METHOD OF PREVENTING CRACK AND CEMENT HARDENED BODY

• Main Authors: KIDA TSUTOMU, TANAKA KUNIYUKI, HIRAI YOSHIHIKO
• Format: Patent
• Language: English
• Published: 05.04.2007
• Subjects: ARTIFICIAL STONE; CEMENTS; CERAMICS; CHEMISTRY; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDINGMATERIALS; CONCRETE; LIME, MAGNESIA; METALLURGY; REFRACTORIES; SLAG; TREATMENT OF NATURAL STONE

PROBLEM TO BE SOLVED: To provide a method of preventing crack on expansive concrete by which the crack occurring in the initial time of material age to such an extent to the day after the next since the cement concrete is surface-finished can be prevented and which is used in the field of civil engineering or building, and to provide a cement hardened body therefor. SOLUTION: In the method for preventing the occurrence of the cracks on the surface of the cement concrete, when performing surface-finishing of the cement concrete placed but before hardened, a dry shrinkage reducing agent is sprayed. The cement concrete is placed and rough leveling work, screeding work and final-finishing work are carried out thereon. In the surface-finishing the placed cement concrete before hardened, the dry shrinkage reducing agent is sprayed to prevent the occurrence of the crack on the surface of the cement concrete before the screeding work and/or the final-finishing work. The dry shrinkage reducing agent is sprayed by 10-300 g/m2expressed in terms of an active ingredient before the screeding work and/or sprayed by 5-150 g/m2expressed in terms of an active ingredient before the final-finishing work. The cement hardened body is produced by the method of preventing the crack. COPYRIGHT: (C)2007,JPO&INPIT