placement. Following this initial preparation, the cold-joint surface
shall be kept continuously moist until application of the bedding mortar.
Whenever a cold joint at any edge or end of any lift occurs, it shall be
located at least 10 m 30 feet from the location of other cold joints that
may have previously occurred in the same direction along previous lifts.
3.3.7.3
Vertical Joints
Joints for sloping, near-vertical or vertical RCC surfaces are considered
to be vertical joints. A vertical joint most often will occur when an RCC
placement is terminated before the entire RCC placement for that lift has
been completed. When it does become apparent that placement of RCC will be
terminated prior to completion of a lift, the RCC spreading procedure at
the leading zone of the placement shall be adjusted to provide a gradual
tapered slope to complete that lift. The taper shall be no steeper than 25
horizontal on 1 vertical. Where the tapered slope meets the underlying
hardened lift surface, care shall be taken to prevent or remove any
segregated or uncompacted material. The tapered surface shall be compacted
in accordance with paragraph COMPACTION/CONSOLIDATION. Prior to resumption
of RCC placements, the tapered surface shall be prepared in accordance with
paragraph SURFACE PREPARATION.
3.3.8
Downstream Face
**************************************************************************
NOTE: See the concrete materials DM to select one
of the two optional systems for the downstream face.
**************************************************************************
3.3.8.1
[Using Sacrificial Concrete
The downstream sloped face of the dam and the exposed slopes of the
stilling basin training walls shall be constructed using sacrificial RCC on
[[_____] vertical to [_____] horizontal slope] [1 vertical to 0.85
horizontal slope]. The slope shall be constructed to the tolerances
specified. Each RCC lift shall be overbuilt at least 300 mm 12 inches, and
it shall subsequently be trimmed to the surface smoothness tolerance.
Trimming shall be performed before the RCC is more than 48 hours old. The
process shall be demonstrated during the test section. Trimming shall be
done in such a manner to prevent damage to the surface and interior RCC.]
3.3.8.2
[Using Conventional Concrete
The downstream face shall be constructed of conventional concrete in
accordance with paragraph VERTICAL FACINGS FOR RCC CONSTRUCTION.]
3.4
CURING AND PROTECTION
3.4.1
Curing
The surface of every RCC lift shall be kept continuously moist, commencing
immediately after compaction, by use of water trucks equipped with fog
sprayers for 14 days or until the surface is covered with the next lift.
The sloping downstream surface of the Dam, [and the [_____]] if constructed
of uncompacted sacrificial RCC, need not be cured. Curing and protection
for all conventional concrete used in the construction of the vertical
faces and any horizontal RCC surfaces that will not receive a subsequent
concrete covering shall be moist cured. Conventional concrete made with
Type II portland cement, or any type of portland cement with pozzolan, and
SECTION 03701
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