Title: Engineering Properties of Superplasticized Concretes
Author(s): K. Kishitani, H. Kasami, M. lizuka,
T. Ikeda, Y. Kazama, and K. Hattori
Publication: Symposium Paper
Appears on pages(s): 233-252
Keywords: admixtures; compressive strength; drying shrinkage;
field tests; lightweight aggregate concretes; models; naphthalene
compounds; plasticizers; pumped concrete; ready-mixed concrete;
reinforced concrete; slump tests; vibration; workability.
A series of laboratory and field studies were conducted to determine the engineering properties of concretes containing a sulphonated naphthalene formaldehyde condensate superplasticizer (MIGHTY). In laboratory studies, conventional and superplasticized concretes with slumps from 12 to 21 cm were placed into moulds for full-size, single-frame models of reinforced concrete structures for measurements of form pressures and response to internal vibration as well as tests on the strengths and drying shrinkage in finished structures. Superplasticized concrete indicated greater response to vibration than and equal form pressures to conventional low-slump concrete. Higher core strengths were obtained with superplasticized concrete than with conventional concrete, while no change was observed in drying shrinkage with addition of the admixture. Further studies were conducted on ordinary and lightweight aggregate concretes in the construction of a ten-storey, reinforced concrete structure. Higher fluidity was observed in super-plasticized concrete, while the same trends as in the laboratory were observed regarding form pressure and core strengths. The test results on pumpability indicated that superplasticized lightweight aggregate concrete can be pumped at a lower pressure to a height of fifty meters without adversely affecting concrete properties.