transverse joints in the existing pavement.
3.3.2
Requirements for Use of Mechanical Spreader
The allowable temperature range of mixtures, when dumped into the
mechanical spreader, shall be as directed by the Contracting Officer.
Mixtures having temperatures less than 105 degrees C 225 degrees F when
ready to dump into the mechanical spreader shall not be placed in the
mechanical spreader, but shall be wasted. The mechanical spreader shall be
adjusted and the speed regulated so that the surface of PFC will be smooth
and continuous without tears and pulls, and of such depth that, when
rolled, specified thickness is obtained. Placing of the mixture shall be
as nearly continuous as possible, and speed of placing shall be adjusted as
directed to permit proper rolling. If segregation occurs in the mixture
during placement, the spreading operation shall be suspended until the
cause is determined and corrected and the segregated mix is removed.
3.3.3
Placing Strips Succeeding Initial Strips
In placing each succeeding strip after the initial strip has been spread
and rolled, the screed of the mechanical spreader shall overlap the
previously placed strip and be set at a sufficient height, so that after
rolling a smooth uniform joint is obtained. Mixture placed on the edge of
the previously placed strip by the mechanical spreader shall be removed by
hand and wasted.
3.3.4
Handspreading in Lieu of Machine Spreading
In isolated small areas where the use of machine spreading is impractical,
mixture shall be spread by hand. Spreading shall be in a manner to prevent
segregation. Mixture shall be placed and spread uniformly with hot shovels
and smoothed with hot lutes in a loose layer of such thickness that, when
rolled, will conform to the required thickness.
3.4
ROLLING OF MIXTURE
Rolling shall begin as soon after placing as mixture will bear roller
without undue displacement. Delays in rolling freshly spread mixture will
not be permitted. Two complete passes with a 9 metric ton 10 ton
double-drum steel-wheel roller to properly seat the material shall be
applied to the PFC. Additional rolling shall be performed only if
directed. Deficiencies shall be corrected so that the finished course will
conform to requirements for thickness and smoothness specified. Thickness
and smoothness will be checked in each lot of completed pavement by the
Contracting Officer for compliance and will be evaluated as specified in
paragraphs THICKNESS AND SURFACE-SMOOTHNESS REQUIREMENTS and ACCEPTABILITY
OF WORK.
3.5
JOINTS
Joints between old and new pavements, between successive days' work, or
joints that have become cold shall be made to ensure continuous bond
between old and new sections of the course. Joints shall have the same
texture and smoothness as other sections of the course. Contact surfaces
of previously constructed PFC coated by dust, sand, or other objectionable
material shall be cleaned by brushing, or shall be cut back as directed.
The surface, against which new material is placed, shall be sprayed with a
uniform coat of bituminous material as specified in Section 02748A
BITUMINOUS TACK AND PRIME COATS. The tack coat shall be applied far enough
SECTION 02747
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