Abstract
The geological survey of surface and boring survey was carried out to build a bridge on the fault sheared zone, and was estimated as a result of investigation. A support layer could be confirmed by the boring survey, and it was judged that bridge construction was possible. This fault sheared zone belongs to the Median Tectonic Line Active Fault system which is one of the most highly active fault in Japan. But, the main active fault locates 0.5 to lkm north of the planning point. And investigated fault sheared zone has not been so active since the late Pleistocene. Therefore, I proposed it when it could cope with it by holding earthquake-proof design based on active fault presumed in the neighborhood of the investigation area.
