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Fountain Park 1-LR 930811Information About Silicone Sealants DESCRIPTION DOW CORNING® 890-SL self-leveling silicone joint sealant for asphalt is a one-part, cold-applied, easy-to-use, self-leveling silicone material that cures to an ultra-low-modulus sill- cone rubber upon exposure to atmos- pheric moisture. The cured silicone rubber remains flexible over the entire temperature range expected in pave- ment applications. Asphaltic paving materials have Iow tensile strengths. This requires a sealant that can seal the joint while placing only minimal stress on the asphaltic joint face. Because of its ultra-low-modulus characteristics and good extension/ compression recovery (+100/-50 percent of original joint width), DOW CORNING 890-SL self-leveling silicone joint sealant for asphalt gives outstanding performance in highway, airport and bridge joints in which extreme movement occurs. DOW CORNING 890-SL self-leveling silicone joint sealant for asphalt is designed to perform as a durable joint seal between asphalt and/or concrete pavements. Because of its ability to firmly adhere to asphalt and concrete pavements, DOW CORNING 890-SL self-leveling silicone joint sealant for asphalt is particularly suitable for long-term sealing of asphalt to concrete shoulder joints. Additional uses include asphalt-to-asphalt and concrete-to-concrete expansion joints. (See Limitations.) DOW CORNING 890-SL self-leveling silicone joint sealant for asphalt features: · Easy to use - self-leveling (no tooling ©1990 Dow Coming Corporation. All rights reserved. DOW CORNING® 890-SL SELF-LEVELING SILICONE JOINT SEALANT FOR ASPHALT Type ........................................................................................... Ultra-low-modulus silicone Cure ........................................................................... One part; cures at room temperature by reaction with moisture in air Special Properties ........................................................... Self-leveling, no tooling required, unprimed adhesion to asphalt and PCC pavements Primary Use ................................................................ Specially designed for sealing joints between asphalt shoulders and concrete pavements step), one-component, cold-applied, ready-to-use as supplied; dispensed directly from the bulk container into the joint by hand or with an air- powered pump. · All-temperature gunnability - consistency and self-leveling characteristics are relatively un- changed over normal installation temperature range. · Unprimed adhesion - primer is not required for bonding to asphalt or Portland Cement Concrete. For optimum adhesion, the surface must be clean, dry and frost-free. · Seals irregular surfaces - the TYPICAL PROPERTIES These values are not intended for use in preparing specifications or joint designs, but for comparison of rubber properties. As Supplied Color ................................................................................................................. Black Flow, Sag or Slump ............................................................................... Self-leveling Extrusion Rate, grams per minute ....................................................................... 400 Percent Solids, percent minimum ......................................................................... 97 Specific Gravity .............................................................................................. 1.3-1.4 Skin-Over Time, at 25 C (77 F), minutes ............................................................... 30 Cure Time, at 25 C (77 F), days ............................................................................. 14 Full Adhesion, days .......................................................................................... 14-21 As Cured - after 21 days at 25 C (77 F) and 50 percent RH Elongation, percent minimum ............................................................................ 1400 Joint Modulus, at 50 percent Elongation, psi maximum ......................................... 7 Joint Modulus, at 100 percent Elongation, psi maximum ....................................... 8 Joint Modulus, at 150 percent Elongation, psi maximum ....................................... 