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Technical Specifications IFB0660-040617
2017 Pavement Preservation
Revised per Addendum #1

ITEM 203.112 — Street Patch
A. SCOPE

This work includes removing damaged asphalt by milling, saw cutting, or jack hammering as
determined by the Engineer. If removal extends to the subbase, the subbase shall be compacted
to 95% density prior to placing new asphalt.

B. MATERIALS AND CONSTRUCTION

The Contractor shall furnish all materials, labor, equipment, and transportation necessary for
work in accordance with the latest approved City of Nashua Standard Specifications for Road
Construction, or the latest approved NHDOT Standard Specifications for Road and Bridge
Construction. The most stringent specification shall apply. Transportation and disposal of the
removed material shall be the responsibility of the Contractor.

This work includes milling, saw cutting, or jack hammering to remove damaged asphalt, and
compacting subbase to 95% density when required. Limits of work shall be marked by the
Engineer. Placement of asphalt will be under Item 403.12.

Contractor shall use a 1 ton steel drum roller or heavier to achieve required compaction. A hand
compactor shall be used to compact areas inaccessible to the roller.

C. MEASUREMENT AND PAYMENT

This item will be paid per Square Yard of asphalt placed and compacted as measured in the field.
No payment will be made for materials delivered and not placed. Payment shall include full
compensation for material, equipment and labor to complete this portion of the Bid Schedule.

Contractor shall measure the square yards of material placed and compacted for each street.
Payment is contingent upon submittal of quantities in a per street format.

Technical Specifications IFB0660-040617
2017 Pavement Preservation
Revised per Addendum #1

ITEM 304.112 - RECLAIMED STABILIZED BASE PROCESSED IN PLACE, 12” DEEP
A. SCOPE

This work shall consist of scarifying, if necessary, and pulverizing the existing pavement
together with subbase material to a depth of 12 inches, removal and disposal of excess reclaim
material, fine grading to elevations provided or as directed by the Engineer, and compaction of
materials to required densities. There will be approximately three inches of excess material to be
removed in order to accommodate three inches of asphalt. The material removed from this
operation shall remain the property of the City of Nashua and shall be transported and stock piled
by the contractor at the Four Hills Landfill at 830 West Hollis St in Nashua. This work will also
include installing and maintaining survey stakes at 25 foot intervals for edge of pavement and
centerline. Survey stakes shall be marked to clearly identify proposed elevations.

B. MATERIALS AND CONSTRUCTION

The Contractor shall furnish all materials, labor and equipment necessary for reclaimed
stabilized base, processed in place, in accordance with relevant provisions of section 306 of the
NHDOT Standard Specifications for Road and Bridge Construction, latest edition.

Compaction shall be accomplished using a vibratory sheep’s foot roller or pad foot roller with at
least 50,000 Ibs. of dynamic force. Final rolling shall be accomplished by a smooth steel wheel
vibratory roller with at least 27,000 Ibs. of dynamic force. Contractor shall also provide
compaction equipment sufficient to achieve required densities in areas not accessible by larger
equipment.

Fine grading to proposed grades shall be subsidiary. Removal, transportation, and disposal of
approximately 3” of material are subsidiary.

After site has been fine graded, compacted, and survey stakes installed, the Contractor will allow
1 day for grades to be verified. In no case shall paving be scheduled prior to verification of
proposed grades.

All catch basins must be protected from reclaimed materials by use of a silt sack. All materials,
labor, equipment, and transportation necessary to install, maintain, and remove the silt sacks
shall be subsidiary.

C. MEASUREMENT AND PAYMENT

Reclaimed stabilized base in place, 12 inch deep shall be paid by the square yard and shall
include full compensation for material, equipment, labor, and transportation required to complete
this portion of the Bid Schedule.

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Technical Specifications IFB0660-040617
2017 Pavement Preservation
Revised per Addendum #1

ITEM 403.11 - HOT BITUMINOUS PAVEMENT, MACHINE METHOD
A. SCOPE

This work shall consist of furnishing and placing bituminous pavement including shim pavement
to the depth shown on the plans or ordered by the Engineer.

B. MATERIALS AND CONSTRUCTION

The Contractor shall furnish all materials, labor, equipment, and transportation necessary for
work in accordance with the latest approved City of Nashua Standard Specifications for Road
Construction, and NHDOT Sections 401, 403, and 411 Modified By City of Nashua in Appendix
A. The most stringent specifications shall apply.

Surface preparation shall be subsidiary and shall include (but is not limited to) weed removal,
occasional pruning of trees, and removal of any vegetation impeding the placement of
bituminous pavement. The existing surface shall be thoroughly dry and swept free of all dust,
dirt and loose material (including winter sand).

