Investigation of factors affecting bond strength of thin epoxy overlay pavements

초록

This study investigated the factors influencing the bond strength between existing pavement and thin epoxy overlay via laboratory and field tests. Laboratory tests revealed that the highest bond strength occurred at a general temperature and relative humidity of 25 degrees C and 60%, respectively. The concrete surface profile (CSP) of the specimen was found to have no impact on the bond strength between the latex-modified concrete (LMC) and epoxy binder under favorable conditions. Field testing of well-maintained concrete pavements indicated that neither the existing pavement's pre-treatment process nor its resulting CSP affected the bond strength. However, the bond strength decreased with environmental and vehicle loadings six months after the overlay. A second field test conducted on a deteriorated bridge deck with an LMC pavement revealed that most of the damage occurred at a shallow depth in the existing pavement, demonstrating low bond strength just two days after construction owing to inadequate removal of the deteriorated section. The initially low bond strength increased over time as the epoxy binder permeated the deteriorated area and hardened at greater depths, thus making it necessary to thoroughly remove all deteriorated sections of the existing pavement before constructing a thin epoxy overlay.

키워드