Supplier’s information
Page 240 OmniTrax Product Guide
Supplier’s information
Sealant materials
Sealants may be poured from a can, caulking or sausage gun, or pumping equipment for large
quantities. Consult the supplier for the appropriate format for the job and size. Materials may be
self-levelling (SL) or non-sag (NS). Generally if the site is very flat, the SL materials flow most
readily into the slot. However, if there is any slope, the material might run out of the slot or beneath
the backer rod and periodic dams made of backer rod may be needed during curing. An NS
material may be used but these materials are more viscous and hence harder to pour, and they
may need tooling. Pre-formed sealants avoid many of these chemical issues.
The following describes some of the specific sealant characteristics and provides sources of
supply for materials tested. Consult the manufacturer or local representative for specific
equipment recommended for installation, handling instructions and material safety sheets.
Willseal 150 (Illbruck, Minneapolis, MN, 800-274-2813) is a compressed, open cell polyurethane
tape impregnated with neoprene. It is furnished in 14 ft. rolls with a cross-section sized to expand
to, and tightly fill, the slot dimensions above the cable. It has an adhesive on one side to retain it
during the expansion. It is applied by hand via this sidewall adhesion, using a putty knife, and it
expands within several hours to form a compression seal. Double layers can be used for wider slot
areas at decouplers. In the preferred application it is sized to replace both the backer rod and
sealant in a single step however, this is slightly more costly in materials. The advantage of using
this size is that it both provides the optimal seal shape and replaces one installation step. A note
when using pre-forms – since the seal depth is fixed, slot depth variations must be minimized
when cutting. A tolerance of no more than +/- 3 mm (1/8 in) is recommended to ensure the sealant
is recessed over its entire length. Since it arrives pre-compressed to 20% of its maximum width,
width variations are more tolerable.
DOW 888 and 890 Highway Joint Sealant (Dow Corning, Midland, NJ). These are single
component silicones, with 888 (grey) rated for concrete and 890 (black) rated for asphalt and
concrete. They can be applied by caulking guns or pumping equipment (see below). The SL
version is preferred. Curing will be slower in thick sections or at low temperatures, since air/
moisture is required. It provides a very good and durable bond to materials.
MOBAY 960 (Mobay Corporation, Pittsburgh, PA, (412) 777-2000). This is a single component
silicone that appears equivalent to DOW 888 with similar properties and application.
SEALEX (Meadows Sealtight Sealex Traffic Loop Sealant, W.R. Meadows, Elgin, IL, (708) 683-
4500). This is a low-cost, 2-component (black) material that is easily mixed in the can and poured
directly into the slots. It bonds to both asphalt and concrete but has a low bond strength. It is very
fluid so care must be taken that it doesn’t leak under the backer rod or out of sloping slots. Curing
has typically proven variable, from 1/2 hour to 3 days. It has been used extensively in less
demanding applications.
3M 5000 traffic loop detector sealant, comes in 1 liter sausages, 12 per case, requires pumping
equipment
To Next Page
Loading...