A tack coat shall be applied immediately prior to placement of hot bituminous pavement. Tack
shall also be applied to every cold joint on driveways, side streets, and where directed by the
Engineer. Tack is subsidiary.

The Contractor shall prevent any materials from entering drainage structures and shall clean out
structures as directed by the Engineer if materials enter them.

The Contractor shall correct drainage problems, as directed by the Engineer, when problems can
be corrected by placing asphalt.

All pavement shall be of the same mix design.

Binder grade will be PG 64-28 unless otherwise specified by the Engineer.

Cc. MEASUREMENT AND PAYMENT

This item will be paid per Ton of placed, compacted, sampled, and cored hot bituminous
pavement, machine method as approved by the Engineer. No payment will be made for materials

delivered but not placed.

Contractor shall record the tons of material placed and compacted for each street. Payment is
contingent upon submittal of quantities in a per street format.

Technical Specifications IFB0660-040617
2017 Pavement Preservation
Revised per Addendum #1

ITEM 403.12 -HOT BITUMINOUS PAVEMENT, HAND METHOD
A. SCOPE

This work shall include paving using the hand method for areas where it is impractical to pave
using machine method, where shown on the plans, or as ordered by the Engineer.

B. MATERIALS AND CONSTRUCTION
The Contractor shall furnish all materials, labor, equipment, and transportation necessary for
work in accordance with the latest approved City of Nashua Standard Specifications for Road

Construction and NHDOT Sections 401, 403, and 411 Modified by City of Nashua in Appendix
A. The most stringent specification shall apply.

All surface preparation shall be subsidiary to this item. The existing surface shall be thoroughly
dry and swept free of all dust, dirt and loose material (including winter sand).

A tack coat shall be applied immediately prior to placement of hot bituminous pavement. Tack
shall also be applied to every cold joint, and where directed by the Engineer. Tack is subsidiary.

Contractor shall use a 1 ton steel drum roller or heavier to achieve required compaction.

Binder grade will be PG 64-28 unless otherwise shown on the plans or specified by the Engineer.
Asphalt mix design shall be approved by the Engineer.

Cc. MEASUREMENT AND PAYMENT

This item will be paid per Ton of placed and compacted hot bituminous pavement, hand method
as approved by the Engineer. No payment will be made for materials delivered but not placed.

Contractor shall measure the square yards of material placed and compacted. Street station and
offsets shall be included with each area measurement. Contractor shall record the tons of
material placed and compacted for each street. Payment is contingent upon submittal of
quantities in a per street format with respective station and offset values.

Technical Specifications IFB0660-040617
2017 Pavement Preservation
Revised per Addendum #1

ITEM 404.11 - MICRO-SURFACING
A. SCOPE

Work shall include all labor, materials, equipment, and transportation required for surface
preparation and placement of a thin overlay (micro-surface) as shown on the plans and as
directed by the Engineer.

B. MATERIALS

Emulsified Asphalt

The emulsified asphalt shall be a quick-set, polymer-modified cationic type CSS-1H emulsion,
and shall conform to the requirements specified in AASHTO M208 and ASTM 2397. It shall
pass all applicable storage and settlement tests. The polymer shall be milled into the emulsion,
or in the case of the HiMA (6% SBS) emulsion, may be blended into the unmodified base
asphalt. The cement mixing test shall be waived for this emulsion.

Fiber-Reinforced Micro-Surfacing Residue Properties

For fiber-reinforced mixtures, emulsion testing by distillation method (ASTM D5 or AASHTO
T49) shall yield Penetration values of between 40 and 120 dmm at 77 degrees F, and a Softening
Point (ASTM D36 or AASHTO T53) not less than 135 degrees F.

HiMA (6% SBS) Micro-Surfacing Residue Properties

For HiMA mixtures, emulsion testing by distillation method (ASTM D5 or AASHTO T49) shall
yield a Softening Point (ASTM D36 or AASHTO T53) not less than 170 degrees F.

Aggregate

The mineral aggregate used shall be of the type and grade specified for micro-surfacing. The
aggregate shall be manufactured crushed stone such as granite, slag, limestone, chat, or other
high quality aggregate or combination thereof.

Aggregate Physical Requirements

Grading: The aggregate including natural fines when tested by AASHTO methods T11 or T27
or ASTM C117 or C136, should meet the referenced gradation requirements.

Deleterious Substances: To limit the permissible amount of clay-like fines in an aggregate, a
sand equivalency value of 65 or higher is required when tested by ASTM 2419.

Soundness: The aggregate shall have a weighted loss of not more than 15% when the sodium
sulfate test is used, or 20% when the magnesium sulfate test is used.

Technical Specifications IFB0660-040617
2017 Pavement Preservation
Revised per Addendum #1

Hardness: The aggregate wear, from resistance to abrasion, shall be a maximum of 35% when
using AASHTO T96 or ASTM C131 test methods.
Water

The water shall be potable and shall be free of harmful soluble salts.