9 Adhesion to Concrete, minimum percent Elongation ....................................... +600 Adhesion to Asphalt, minimum percent Elongation .......................................... +600 Specification Writers: Please contact Dow Corning Corporation, Midland, Michigan, before writing specifications on this product. sealant's self-leveling characteristics. make it ideal for sealing irregular joint surfaces by providing adequate contact to the substrate without the need for tooling. · High movement capability - the sealant will perform in a continuous joint movement of +100/-50 percent. · Ultra-low modulus - the sealant stretches to 100 percent in the joint with very little stress on the bond line or joint wall. This maximizes the probability of a successful seal with continuous or gradual joint move- ment. Joint movement caused by temperature, shrinkage, traffic, etc., requires a sealant that does not strongly resist stress and/or shear. · Fully elastic - the sealant can be stretched to 100 percent or com- pressed to 50 percent of the joint width and held there. When re- leased, it will recover 95 pement or greater of the original dimension. The extension and/or compression can be repeated many times and the sealant will resume its original shape without splits or cracks. · Resilient - once cured, the sealant prevents stones and other non- compressibles from entering the joint by "squeezing" them out as soon as the force pushing the noncompressibles into the sealant is removed. · Good weatherability- its 100 per- cent silicone rubber is virtually un- affected by sunlight, rain, snow, ozone or temperature extremes. Most organic sealants stiffen in cold temperatures and soften in warm weather. Organics also degrade and crack in sunlight. · Cure time - typically, the sealant will have a skin-over time of one hour or less. With a recessed joint design, the road can be opened to traffic soon after sealing in most applications. · Long-life reliability - under normal conditions, cured sealant stays rubbery from -45 to 149 C (-50 to 300 F) without tearing, cracking or becoming brittle. USES DOW CORNING 890-SL self-leveling silicone joint sealant for asphalt is designed for sealing joints between asphalt and/or concrete pavements. Because of its ability to firmly adhere to asphalt and concrete pavements, DOW CORNING 890-SL self-leveling silicone joint sealant for asphalt is par- ticularly suitable for long-term sealing of asphalt-to-concrete shoulder joints. Additional uses include asphalt-to- asphalt and concrete-to-concrete expansion joints. (See Limitations.) DOW CORNING 890-SL self-leveling silicone joint sealant for asphalt can be used as the original sealant in new highway construction or as a remedial or repair sealant in old construction. In new construction, it provides a long-lasting seal that will prolong the life of the pavement and prevent water and noncompressibles from entering into the joint and damaging the pavement and foundation. For use in repair or remedial applica- tions where other joint sealing materials have failed because of excessive movement or poor weather- ability, DOW CORNING 890-SL self- leveling silicone joint sealant for asphalt can be used to seal irregularly shaped and/or spalled joints. These joints should be clean, dry and free of all old sealing compounds. LIMITATIONS DOW CORNING 890-SL self-leveling silicone joint sealant for asphalt is not recommended for continuous water immersion. It should not be applied in totally confined spaces where the sealant is not exposed to atmospheric moisture. The sealant should never be applied to wet or damp asphalt or concrete pavements or installed during inclement weather. New concrete must be allowed to cure and dry for at least 7 days of good drying weather. For each day of rain that occurs during that period, an additional day should be added to the 7-day drying time. For "Fastrack" or high early concrete mixes, please contact your Dow Corning Technical Representative. The sealant bead must be recessed below the highway surface to prevent abrasion from traffic and snow re- moval equipment. The asphalt and concrete pavements should be sound and without signs of deterioration. If the asphalt pavement shows signs of deterioration, sealing b,_ joint may result in further damage to the asphalt. Several variables can affect the suitability of an asphalt pavement for joint sealing, including thickness, mix type compaction, age and overall structural integrity of the asphalt pavement. In addition, pavements with poor base