PURPOSE: To provide a static breaking agent which makes it possible to break laid concrete in a desired part upon solidification of the concrete, by filling particles or powder of a hydration swelling substance or its blend with sand or gravel in a tube so that it may absorb water through an opening of the tube and swell.
CONSTITUTION: The breaking agent is prepared by filling particles or powder of a hydration swelling substance or its blend with sand and/or gravel in a tube so that it may absorb water poured through an opening of the tube and swell. The breaking agent in the tube is buried in laid concrete, with the opening of the tube coming up to the surface or filled in a hole made in rock or concrete and water is poured through the opening to cause swelling of the breaking agent. The hydration swelling substances are, e.g., quick lime, burned dolomite and ettringite.
NAKAZAWA SOZO
SHIROI TAKESHI
JPS59206556A | 1984-11-22 | |||
JPS5945379A | 1984-03-14 |