Komatsu Corporation

Taiheiyo Cement Corporation

Minoru Yoshimoto

Yasuhide Higo

Eichi Manabe

Takeshi Hamada

Kazuya Kuriyama

Wataru Kataoka

Disclosed is a counterweight which is filled with a heavy-weight concrete containing, instead of currently used iron ores, a heavy-weight aggregate that scarcely causes the material segregation from cement paste and which can be produced at a low cost and is effectively enhanced in the filling factor of heavy-weight concrete into a case. A counterweightcomprises a caseand heavy-weight concrete filled therein, wherein the heavy-weight concrete contains a heavy-weight fine aggregate containing 20 mass % or more of aggregate particles having particle diameters of less than 0.15 mm and 20 mass % or more of aggregate particles having particle diameters of 2.5 mm to less than 5 mm.

Counterweight

It is aimed at providing a heavy concrete, which does not require addition of a thickener such as methyl cellulose, which is less in segregation between a heavy aggregate and a cement paste, and which is high in flowability and excellent in construction ability. The present invention provides a heavy concrete comprising, at least, a cement, a heavy aggregate, and water, mixed with one another, characterized in that the heavy fine aggregate includes hot scarves brought about in a scarfing process of a steel slab surface. The present invention further provides the above-described heavy concrete characterized in that the heavy fine aggregate includes fine aggregate particles passing through a sieve having a nominal size of 0.15 mm, in an amount of 10% to 20% in mass percentage, and the heavy fine aggregate includes spherical particles each having a distortion irregularity of 3.3 or less as defined below, in an amount of 20% or more in the whole of particles having diameters between 50 &#x3bc;m inclusive and 5 mm inclusive in the heavy fine aggregate:[Distortion irregularity]=[Length of circumferential outline of particle]/[Diameter of true circle having the same area as the area of the particle providing the outline].

Heavy concrete

Growing community of inventors

Sakura, Japan

Minoru Yoshimoto