State-of-Art-Report on Characteristics of SHIRASU Concrete and
its Practical Use
By K. Takewaka
Concrete Journal, Vol.42, No.3, Mar. 2004
- Synopsis
- Shirasu concrete is defined as a concrete using Shirasu as fine aggregate. Shirasu is a kind of pyroclastic flow deposits and the huge volume of it accumulate in the southern part of Kyushu Island, Japan. Its particles can effectively react as Pozzolan in concrete to produce durable one, although Shirasu is classified into the nonstandard aggregate because of its lower specific gravity, higher water absorption ratio and large content of the fine powder. In this report, characteristics of Shirasu concrete and its mixture design method are briefly mentioned and they are followed by an explanation of newly developed self-compacted concrete with Shirasu. Furthermore, the author introduces some activities for practical use of Shirasu concrete in Kagoshima prefecture, including the first trial of a real construction of the concrete in the foundation of bridge structure constructed in hot spring environment.
- Keywords:
- Unused natural resource, Pyroclastic flow deposit, Shirasu concrete, Pozzolan, Materials for mixture design, Durability
