(5) The recorder chart or tape shall become the property of the
Government.
(6) The recorder shall be placed in a position convenient for
observation by the concrete plant operator and the Government
inspector.
(7) The recorded weights or volumes when compared to the weights
or volumes actually batched shall be accurate within 2 percent.
i. Batch Counters - The plant shall include devices for automatically
counting the total number of batches of all concrete batched and the
number of batches of each preset mixture.
j. Rescreening Plant - A rescreening plant shall be located, arranged,
and operated in a manner that all coarse aggregate will be routed
through the plant and that its operation will ensure delivery to the
mixers of graded coarse aggregate free from excessive variation and
conforming to the size groups and grading of paragraph AGGREGATES and
with moisture content conforming to the provisions of paragraph
MOISTURE CONTENT. Coarse aggregate may be rescreened and delivered to
the batch plant bins one size group at a time or two or more adjacent
size groups at a time. Simultaneous rescreening of nonadjacent size
groups is not permitted. All material passing the bottom screen of the
smallest size of coarse aggregate being screened shall be wasted.
k. Washing Plant - All coarse aggregates shall be washed immediately
prior to entering the rescreening plant. The rewashing plant shall
contain adequate water nozzles and vibrating screens to remove foreign
materials and coatings from aggregate particles. Water used for
washing shall meet the requirements of paragraph WATER.
l. Trial Operation - Not less than 7 days prior to commencement of
concrete placing, a test of the batching and mixing plant shall be made
in the presence of the Contracting Officer to check operational
adequacy. The number of full-scale concrete batches required to be
produced in trial runs shall be as directed, will not exceed 20, and
shall be proportioned as directed. All concrete produced in these
tests shall be wasted or used for purposes other than inclusion in
structures covered by this specification. All deficiencies found in
plant operation shall be corrected prior to the start of concrete
placing operations. No separate payment will be made to the Contractor
for labor or materials required by provisions of this paragraph. The
Contractor shall notify the Contracting Officer of the trial operation
not less than 7 days prior to the start of the trial operation.
m. Protection - The weighing, indicating, recording, and control
equipment shall be protected against exposure to dust, moisture, and
vibration so that there is no interference with proper operation of the
equipment.
3.1.2.4
Laboratory Areas
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NOTE: The editor should use the alternate sentence
and fill in the correct Section No. unless a
laboratory building is to be government furnished.
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SECTION 03700
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