Bridge foundation sealants 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, bridge foundation sealants are used. The sealants fill and seal joints in the foundation making them watertight.
Bridge foundation sealants are used especially on bridge 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 footing systems
As bridge footing must be absolutely reliable, special sealants are used to prevent water from seeping into the structures. In most of the cases the bridge footings are made of concrete meaning that the bridge foundation sealants must be designed for the specific material. Note that if joints between asphalt and concrete require sealing, a special product is needed. Get more information on these systems by contacting us.
The desired properties of sealants for bridge footing systems include the following.
- Watertight: most importantly, the bridge footing sealant 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 for bridge foundation must not crack, but be flexible enough to allow the movement.
- Resistant to microorganism: the sealant should also be resistant to microorganisms present in the specific environment such as algae and moss.
- Chemical resistant: the environment of the footing defines the need for chemical resistance of the bridge sealant. Common chemicals that the sealants may be subject to include fuels, road salt and salt water.
Determining the best sealant for bridge foundations
The choice of the sealant for foundation should be based on the bridge, footing and foundation type, requirements of the soil and climate as well as the preferences of the applicators.
Bridge footing sealants include industrial systems such as 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.
- Movement capability: the sealants vary by flexibility. When great movement of the concrete (or asphalt) is expected, a flexible foundation 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 bridge foundation sealants can be applied directly to clean concrete whereas others require a primer.
- 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.
Guarantee bridge reliability with the best bridge foundation sealant
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 bridge foundation 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 footing design. Discover which sealant that offers the most reliability to your foundation – get in touch with us!