conditions, including numerous patches, misaligned slabs and mid- slab cracking, are not candidates for saw and sealing techniques~. Suitability of DOW CORNING 890-SL self-leveling silicone joint sealant for asphalt for sealing asphalt expansion joints should be determined by thoroughly testing the product in your specific applications. For further details, please contact your Dow Corning Technical Service Representative. Joints should be prepared by saw cutting and not routing. Routing of asphalt and concrete pavements can cause microfractures in the pavement that can lead to poor joint performance. HOW TO USE Ultra-low-modulus DOW CORNING 890-SL self-leveling silicone joint sealant for asphalt easily withstands extreme joint movement when properly applied. The sealant will withstand 100 percent extension and 50 percent compression of the original joint width. However, the recom- mended movement design is for +50 percent and -25 percent and not at the sealant limits. This difference ensures a successful seal when job site joint widths are different than designed widths. Therefore, the joint design dimensions should be less than the ultimate sealant capability. A thin bead of silicone sealant will accommodate more movement and result in less bond line stress than a thick bead. DOW CORNING 890-SL self-leveling silicone joint sealant for asphalt should be no thicker than 1/2 inch (12.7 mm) and no thinner than 1/4 inch (6.4 mm). Within these limits, the sealant width-to-depth ratio should be 2:1. In all cases, the sealant must be recessed below the road surface at least 1/4 inch with 1/2 inch recess ~Highway & Heavy Construction, June 1988, p. 53. TABLE I: RECOMMENDED BACKL ,4OD INSTALLATION (SHALLOW CUT)~ I 1/4 3/8 1/2 3/4 1 Joint Width Recessed Below Surface 1/4" 1/4" 1/4" 1/4" 1/2" Sealant Thickness 1/4" 1/4" 1/4" 3/8" 1/2" Backer Rod Diameter 3/8" 1/2" 5/8" 7/8" 11/4" Total Joint ~On road surfaces where grinding is planned at a later date, the sealant and backer rod should be installed so that sealant is approximately 1/4 inch below the road surface after grinding is complete. An additional small amount should be added to allow for surface imperfections on the bottom and to provide room for old sealant to pump up from below during rehabilitation work in the summer months. being acceptable in wider joints. (See Table I.) DOW CORNING 890-SL self-leveling Silicone joint sealant for asphalt is an easy-to-use, self-leveling sealant that does not require a separate tooling step as conventional, non-sag sealants do. Because the sealant is self-leveling, it cannot be used on vertical surfaces. Before attempting to seal joints in new asphalt, the asphalt must be given sufficient time to cool and to "cure," FIGURE I: GOOD JOINT DESIGNS so that damage will not result from sawing. This time will depend upon a number of factors, such as mix design, time of year for placement, geographic location and past experiences. The asphalt must also be completely dry prior to sealant installation. In new construction where the joint is a new cut, a shallow cut may be used where the backer rod is placed on the bottom of the joint. (See Figure I.) A shallow cut saves time and saw blades. STANDARD JOINT SHALLOW CUT JOINT FOR NEW CONSTRUCTION DESIGN IF GRINDING IS ANTICIPA TED 1. Joint width wide enough to accommodate movement. (For additional information on joint width, see papers by Spells and Klosowski, "Silicone Sealants for Use in Concrete Construction," Vol. 1, No. 1, American Concrete Institute, SP- 70, 1981; J.B. Cook, "Construction Sealants and Adhesives," Wiley-lnterscience, 1970; and J.M. Klosowski, "Sealants in Construction," Marcel Dekker, 1989.) 2. Joint sawed deep enough to allow backer rod/sealant placement and space for pumping of old sealant compounds. NOTE: This applies to standard joints only; void space beneath backer rod in new construction is not needed. 3. Proper backer rod placement. 4. Sealant installed to proper depth and width. 5. Sealant recessed 1/4 inch to 1/2 inch below pavement surface. 