Evaluation of concrete deck and crack sealers

Abstract

The primary objective of this study was to assess the effectiveness and relative performance of commercially available concrete bridge deck and crack sealants. A total of thirteen deck sealants and ten crack sealants were selected for study under laboratory conditions that simulated the exposure to deicing salts and freeze-thaw cycles encountered in practice. Based on the results of this study, sealants that offered the best performance were assigned to Performance Group Category I, those that offered a moderate level of protection were assigned to Performance Group Category II, and those that offered the least amount of protection were assigned to Performance Group Category III. Of the thirteen deck sealants studied, two products [Sonneborn Penetrating Sealer 40 Volatile Organic Compound (VOC) and Hydrozo Silane 40 VOC] surpassed the rest and thus they were assigned to Performance Category I. Six other sealants offered moderate protection and were assigned to Performance Category II. The remaining five sealants offered the least protection and were assigned to Performance Category III. The performance of crack sealants depended on the crack width considered. Of the ten sealants tested in this study, Sikadur 55 SLV showed excellent performance in hairline, narrow and medium cracks and was assigned to Performance Group Category I. Dural 335 also performed very well in the crack size recommended by the manufacturer, i.e., hairline cracks and was also assigned to Performance Group Category I. Three other sealants performed well in hairline, narrow, and medium cracks when not exposed to freeze-thaw cycles, but were adversely affected by freeze-thaw cycles and were assigned to Performance Group Category II. The remaining crack sealants showed low bond strengths, large reductions in strength when exposed to freeze-thaw cycles and were assigned to Performance Group Category III. Only two products were tested in specimens with wide crack widths. Their performance was poor and thus they were assigned to Performance Group Category III.