Sealants for bridge foundation increase reliability and safety
One of the most critical parts of a bridge is the foundation: it must be safe and reliable as the weight of the entire bridge lays on it together with the traffic on the bridge. To guarantee bridge safety and construction reliability, sealants for bridge foundation are used. The sealants fill and seal joints in the foundation making them watertight.
Sealants for bridge foundation are used especially on footings such as pedestal footing, pile footing and spread footing. Here the sealant can be applied to the pile caps in order to seal the joints between the cap and columns, piles or walls depending on the construction design.
Desired properties of sealants for bridge footings
As bridge footing must be absolutely reliable, sealants are used to prevent water from seeping into the structures. Most of the times the footings are made of concrete meaning that the sealants for bridge foundation must be designed for the specific material. Note that if joints between asphalt and concrete require sealing, a special product is needed.
The desired properties of sealants for bridge footings include the following.
- Watertight: most importantly, the sealant for bridge foundation must be water tight. Some products can even be applied underwater.
- Flexibility: depending on the environment and climate conditions, the footings may be subject to movement caused by temperature fluctuation, heavy traffic on the bridge or soil type. The sealant must not crack but be flexible enough to allow the movement.
- Chemical resistant: the environment of the footing defines the need for chemical resistance of the sealant. Common chemicals that the sealants may be subject to include fuels, road salt and salt water.
- Resistant to microorganism: the sealant should also be resistant to microorganisms present in the specific environment such as algae and moss.
Which properties are the most important for your bridge foundation and which sealant has those? Send us a message to find out!
Determining the best sealant for bridge foundations
The choice of the sealant for bridge foundation should be based on the bridge and foundation type, requirements of the soil and climate as well as the preferences of the applicators.
Sealants for bridge footings include MS polymers, polymerized and cementitious systems, silicone based solutions as well as polysulfide sealants. Similar systems are also applied to other expansion joints in bridge constructions. To determine the best type of sealants for bridge foundation some factors must be considered.
- Debris accumulation: some sealants let more debris and dirt accumulate than others. This is a factor to consider especially in environments where the chance of pollution is above average.
- Joint width: the joint width affects the choice of sealant as some are designed for narrow seams and the others perform better in wider joints.
- Movement capability: the sealants vary by flexibility. When great movement of the concrete (or asphalt) is expected, a flexible sealant with movement capability between 50% and 100% is recommended.
- Curing time: the curing time of the sealant is important regarding efficiency. However, the fastest curing solution is not always the most reliable.
- Pretreatment: also related to efficiency, the pretreatment required to guarantee good adhesion is important. Some sealants can be applied directly to clean concrete whereas others require a primer.
Guarantee bridge reliability with the best sealant for footings
The bridge footing must be appropriately sealed in order to guarantee a foundation which is capable of carrying the weight of the bridge and the traffic on the bridge. There are different types of sealants with different properties, the best one is chosen based on several factors such as the requirements of the environment, type of the bridge and the foundation design. Discover which sealant offers the most reliability to your bridge foundation – get in touch with us!