11
Revision D November 2022
Foundation/Anchoring
Warning:
It is the responsibility of the local DOT or appropriate highway authority
to ensure the assembly conforms to the AASHTO Roadside Design Guide.
Asphalt Installations
QuadGuard
®
Narrow systems with a Tension-Strut Backup may be temporarily installed in
construction zones on asphalt. Assemblies on Asphalt Concrete
(“A.C.”)
must provide a minimum
of 76 mm [3”] layer of asphalt over a minimum of 76 mm [3”] layer of
Portland Cement Concrete
(“P.C.C.”)
, 152 mm [6”] layer of asphalt over 152 mm [6”] layer of subbase, or 203 mm [8”] layer
of asphalt with no subbase.
Important:
Only 460 mm [18”] threaded rods,
utilizing Valtir approved adhesive,
can be used with asphalt foundations. Contact Customer Service for a complete
list of approved adhesives (p. 3).
Concrete Installations
For concrete installations, the QuadGuard
®
should be installed only on an existing or freshly
placed and cured concrete base (28 MPa [4000 psi] minimum). Orientation of the concrete base
and the attenuator must comply with the project plans or as otherwise determined by the project
engineer or appropriate highway authority.
The QuadGuard
®
may be installed on any of the following foundations using the specified
anchorage:
Foundation A: Concrete Pad or Roadway
Foundation: 150 mm [6”] minimum depth P.C.C.
Anchorage:
Approved adhesive
with 180
mm [7”] studs 140 mm [5 1/2”] embedment
Foundation B: Asphalt over P.C.C.
Foundation: 76 mm [3”] minimum A.C. over 76 mm [3”] minimum P.C.C.
Anchorage: Length of anchor required is 460 mm [18”] 420 mm [16 1/2”] embedment
Foundation C: Asphalt over Compacted Subbase (“C.S.”)
Foundation: 150 mm [6"] minimum A.C. over 150 mm [6”] minimum
C.S.
Anchorage:
Approved adhesive with 460
mm [18"] studs 420 mm [16 1/2”] embedment
Foundation D: Asphalt Only
Foundation: 200 mm [8”] minimum A.C.
Anchorage:
Approved adhesive with
460 mm [18”] studs - 420 mm [16 1/2”] embedment
Important:
Systems mounted on asphalt must be replaced and mounted on
fresh, undisturbed asphalt if more than 10% of anchors are found to be loose,
broken, or show signs of pull out. If 10% or fewer anchors are damaged, replace
the damaged anchors in the existing asphalt. Anchor bolts used on systems
mounted on asphalt must be inspected every six months. See Post Impact
Instructions and Maintenance and Repair instructions on page 59 and 60.