6. Depth of lowest slab determines the amount of recess required if grinding is anticipated; once grinding is complete, the sealant will have proper recess below the pavement surface. In repair or remedial work where previous sealant materials have failed, care should be taken to completely remove the failed sealant from the joint faces. A standard joint design is recommended in which the backer rod is slightly above the shelf. Extra space should be provided to allow for possible "pumping" of old failed joint sealant that may have fallen below the joint. When DOW CORNING 890-SL self- leveling silicone joint sealant for asphalt is used for sealing reflection cracks in asphalt pavements, additional joint preparation steps must be used. Cracks that have formed in the asphalt pavement must be totally removed by saw cutting. This can be accomplished by saw cutting along both sides of the crack, exposing freshly cut and sound asphalt joint faces. When DOW CORNING 890-SL self- leveling silicone joint sealant for asphalt is used to seal asphalt-to- concrete shoulder joints, care must be taken to ensure that the asphalt is completely removed from the concrete face to which the sealant will be bonding. This can be accomplished by saw cutting tightly along the con- crete. A fresh and sound joint face must also be prepared in the asphalt by saw cutting. DOW CORNING 890-SL self-leveling silicone joint sealant for asphalt is part of a system that must include the proper backer rod and proper installation procedures. Table I shows proper backer rod size for various joint widths based on closed-cell backer rods. The backer rod must form a tight seal against the joint faces. Since DOW CORNING 890-SL self-leveling silicone joint sealant for asphalt is a self-leveling product, a tight seal is TABLE Ih JOINT REQUIREMENTS Linear feet per gallon of DOW CORNING 890-SL self-leveling silicone joint sealant for asphalt for various joint widths. Sealant Minimum Backer Backer Rod Joint Bead Joint Rod Placement Estimated~ Width, Thickness, Depth, Diameter, Depth, Linear Inches Inches Inches Inches Inches Feet/Gallon 1/4 1/4 I 3/8 1/2 275 3/8 1/4 11/4 1/2 1/2 185 1/2 1/4 11/4 5/8 1/2 140 5/8 5/16 11/2 3/4 9/16 90 3/4 3/8 13/4 1 7/8 60 7/8 7/16 1% 1 11/16 45 1 1/2 2 11/4 3/4 35 >1 1/2 2+ 11/4 + 3/4 _ ~Volumes will vary depending on joint design, tooling, backer rod placement and waste. required to eliminate material by- passing the backer rod. Where irregularly shaped joints exist, backer rod that is open-cell with an imper- vious skin is recommended to ensure a tight fit. INSTALLATION When installing DOW CORNING 890-SL self-leveling silicone joint sealant for asphalt, it is critical that the joint be clean and dry prior to and during installation. Several procedures have been used in the past. However, experie~tce has shown that some are less reliable than others. Water blasting, grinding, routing and wire brushing are no longer acceptable cleaning methods. Instead, the following procedure is considered most reliable and is recommended for cleaning and drying the joint. 1. CI.ea.n all joints of contaminants and impurities to the depths at which the sealant and backer rod are to be installed. In remedial asphalt applications, the asphalt (shoulder) must be sound. This may require cutting, immediately followed by flushing with water to remove sawing residue. Flushing should be done in only one direction (forward) to reduce recontamination of the joint faces. After drying, at least the top inch of each joint face must be sandblasted to ensure a sound, clean surface for sealant application. Sandblasting should be performed in two passes (one for each joint face) with the nozzle held at an angle to the face and no more than 2 inches from it. Sandblasting should be performed in compliance with federal and local laws. Proper protective equipment must be worn. 2. Blow out the dust, loose particles and other debris from the joints in one direction only with oil-free com- pressed air. Surfaces must be sound, clean, dry, frost-free and dust-free, and can be checked by running a finger along the joint face in concrete. If a white, chalky dust appears on the finger, the joint must be recleaned. 3. Install the recommended backer rod in the joint. The backer rod may be either closed-cell expanded poly- ethylene foam or open-cell poly- ethylene foam with an impervious skin. The backer rod must form a tight seal against the joint faces. Since DOW CORNING 890-SL self-leveling silicone joint sealant is self-leveling, a tight seal is required to eliminate sealant from by-passing the backer rod. For irregularly shaped joints, backer rods such as SofTM Rod1 is especially well suited to form a tight seal. The backer rod permits appli- cation of the sealant at the desired depth and acts as a bond breaker to allow the silicone sealant to stretch freely with joint movement. See Table I for the proper depth. 