,
The harm of road cracks lies in water seeping into the subgrade through the cracks, causing the subgrade to soften and deteriorate, leading to a decrease in road bearing capacity, the formation of mud gushing and network cracking, and accelerating the damage to the road surface. If road cracks are not promptly treated with crack filling sealant, tape, or other repair materials, and the subgrade is infiltrated by rain or snowmelt, the long-term compaction by vehicles can result in subgrade erosion and severe structural damage, significantly reducing the service life.
The role and characteristics of transportation roads determine the importance and uniqueness of highway maintenance and management. Ensuring effective maintenance of highways is a long-term and arduous task. Currently, there are numerous methods for repairing concrete road cracks. Next, we will focus on one of the main materials for repairing cracks in cement concrete roads: sealant adhesive.
Sealant for Joint Filling
[Sealant Composition] The sealant is a one-component, new type of oil-based cold-applied sealant material. It is a flexible material with special resistance to displacement changes and waterproofing properties. It absorbs moisture from the air to cure, has strong weather resistance, and will not ooze even after curing at high temperatures, nor will it crack at temperatures below -20°C. It can be applied between 50°C and -25°C. The material will not peel off before or after rain and maintains elasticity. The color of the sealant is typically gray, suitable for sealing cracks and expansion joints in concrete pavements.
[Seam Filler Properties] Single-component, ready to use upon opening, self-leveling in liquid form at room temperature, no additional operation required, color is usually gray.
[Application Range] Suitable for bonding and sealing of cracks in asphalt concrete pavements (more cost-effective to use asphalt crack sealant), and surface cracks in cement concrete pavements. It is applicable to expansion joints, settlement joints, saw cuts, and construction joints of newly paved cement pavements in squares, airport runways, roofs, and basements.
[Key Features] Simple joint sealing process, ready to use upon opening (with a dedicated adhesive nozzle), fast curing, immediate traffic opening, high bonding strength and good flexibility after curing. Suitable for construction from -20°C to 80°C, excellent resistance to acids and alkalis, waterproof, oilproof, and dustproof, as well as resistance to humidity and aging. Features good tensile, pressure resistance, and bonding strength.
[Usage Instructions]
1. Preparing: Remove debris from cracks wider than 3mm with a metal hook before filling. The crack and both sides should be clean and free of dirt, fragments, and weeds.
2. Joint Widening: For cracks less than 3mm wide, use a joint widening machine. The widened joint width is generally 4 to 6mm, and the depth is 6 to 10mm.
3. Dust Removal: Utilizing a dust removal machine to ensure thorough cleaning of floating dust, followed by using an elastic steel brush to scrape out loose concrete debris left in the gaps after expansion.
4. Filling: For wider and deeper cracks, fill the cleaned crack with gravel or elastic foam strips with particle sizes larger than the width of the crack before injecting the adhesive, leaving a space of 0.5-1cm above for the adhesive.
5. Gluing: For cracks less than 3mm wide, the crack must be widened first using a crack widening machine before the glue is injected. The ideal width and depth after widening should be 6-8mm. (The reason for widening is that due to the narrow width of the crack, the inherent surface tension of the filling glue cannot achieve self-leveling of the gel, thereby preventing smooth injection into the crack.) After widening, each kilogram of filling glue can fill 20-30 meters of crack. For cracks wider than 3mm.
6. Concrete road repair joint sealing: The width of the cut joint is generally 1 cm and the depth is 7 cm. Sand or elastic foam strips can be used to fill the crack during sealing. Leave a space of 0.5 cm above for the sealant. Each kilogram of joint sealant can seal a joint for 15 meters.
7. Open Traffic: The surface drying time of the sealant is less than 1 hour at temperatures above 15°C; the drying time is relatively extended at temperatures below 15°C. For cracks less than 1 cm wide, traffic can be reopened directly after injection.