Modifier

Special quick-setting emulsifier agents shall be milled into the asphalt emulsion. The emulsified
asphalt shall be so formulated that when the paving mixture is applied at a thickness of one inch
with the relative humidity at not more than 50% and an ambient air temperature of at least 75
degrees F, the material will cure sufficiently so that rolling traffic can be allowed in one hour
with no damage to the surface, as verified by the Engineer.

Additives

A mineral additive shall be introduced to the aggregate and may be any recognized brand of non-
air entrained Portland cement or hydrated lime that is free of lumps, or other approved mineral
additive. It may be accepted upon visual inspection. The amount of mineral additive needed
shall be determined by the laboratory mix design and will be considered as part of the material
gradation requirement.

A liquid field control additive may be introduced and blended with water to provide effective
control of the required quick-set properties. This additive shall be made available by the
chemical supplier or emulsion manufacturer, and certified to be compatible with the mixture.

C. ENGINEERING

General

Before work commences, the contractor shall submit a signed and certified mix design covering
the specific material(s) to be used on the project. This design shall be performed by a qualified,
independent laboratory. Once the materials are approved, no substitution will be permitted
unless first tested and approved by the laboratory preparing the mix design.

Mix Design

The independent laboratory shall develop the job mix design and present certified test results for
the contractor’s and Engineer’s approval. Compatibility of the aggregate and emulsion shall be
verified by the mix design. The job mix formula shall meet standard ISSA A143 micro-
surfacing mix design requirements. All component material used in the mix design shall be
representative of the material proposed by the contractor for use on the project.

Technical Specifications IFB0660-040617
2017 Pavement Preservation
Revised per Addendum #1

Fiber-Reinforced Mix Design

Fiber-reinforced mix designs shall be tested for flexibility utilizing the TxDOT Overlay Test
(Tex-248-F) traditionally used for hot mix asphalts (HMA), and adapted for micro-surfacing as
follows:

1.) Section 2.1 -- constant maximum displacement should be increased from 0.025 in. to
0.050 in., 10 seconds (one cycle) to 60 seconds (one cycle).

2.) Sections 4.1 and 4.1.1 -- to be disregarded as they are solely intended for HMA.

3.) Section 4.2 — replaced in its entirety to read “Test Specimens — specimen length and
width must match Figure 1 (cutting template), and specimen height must be 0.50 in.
Make and cure the micro-surfacing overlay test specimens using similar methods and
resulting in similar mixture composition and mix consistency as done for the TB 100
(Wet Track Abrasion) and TB 147 (Loaded Wheel Test) specimens.

4.) Sections 5.1 and 5.2.3 — to be disregarded as they are solely intended for HMA.

5.) Section 5.3.1 — only the first sentence shall apply (“Mount and secure the base plates to
the mounting jig.”’)

6.) Sections 5.4 and 5.7.1 — change 77 degrees F to 41 degrees F.

7.) Section 5.7.2 — change 93% to 90% and add “specimens are required to meet 100 cycles
minimum before reaching the 90% reduction.”

In the event that new performance testing standards are developed to supersede the modified
TxDOT Overlay Test standards outlined above, such new standards shall be submitted and
approved by the Engineer.

Specifications

The Engineer shall approve the design mix and all micro-surfacing materials and methods prior
to use. The component materials shall be within the following limits.

Residual Asphalt 5% to 9% by dry weight of aggregate
Mineral Additive 0.5% to 3% by dry weight of aggregate
Polymer Modifier As required to provide specified properties
and Field Control

Additives

Water As required to produce consistency

Technical Specifications IFB0660-040617
2017 Pavement Preservation
Revised per Addendum #1

Fibers 0.05% to 0.25% by dry weight of aggregate as required to meet the
performance requirements of the TxDOT Overlay Test (Tex-248-
F) as described above

Aggregate - Recommended Gradations:

Type II Production

Screen Size % Passing Tolerance

3/8” 100 + 7.0/+7.0
#4 90-100 + 7.0
#8 65-90 + 4.0
#16 45-70 + 4.0
#30 30-50 + 4.0
#50 18-30 + 4.0
#100 10-21 + 4.0
#200 5-15 + 2.0

Suggested Application Rates:

Type II - Urban and Residential Streets and Airport Runways:
single course = 18-20 Ibs./s.y.
double course = 28-32 Ibs./s.y.

Note: all application rates above are dry aggregate weights exclusive of emulsion and all other
additives.

D. EQUIPMENT
General

All equipment, tools, and machines used in the performance of this work shall be maintained in
satisfactory working condition at all times to ensure a high quality product.

