Title:
Pullout Tests on Straight Deformed Bars Embedded in Super Plasticized Concrete
Author(s):
Peggy M. Carrasquillo
Publication:
Materials Journal
Volume:
85
Issue:
2
Appears on pages(s):
90-94
Keywords:
air entrainment; bleeding (concrete); compressive strength; bond (concrete to reinforcement); melamine resins; naphthalene; plasticizers; pullout tests; reinforcing steels; water-reducing agents; splitting tensile strength; temperature; Materials Research
DOI:
10.14359/2294
Date:
3/1/1988
Abstract:
The bond performance of reinforcing steel embedded in superplasticized normal weight concrete was studied. Pullout tests were conducted on straight deformed bars having an embedded length of either 6 or 8 in. (152 or 203 mm). Variables studied were the slump of the concrete before and after the addition of the superplasticizer, the type of superplasticizer used, and the depth of fresh concrete cast under the pullout bars. To determine which properties of the concrete were affected by the addition of the superplasticizer and how these, in turn, affected the bond behavior of the reinforcing bars embedded in that concrete, several properties of the fresh and hardened concrete were tested. These included concrete slump, air content, temperature, bleed, compressive strength, and splitting tensile strength. The test results indicated that the effects of a sulfonated naphthalene formaldehyde condensate on fresh and hardened concrete properties were quite different from those of a sulfonated melamine formaldehyde condensate. However, in no case was the pullout capacity of straight deformed bars embedded in superplasticized concrete significantly less than that of bars embedded in the concrete containing no superplasticizer.