4. Install DOW CORNING 890-SL self- leveling silicone joint sealant for asphalt in a continuous operation to ~As manufactured by AET Corporation. properly fill and seal the joint. (See Table II.) The nozzle used to install the sealant should be such that the joint is filled from the bottom up. Filling in this manner displaces air from the joint and eliminates the likelihood of creating air voids in the sealant. Do not overfill the joint. The sealant must be recessed below the pavement surface to prevent traffic abrasion. (See Figure I.) In case of an overfilled joint, excess sealant must be removed so that proper joint geometry and recess are maintain~Eo;maxi- um ~.~'m ~ a4,,ou~d be~ ~~ratUre above 4.4 C (40 F). For optimum adhesion, new concrete must be allowed to cure and dry for a minimum of 7 good drying days prior to sealant installation. For each day of wet or rainy weather, an additional day of dry weather must be added to the drying period. For "Fastrack" or high early concrete mixes, contact your Dow Coming Technical Representative. 5. DOW CORNING 890-SL self- leveling silicone joint sealant for asphalt will self-level and develop good contact with the joint surface without tooling. 6. Excess sealant may be cleaned from tools and equipment while in an uncured state with a commercial solvent such as xylol or a high-flash solvent. Use appropriate precautions with regard to fire hazards and eye and skin contact. (Use goggles and gloves, if needed.) 7. Joints that have been proF .. ,y recessed may be opened to traffic as soon as the installation equipment can be cleared from the traffic lane. NOTE: For complete installation instructions, see the DOW CORNING Silicone Pavement Sealants Install- ation Guide, Form No. 61-507. CAUTION Before handling sealant, read product and material safety data sheets for detailed use and health information. Direct contact with uncured sealant may irritate eyes slightly. Avoid eye contact. Do not handle contact lenses with sealant on hands. In case of eye contact, flush eyes with water for 15 minutes. Uncured sealant may cause injury if swallowed in large amounts. Do not put in mouth. If swallowed, obtain immediate medical attention. Toxicology studies indicate that repeated, prolonged overexposure to N-MA causes adverse reproductive effects in laboratory animals. Avoid breathing vapors. Do not use in poorly ventilated spaces. Avoid prolonged skin contact. KEEP OUT OF REACH OF CHILDREN. SHIPPING LIMITATIONS None. STORAGE AND SHELF LIFE When stored in original, unopened containers at or below 32 C (90 F), DOW CORNING 890-SL self-leveling silicone joint sealant for asphalt has a shelf life of 6 months from date of shipment. Keep containers tightly closed. PACKAGING DOW CORNING 890-SL self-leveling silicone joint sealant for asphalt is supplied in 29-fl oz (857-mL) dis- posable plastic cartridges, 4.5-gal (17-L) bulk pails, and 40-gal (151.4-L) bulk drums. MSDS INFORMATION A'I-I'ENTION: PRODUCT SAFETY INFORMATION REQUIRED FOR SAFE USE IS NOT INCLUDED. BEFORE HANDLING, READ PROD- UCT AND MATERIAL SAFETY DATA SHEETS AND CONTAINER LABELS FOR SAFE USE, PHYSICAL AND HEALTH HAZARD INFORMATION. THE MATERIAL SAFETY DATA SHEET IS AVAILABLE FROM YOUR DOW CORNING REPRESENTATIVE, OR DISTRIBUTOR, OR BY WRITING TO DOW CORNING CUSTOMER SERVICE, OR BY CALLING (517) 496-6000. WARRANTY INFORMATION - PLEASE READ CAREFULLY Dow Corning believes that the information in this publication is an accurate description of the typical characteristics and/or uses of the product or products, but it is your responsibility to thoroughly test the product in your specific application to determine its performance, efficacy and safety. Unless Dow Corning provides you with a specific written warranty of fitness for a particular use, Dow Coming's sole warranty is that the product or products will meet Dow Coming's then current sales specifications. DOW CORNING SPECIFICALLY DISCLAIMS ANY OTHER EXPRESS OR IMPLIED WARRANTY, INCLUD- ING THE WARRANTIES OF MER- CHANTABILITY AND OF FITNESS FOR USE. Your exclusive remedy and Dow Corning's sole liability for breach of warranty is limited to refund of the purchase price or replacement of any product shown to be other than as warranted, and Dow Corning expressly disclaims any liability for incidental or consequential damages.