A Case Study of Design Change in the Press-in Method

抄録

This paper describes a renovation work of the old Kaishin Bridge over a class-I Nishiyoke River in Kitanoda, Higashi-ku, Sakai, Osaka. The project was ordered by the Civil Engineering Office of Tondabayashi, Osaka. The site was near the station with a heavy traffic of vehicles and pedestrians, and the work had to be done adjacent to residential houses on both the sides of the river. Since steel sheet piles were used as a temporary earth retaining wall to remove an old weir and build a new abutment, the Press-in method with water jetting was selected at the design stage. However, the soil boring log showed the maximum SPT N-value is over 50, indicating that it might be impossible to press-in piles. Furthermore, there were possibilities that the sludge might flow into the river and the surrounding ground would be affected. Hence, the Hard Ground Press-in Method was selected instead, after the design change. The whole construction process including the pull out works of steel sheet piles was completed by us, the prime contractor, Fujii Co., Ltd.