Application of Superworkable Concrete in the Construction of 70-Story Building in Japan
M. Hayakawa, Y. Matsuoka, and K. Yokota
Appears on pages(s):
admixtures; columns (supports); formwork (construction); superplasticizer; viscosity; Construction
A superworkable concrete, which has excellent deformability and resistance to segregation and can be placed in heavily reinforced formwork without vibrators, was developed and employed in the construction of a 70-story building. The height of the building is 296 m, and the height of the superworkable concrete in the tubular columns is about 40 m. Some of the columns have two diaphragms with opening ratio of seven percent at each joint of column and beams. Before actual construction, the placing of the concrete into three model columns was conducted. From the tests, it was confirmed that the superworkable concrete had excellent filling ability and left no voids under the diaphragms. A 6-m high removable column was set on top of the 40-m high column of the building to check the quality of filled concrete. The superworkable concrete was placed successfully into 66 columns of the tallest building in Japan.