Internally sealed concrete at Cow Creek, Oklahoma (FHWA-OK-81-1)

Abstract

This report discusses Oklahoma's second experimental internally sealed concrete bridge deck. It differed from the first one in that it contained wax beads only in the top two inches as opposed to full depth, and it covered the entire deck instead of just one span. The objective of this study was to gain experience in placing and heating a wax impregnated concrete bridge deck on a full-scale basis. Work was performed on an existing Interstate bridge that needed widening and redecking. The bridge's maintenance history is included. The project design and construction phases are described in detail. The deck was placed with two pours instead of a monolithic pour as originally planned. A petrographic classification was made of the aggregates. The mix design detailing the conversion from conventional bridge deck concrete to wax bead concrete is explained. A trial mix was made prior to pouring the wax bead overlay to insure good bead distribution. The heat blankets and heat treating method used to internally seal the deck are described. Tests to determine the effectiveness of the wax seal are discussed. These included: (l) A before and after heating crack survey, (2) 24 hour absorption, (3) Dye penetration, (4) skid resistance, (5) half-cell potential, (6) compressive and flexural strength, and (7) a chloride analysis. All of the tests showed good results. This method deserves serious consideration in the bridge design process.