
Researcher Profile
Ayaka Ishii
IRF: What was the key rationale behind your research?
Ayaka: The embedded expansion joints are used for short span of prestressed concrete brides. However, these embedded expansion joints using the guss asphalt have a durability problem because of damage occurring over a few years after repair. We made test structures of embedded expansion joint using conventional material and new material similar to an actual bridge. We confirmed how these embedded joints damaged as test load of wheel road running test increased.
IRF: What are the main findings of your research and what can the industry learn from them?
Ayaka: The wheel road running tests show that the damage of the new embedded expansion joints was lesser then that of the conventional embedded expansion joints. The new embedded expansion joint, which was fabricated using high-flexibility stone mastic asphalt, has high durability when used in the complete base course in maintenance work.
IRF: As a researcher, what is the chief value of presenting your work at an IRF conference?
Ayaka: A lot of embedded expansion joints are used for prestressed all over the world bridges, clacks on the surface is major problem in there. It is useful to introduce the durable new embedded expansion joint at an IRF conference that a lot of top Technical & Scientific Experts participate in. We expect that these techniques are widely used.
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