BEJS Bridge Joints

Composition

• BEJS is produced by coating an impregnated cellular foam with AASHTO-approved, Pecora 301 highway-grade silicone.
• The expanding foam is cellular polyurethane foam impregnated with a water-based acrylic containing a high performance micro-cellular additive.
• The silicone external facing is factory applied to the foam at a width greater than maximum joint extension and is cured before final compression. 
• Silicone application and curing takes place in a factory-controlled environment. In contrast to field applied liquid sealant and backer rod installations, no movement takes place during curing that can cause deformation or stresses in the material.
• When compressed, a bellows is created in the coating. As joint movement occurs the bellows simply folds and unfolds free of tension on the bond line, and virtually free of tensile stresses in the silicone material. Sizes under 25mm (1") have a single-curve convex bellows; sizes from 25mm (1") through 100mm (4") have a dual-curve convex bellows. 
• The foam provides a resilient backing to the silicone coating, making the system capable of resisting reasonable transient point loads. 
• BEJS SYSTEM is supplied in 2mtr (6.56') shrink-wrapped lengths (sticks). It is precompressed to less than the joint size for easy insertion. After removal from the shrink-wrap and hard board restraining packaging, it expands gradually.

Limitations:

• Capable of movements of +/-50% (100% total) of nominal material size.
• Substrates must be parallel, plumb and capable of resisting approx. 2.5 psi backpressure from the foam. 
• Standard sizes from 12mm (1/2") to 100mm (4"). Other sizes available subject to review of application: consult Allco.
• Fuel Resistance: Silicone sealant is not degraded by contact with fuel. Some swelling of the material will normally occur, but it will return to its original shape upon evaporation of the fuel.