About This Project

On August 1st, 2010 Bridge Preservation’s seamless elastomeric waterproofing membrane was installed on Rhode Island DOT’s Pontiac Avenue Bridge #201 in Cranston, Rhode Island.

The project began with abrasive sandblasting to remove residual surface contaminates such as asphalt surfacing remnants, dirt, and grease. Surface preparation is critical because it provides the mechanism by which the seamless elastomeric waterproofing membrane will adhere to the deck and ensures a long service life.

Immediately following surface preparation ambient conditions were recorded by a Bridge Preservation inspector. Temperature and concrete moisture content were measured. In order to ensure that the installation is successful, the inspector is looking for the ambient temperature to be 5ºF above dew point and rising prior to the application of the primer and waterproof membrane. Moisture content needs to be 5% or lower to ensure proper adhesion. Primer was then installed and pull tests were conducted using an Elcometer. The inspector was looking for minimum tensile pull-off values of at least 150 PSI, but cohesive failure within the concrete is desirable.

The primer was allowed to completely cure, which took approximately 30 minutes. After the primer was cured, Bridge Deck Membrane seamless elastomeric waterproofing was applied at a thickness of 80 mils.