3.1.5
Transporting and Conveying Equipment
The transporting and conveying equipment shall conform to the following
requirements.
a. The concrete mixtures (RCC, bedding mortar, concrete, and any other
concrete that will interface with the RCC) shall be conveyed from the
plant mixer(s) to placement as rapidly and as continuously as practical
by methods which limit segregation, contamination, and surface drying.
b. The RCC shall be conveyed from the mixing plant to the structure by
means of main-line conveyor, end-dump truck, front-end loader, or a
combination thereof.
c. Conventional concrete may be transported by ready-mix truck,
conveyor, or agitator truck, or properly designed nonagitating truck.
d. Indicating and signaling devices shall be provided for the control
and identification of types or classes of concrete as they are mixed
and discharged for transfer to the placement site.
e. Each type or class of concrete shall be visually identified by
placing a colored tag or other marker as it leaves the mixing plant so
that the concrete may be positively identified and placed in the
structure in the desired position.
3.1.5.1
Trucks
Truck mixers or agitators used for transporting central-mixed conventional
concrete shall conform to the applicable requirements of ASTM C 94/C 94M.
Truck mixers shall not be used to transport concrete with larger than 37.5
mm 1-1/2-inch nominal maximum size aggregate (NMSA) or 50 mm 2 inch slump,
or less. Nonagitating trucks may be used for transporting conventional
central-mixed concrete over a smooth road when the hauling time is less
than 15 minutes and the slump is less than 75 mm 3 inches. Bodies of
nonagitating trucks shall be smooth, water-tight, metal containers
specifically designed to transport concrete, shaped with rounded corners to
minimize segregation.
3.1.5.2
Belt Conveyors
Belt conveyors shall be designed and operated to assure a uniform flow of
concrete from mixer or delivery truck to final place of deposit without
segregation of ingredients or loss of mortar and shall be provided with
positive means for preventing segregation of the concrete or loss of mortar
at transfer points and the point of placing. The NMSA required in mixture
proportions furnished by the Government will not be changed to accommodate
the belt width.
3.1.6
Spreading and Remixing Equipment
The spreading and remixing equipment shall conform to the following
requirements:
a. The primary spreading procedure shall be accomplished by dozer.
Graders or other equipment not specified may be used to facilitate the
RCC spreading process only when approved.
b.
For open, unrestricted areas, the dozer shall be a minimum size and
SECTION 03701
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