DR16-02-CS180125
Request For Information
RFI No.: 001
Contractor:Ark Contracting Services, LLC Project:Grapevine Creek Bank Stabilization
Owner:City of Coppell Refer to Drawing/Spec:Sht. 5 & 6
Engineer:Teague Nall & Perkins Attachments:0
Problem Identification or Question:
If you refer to the Typical Section of Anchors on the wall sections, it states that the anchors are to be set at 15 degrees. In
previous projects with this height of walls and anchor lengths, we have always gone 30 degrees minimum. Is there a
specific reasoning for installing the anchors at 15 degrees?
Initiator of Request:Tiffany Rawls, ARK,PM Date:1.25.18
Suggested Resolution:
Set the anchors at a minimumof 30 degrees
Suggested Resolution By:Tiffany Rawls, ARK, PM Date: 1.25.18
Resolution
The project Geotechnical Engineer for Terracon recommended the anchors be placed at 15 degrees to be in compliance
with TxDOT Geotechnical Manual, Section ‘Tie-Back Wall Design’, page 6-9 which states tie-backs should be nearly
horizontal between 10 degrees and 15 degrees. The project Geotechnical report no. 94165306, Global Stability Analysis
Exhibit C-2was developed based upon anchors placed at 15 degrees to the horizontal and satisfactory results were
obtained.Contractor shall install anchors according toplans showing anchors placed at 15 degrees to the horizontal.
Reviewed By:Keith Burkholder, PE, TNP
Project Engineer:__Keith Burkholder, PE, TNPDate:1/26/18
Resolution By:______________________ Company / Section:______________Title:___________ Date:_________
Distribution:
Project ManagerOwnerFile
Construction ManagerOriginator
Office ManagerConst. Liaison Engr.,
DesignerContractor
O:\\PROJECTS\\CPL16346\\docs\\construction admin\\RFI's\\RFI 001.docx
03/2010