Rev. 7-17-97
HIGH RANGE WATER REDUCERS
IN PRECAST PRESTRESSED CONCRETE STRUCTURAL MEMBERS
707-B-013
The Standard Specfications are revised as
follows:
SECTION 707, BEGIN LINE 121, DELETE
AND INSERT AS FOLLOWS:
(c) Concrete. Concrete shall be air entrained
and in accordance with the applicable provisions requirements of
702.05. Water-reducing admixtures, or water-reducing and retarding
admixtures, or high range water reducing and retarding admixture systems may be
used. Admixture and admixture systems shall be in accordance with 912.03. The
use of either a type A or a type D chemical admixture shall be in accordance with 702.05
as specified for class C concrete. If a high range water reducing admixture system is to
be used in portland cement concrete, the procedures for batching shall be consistent. The
concrete shall be mixed until a uniform consistency is achieved.
Admixtures shall not contain chlorides which have been added
SECTION 707, LINE 128, INSERT AS FOLLOWS:
will not apply. Slump shall be no less than 50 mm (2 in.) nor more than 125 mm (5 in.). Concrete
with high range water reducing or a high range water reducing retarding admixture system
shall be in accordance with the requirements as follows:
The slump shall
be a minimum of 75 mm (3 in.) and a maximum of 150 mm (6 in.).
The
amount of time from mixing to final placement and consolidation shall be a maximum of 30
minutes.
The
concrete mixture shall not be retempered with additional amounts of high range water
reducing or high range water reducing and retarding admixture after the initial mixing has
been completed.
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