The Silicoflex System consists of an inverted ‘V’ shaped, preformed, extruded silicone rubber seal, with a single component silicone locking adhesive and a primer. Two beads of silicone locking adhesive are used; one above and one below the silicone rubber seal to ensure a tenacious, water-tight and continuous seal. The system also comes with a single part silicone adhesive and a primer which creates a tremendously strong bond to the joint header. Silicoflex is used in both new construction with an armoring system or without. The system has been used heavily in bridge preservation activities and has been installed on hundreds of bridges and highways worldwide.
By selecting one of four individual Silicoflex glands any joint ranging from 0.5″ to 6.5″ will be sealed. The ability of the system to bond to new or existing steel extrusions, concrete, or elastomeric concrete joint headers makes it the most versatile system on the market today with an incredible track record of performance and longevity on existing installations that are over 20 years old on major highways across the US.
Silicoflex was installed on the approaches to the Golden Gate Bridge
Low Stress Design
During normal cyclic movement, the Silicoflex seal is not in tension due to its folded inverted “V” shape. This reduces stress on both the seal and the adhesive and eliminates the possibility of cohesive failure typically found in field molded sealants.
Large Movement Range
Silicoflex is manufactured in three different sizes which cover the full range of movements typical of single cell joint openings.
Silicoflex will remain flexible in almost any environment. The material stability temperature range for Silicoflex is -60° F to +350° F.
Ultraviolet Radiation and Ozone Resistant
The Silicoflex seal is comprised of an inorganic base silicone, which means it is highly resistant to the damaging effects of ultraviolet radiation and ozone attack. This resistance is far superior to organic rubbers commonly found in other joint sealing systems which degrade due to U.V. exposure.
Silicoflex will bond equally well to steel, concrete and elastomeric or polymer concrete surfaces. Silicoflex can also be used to reseal failed strip seal joints and works well with irregular, tapered and spalled joint openings. These features make Silicoflex ideal for maintenance and retrofit projects.
Silicoflex applications installed in the mid-1990’s are still performing effectively to this day.
Fast and Simple Installation
After sandblasting (if necessary) and priming, installation time is about 15-20 minutes per lane. 30 – 60 minutes after the installation is complete, the lane can be reopened to traffic.
In the event of a puncture, Silicoflex can be easily repaired using the silicone based locking adhesive. With more severe damage, locally damaged pieces can be removed and new pieces can be spliced in.
Debris Friendly, Self Cleaning Design
The inverted “V” shape directs debris to the edges of the seal where it is bonded and fixed. During cycling, debris is channeled upwards thereby reducing the chance of punctures. Other systems with “V” shaped seals direct debris towards the unsupported center, making it much more susceptible to punctures from debris.
Field Spliceable and Directional Changes
If required, the Silicoflex gland can be bonded to itself by using the same silicone locking adhesive. This permits installations lane by lane or rapid custom tailoring of the gland to go up and around curbs and parapets.
⇒For newly primed steel joint installations, wipe vertical faces of joint clean with a rag saturated in denatured alcohol – no sandblasting is necessary. For new concrete joint installations, roughen concrete surface and wipe vertical faces of joint clean with a rag saturated in denatured alcohol. Roughening can be done by sandblasting, wire brushing or other mechanical methods approved by RJ Watson. For joint seal replacements to existing joints, sandblast the vertical faces of the joint and wipe clean with a rag saturated in denatured alcohol.
⇒Mix together A and B components of Primer using a hand or drill mixer. Apply to the vertical joint interfaces.
⇒Unroll Silicoflex seal, place adjacent to joint opening and clean the seal with a rag saturated with denatured alcohol.
⇒Using a jumbo size (29 oz) caulking gun, place a 1/2” diameter bead of Silicoflex Locking Adhesive to both sides of the vertical face of the joint. This bead of adhesive should be placed at least 1” below the top of the joint elevation.
⇒Insert the Silicoflex seal into the joint, initially placing it above the first bead of locking adhesive. Gently ease the Silicoflex seal downward while maintaining contact of the sides of the seal to the joint header. Position the Silicoflex seal to the proper depth, which is when the top of the seal is at least 1.0” below top of road surface.
⇒Apply a second bead of locking adhesive along each side of the Silicoflex seal, to the top of the serrations, and no higher. This second bead of adhesive should be in contact with the Silicoflex seal and the joint face.
⇒The locking adhesive must be ‘tooled’ at least twice with a tongue depressor to ensure complete contact with the joint face.
⇒Allow 60 minutes before allowing traffic over a newly installed Silicoflex seal, unless directed otherwise by an approved representative. Vertical curbs, directional changes and field splices require the Locking Adhesive as a bonding agent.
The recommended minimum air/surface temperature to install Silicoflex is 40° F. The joint surface must be completely dry before installing Silicoflex. Silicoflex should not be installed immediately after precipitation or if precipitation is forecast for the day. Joint preparation and installation of Silicoflex must be done during the same day. Traffic must not be allowed to pass over a sandblasted and primed joint. R.J. Watson employs qualified technical representatives who can provide hands-on training for installers of Silicoflex. It is recommended that this service be used by first time installers. Please call our office to schedule a technical representative to be at your jobsite.