補修・補強（材料）(2)

[V-123] Investigation of waterproofing primers for bridge decks overlaid with UHPFRC

〇Tohru Makita¹, Yuji Watanabe², Yoshiki Mitsuyama², Toshinari Mukai², Kato Kenta¹ (1.Central Nippon Expressway Company Limited , 2.Kajima Corporation)

Keywords:UHPFRC, Road bridge decks, Renewal, Construction joint, Waterproofing primer, gap filling

When UHPFRC is overlaid on top of bridge decks, a small gap is usually made at construction joints in the UHPFRC layer due to relatively large shrinkage deformation of UHPFRC. If the gap is not filled with some materials, water possibly enters into the gap and might cause debonding of the UHPFRC layer where wheel loads are acting on bridge decks. As the material to fill the gap, waterproofing primer is considered to be appropriate because waterproofing membrane will be applied on top of the UHPFRC layer based on the concept of multi-layer protection. Properties of waterproofing primers available in the market are investigated and the result of the investigation is presented in this paper.