SECTION 401
3.11.1.9 Pavers used for all 403.11 Item work shall have a minimum weight of 28,000 lbs. and a minimum 8-foot
wheelbase.
3.11.2 Method Requirements
3.11.2.1 All courses shall be spread and finished to the required thickness by approved, self-contained, self-propelled
spreading and finishing machines (pavers). Pavers shall be provided with an adjustable, activated screed and shall be capable of
spreading the mixtures with a finish that is smooth, true to the required cross-section, uniform in density and texture, and free
from hollows, tears, gouges, corrugations, and other irregularities. Broadcasting behind the paver shall be held to a minimum.
Pavers shall be capable of spreading and finishing courses of the required thicknesses and lane widths. Horizontally oscillating
strike-off assemblies will not be approved.
3.11.2.2 The activated screed shall be of the vibrating or tamping bar type or a combination of both and shall operate without
tearing, shoving, or gouging the mixture. The activated portion of the screed shall extend the full width of the mixture being
placed in the traveled way and other areas with sufficient width to accommodate a paver. In other locations as permitted such as
narrow shoulders, tapers, and areas adjacent to curbs, non-activated extensions to the screed will be allowed. The paver shall be
equipped with a screed heater. The screed heater shall be used when starting a cold machine and for maintaining a suitable screed
temperature when needed.
3.11.2.3 Blaw Knox Pavers shall be equipped with the manufacturer’s material management kit. The paving Contractor
shall certify that this work has been done before using any Blaw Knox paver.
3.11.2.4 The paver hopper gates shall be adjusted to pass the correct amount of mix to the spreading screws so that the
screws operate more or less continuously. The height of material shall be maintained at a constant level in front of the screed, to
a point where approximately half of the auger shall be visible at all times.
3.11.2.5 When required by the Engineer pavers shall be equipped with the following automatic screed controls for each
paver:
1. Two 24 ft ski type devices or floating beams.
2. Two grade sensors.
3. Two short skis Gjoint matchers).
4. Slope sensing control for transverse slope.
The sensors for either or both sides of the paver shall be capable of sensing grade from an outside reference line or from the
surface using a ski type device and shall be capable of sensing transverse slope of the screed. The sensors shall provide automatic
signals that operate the screed to maintain the desired grade and transverse slope. Pavers shall not be used until the automatic
controls have been checked and approved by the Engineer.
3.11.2.6 The use of automatic grade and slope controls shall be required on all pavers.
3.11.2.7 Whenever a breakdown or malfunction of the automatic controls occurs, the equipment may be operated manually
for the remainder of the normal working day on which the breakdown or malfunction occurred. This method of operation must
meet all other specifications.
3.11.2.8 On projects or parts of projects where the Engineer deems that the use of automatic controls are impracticable,
some or all of the controls listed in 3.11.1.5 may be waived.
3.11.2.9 The forward speed of the paver shall be adjusted to the rate of the supply of materials so that the paver operates
without having to make stops except for emergencies. If the Engineer determines that the paving operations result in excessive
stopping of the paver, the Engineer may suspend all paving operations until the Contractor makes arrangements to synchronize
the rate of paving with the rate of delivery of materials.
3.11.3 Blank.
3.12 Compaction.
3.12.1 General. Unless an alternate compaction package is approved at the project pre-pave meeting, roller trains shall
consist of the equipment describe herein.
3.12.2 Method Requirements.
3.12.2.1 Immediately after the hot asphalt mix has been spread, struck off, and surface irregularities adjusted, it shall be
thoroughly and uniformly compacted by rolling. The initial tolling shall be done with a static or vibratory steel-drum roller.
Intermediate rolling shall be done by a pneumatic-tired roller. Final rolling shall be done with a static steel-drum roller ora roller
of the steel-drum three-axle type, locked. The completed course shall be free from ridges, ruts, humps, depressions, objectionable
2016 NHDOT
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