CONCRETE FOR PLACING JOINT AND METHOD FOR PLACING JOINT USING THE CONCRETE FOR PLACING JOINT

摘要

PROBLEM TO BE SOLVED: To improve the adhesiveness, strength, durability and execution characteristic of an existing concrete structure surface by incorporating an AE water- reducing agent or high-performance AE water-reducing agent into the concrete and specifying the slump, water cement ratio and fine aggregate rate. ;SOLUTION: The concrete for placing joint is obtd. by mixing low heat Portland cement, water, the AE water-reducing agent or the high-performance AE water-reducing agent and the fine aggregate and if necessary, an org. shrinkage reducing agent in such a manner that the slump attains 2 to 8 cm, the water cement ratio 35 5o 45% and the fine aggregate rate 36 to 42%. The crack and damage portions of the surface layer of an existing concrete pavement 1 are cut by a water jet treatment, by which macroruggedness 4 is formed on the surface of the concrete pavement 1. Next, the surface of the ruggedness 4 is subjected to a shot blast treatment to form microruggedness 6 and thereafter the concrete for jointing of successive pours is placed and is leveled off by a concrete finisher or the like. The placing joint is then executed by applying vibration for 10 to 60 seconds at a number of vibration of 2600 to 3700 vpm.;COPYRIGHT: (C)1999,JPO