Mechanism and Countermeasures for Waterproof Layer on Blistering due to Concrete Slab Surface Condition

This chapter presents some results of a study on effects of concrete slab surface condition on waterproof layer blistering, as well as some countermeasures. In the study, dozens of concrete slab specimens were made under different conditions to produce different concrete surface conditions, then those surface denseness was evaluated via air permeability testing. The blistering resistance of the waterproof layer was tested to observe the effects of concrete surface denseness and water content on the occurrence of blistering. Furthermore, the suppression effect of blistering when a highly permeable resin primer was applied to the waterproof layer was verified. It was found that a higher air permeability coefficient, measured with dry concrete slabs, increased the risk of blistering. The results show that high-permeation resin primers suppress blistering.