulrich
Geotchnical Team Lead
610 E Fifth Street
Vancouver, WA 98661
malcolm.ulrich@dot.gov
360.619.7816 Office
360.607.4503



From: Bryan Wavra [mailto:bryan@gsi3.com]
Sent: Tuesday, April 24, 2012 9:15 PM
To: Ulrich, Malcolm A (FHWA)
Subject: RE: DSR sites on the Agness - Powers Road

Malcom,

I was able to locate these slides in google earth and have gps coordinates so I think I am in good shape….although more information is certainly a bonus.   It appears as though these slides are at least in the vicinity of the Agnes Road  slide and should be able to stop by this week while I am down south.

The Hurricane Ridge Road shoring project certainly sounds intriguing.  It may be tough to get to your office before the end of the day tomorrow but my flight to Billings doesn’t leave until 1 p.m. on Monday (April 30th) and could meet you that morning. It would also give me a chance to go over our proposal and concept for Agnes Road…perhaps in the company of the Contracting Officer. In the meantime, any information you may have readily available to send over by email would give me a chance to review.

It was a pleasure meeting you today.

Best regards,
Bryan


Bryan Wavra, P.E.

GeoStabilization, Inc.
Phone:  503-999-4187
www.geostabilization.com

a Soil Nail Launcher, Inc. Partner Company
www.soilnaillauncher.com


From: Malcolm.Ulrich@dot.gov [mailto:Malcolm.Ulrich@dot.gov]
Sent: Tuesday, April 24, 2012 7:14 PM
To: Bryan Wavra
Subject: DSR sites on the Agness - Powers Road

Bryan, here are the milepost locations: FSR 33 MP 47.6 and FSR 3348 MP 0.2.  These two sites are reportedly within ½ mile of each other. The map that was sent to me is rather crude, just a general area circled in red that I assume encompasses both sites.  I will see if I can get more precise locations for you and a better map as well, in the event that you can work site visits into your schedule for your trip south later this week.

I should have thought of this when you were here today:  I have another project that I would like to get your opinion about, one where we need temporary shoring at the base of a 160 foot long fill slope.  The shoring is needed in order to excavate and replace 25 feet at the outlet end of a long culvert (30 inch diameter) before lining the whole pipe.  The site is on the Hurricane Ridge Road in Olympic National Park, a few miles south of Port Angeles. I am thinking that launched nails might be an effective tool for ensuring stability of the excavation.  One of our geotechs has visited the site and has done an analysis of the  site based on  assumed/interpreted soil parameters.  I could send you some details via email or perhaps next time you pass through, maybe on your way back from Seattle (?) this week, I could describe the project directly to you.  Access is difficult and the work space will be very constricted as the fill pinches down into the gully where the pipe is located.  Let me know if you will have time to talk this over, and if it just won’t work this week I’ll plan to email you a plan sheet of the site  and we can discuss by phone.


Thanks.


Malcolm Ulrich
Geotchnical Team Lead
610 E Fifth Street
Vancouver, WA 98661
malcolm.ulrich@dot.gov
360.619.7816 Office
360.607.4503
 

MwRSF conducted the research on the wire-faced MSE wall and configured a non-blocked, steel-post MGS for use. Our final recommendations included a minimum lateral placement from outer edge of 4 ft 9 in. based on post embedment 1 ft away from 3-ft wide wall facing fill (larger stones).

TTI conducted an NCHRP study to develop guidelines for rigid barriers used on MSE walls, including recommendations and details for using configuring moment slabs. The Phase II effort is in progress to extend the guidelines to TL-4 and TL-5.