METHOD FOR PLACING CONCRETE WHILE DISPERSING CRACK CAUSED BY TEMPERATURE STRESS

摘要

PROBLEM TO BE SOLVED: To provide a new simple and effective method for bringing about the rendering harmless of a crack caused by temperature stress in concrete in hardening.;SOLUTION: In the method for placing the concrete while dispersing the cracks caused by the temperature stress, after a form is installed in the placing construction of a concrete structure, a crack dispersion-type HPFRCC (High Performance Fiber Reinforced Cement Composite) presenting a tensile distortion of 1% or more at a material age of 28 days is sprayed to a thickness of 10-150 mm on the placing-side surface of the form; fresh concrete is placed to come into contact with the surface of the HPFRCC in hardening by the time when the compressive strength of the HPFRCC reaches half the strength at the material age of 28 days; and the HPFRCC and the concrete are integrated together. For example, the HPFRCC contains 1-3 vol.% of PVA staples with a fiber diameter of 0.05 mm or less and a fiber length of 5-20 mm.;COPYRIGHT: (C)2010,JPO&INPIT