BRIDGE DECK COATINGS
Bridge Deck Waterproofing is considered globally as a vital and necessary operation to enhance the durability and longevity of the life of bridge.
The ETAG 033 guideline for European Organisation for Technical Approval (EOTA) of Liquid Applied Bridge Deck Waterproofing emphasises the Assessment, Evaluation and Conformity fitness of products to be used for Bridge Deck Coatings.
Some of the properties of a products used for Bridge Deck Coatings that should not be compromised, as they directly influence the performance of the concrete structure and its durability.
Those properties are;
- The high BOND STRENGTH between the waterproofing and the overlay, so that it is not de-attached due to traffic stress.
- High TENSILE STRENGTH and ELONGATION to resist forces and movements associated with cracks of base concrete slab and the overlay.
- Resistance to CHLORIDE ION INGRESS into the concrete by full bonding to the substrate and avoid lateral movement between substrate & the waterproofing layer.
- Should have THERMAL RESISTANCE > 200° C to take up the application of hot applied surfacing over lay directly over the coating without a protection layer.
- RESIST SHEAR FORCE acting on waterproofing layer due to traffic movement and differential thermal movement.
- Should be seamless layer with WATER ABSORPTION LESS THAN 1% to protect the bridge deck against any percolation.
- SERVICE LIFE of the proposed waterproofing should not get affected due to deleterious action when in contact with Water, Oil, Petrol, Diesel, Salts etc.
- Excellent adhesion on almost any surface.
- Durability certificate for intended service life above 25 years.
- Have resistance to take thermal shocks of hot asphalt over lay above 220° c
- Elongation more than 250% to bridge cracks due to thermal stress.
- Resistance to very cold temperatures that it remains elastic even down to -40°c
- With excellent abrasion resistance of less than 30 mg loss.
- Thixotropic to apply it on slope of inclined surfaces and also fluid enough to seal pores.
- Very good chemical resistance & resistance to hydrolysis
- Non-toxic after full cure