Mixing Equipment

The material shall be mixed by a self-propelled micro-surfacing mixing machine which shall be a
continuous flow, continuous run mixing unit able to accurately deliver and proportion the
aggregate, emulsified asphalt, mineral and field control additives, and water to a revolving multi-
blade twin shafted mixer, and discharge the mixed product on a continuous flow basis. The
contractor shall own and have available two (2) continuous flow, continuous run mixing
machines to ensure highest quality, and to mitigate the effect of equipment breakdowns. The
machines shall have sufficient storage capacity for aggregate, emulsified asphalt, mineral and
field control additives, and water to maintain an adequate supply to the proportioning controls.
The machines shall be equipped with self-loading devices which provide for the loading of
materials while continuing to lay micro-surfacing, thereby minimizing construction joints.

Technical Specifications IFB0660-040617
2017 Pavement Preservation
Revised per Addendum #1

Proportioning Devices

Individual volume or weight controls for proportioning each material to be added to the mix, i.e.,
aggregate, emulsified asphalt, mineral and field control additives, and water shall be provided
and properly marked. These proportioning devices are usually revolution counters or similar
devices, and are used in material calibration and determining the materials output at any time.

Emulsion Pump

The emulsion pump shall be a heated, positive displacement type pump.

Spreading Equipment

The surfacing mixture shall be spread uniformly by means of a mechanical type spreader box
attached to the mixer, equipped with paddles to agitate and spread the materials throughout the
box. The spreader box width shall be capable of adjustment while paving in order to
accommodate the changing width of some roadways without excessive overlaps. A front seal
shall be provided to insure no loss of the mixture at the road contact point. The rear seal and
secondary strike-off shall act as the final strike-off, and both shall be adjustable. The mixture
shall be spread to fill cracks and minor surface irregularities, and leave a uniform skid resistant
application of material on the surface. The spreader box and rear strike-off shall be so designed
and operated that a uniform consistency is achieved to produce a free flow of material to the rear
strike-off. The longitudinal joint where two passes join shall be neat in appearance, uniform and
lapped. All excess material shall be removed from the jobsite prior to opening the road. The
spreader box shall have suitable means provided to side-shift the box to compensate for
variations in pavement width and longitudinal alignment.

A rut box shall be available to pre-fill wheel ruts when necessary prior to overlay to eliminate
puddles or runoff interruption. The rut box shall be no less than 4’ wide and no more than 6’
wide.

Auxiliary Equipment

Suitable surface cleaning equipment, traffic contro! equipment, hand tools and any support
equipment shall be provided as necessary to perform the work.

Screening Plant

All aggregate shall be rescreened immediately prior to being loaded onto micro-surfacing
equipment. The screening plant shall be equipped with a 3/8” screen to remove all oversized
aggregate, and shall be capable of discharging screened aggregate directly onto the support
equipment. Any material discharged onto the ground must be rescreened prior to use.

Machine Calibration

Each mixing unit to be used in the performance of the work shall be calibrated in the presence of
the Engineer prior to construction, or previous calibration documentation covering the exact

Technical Specifications IFB0660-040617
2017 Pavement Preservation
Revised per Addendum #1

materials to be used may be acceptable provided they were made during the same calendar year.
The documentation shall include the individual calibration of each material at various settings,
which can be related to the machine metering devices.

E. WEATHER LIMITATIONS

The material shall be spread only when the road surface and atmospheric temperatures are at
least 45 degrees F and rising, the weather is not rainy, and there is no forecast of temperatures
below 32 degrees F within 48 hours from the time of placement of the mixture.

F. SURFACE PREPARATION
General

The area to be resurfaced shall be thoroughly cleaned of vegetation, loose aggregate and soil,
particularly soil that is bound to the surface. Manholes, valve boxes and other service entrances
will be protected from the surfacing material with polyethylene sheeting. All services will be
uncovered upon completion of work.

Cracks in Surface

If required by the Engineer, pre-treat the cracks in the surface with a fiberized crack sealer prior
to the application of the micro-surfacing. Crack sealer shall be a polymer and crumb rubber
modified asphalt cement including not less than 3% polymers, 7% recycled tire crumb rubber (80
mesh), and 8% polyester fibers (PCRM + fibers). The modified asphalt cement incorporated in
the PCRM + fibers material must meet PG 64-28E MSCR testing requirements.

Tack Coat
The contractor shall be required to apply a tack coat on any heavily oxidized pavements, and on
high traffic roadways as directed by the Engineer. The tack coat shall consist of one part

emulsified asphalt (CSS-1H) and three parts water, and be applied with a distributor at a rate of
0.05-0.10 gallons per square yard.

G. CONSTRUCTION

Stockpile

Precautions shall be taken to insure that aggregate stockpiles do not become contaminated. The
mineral aggregate shall be re-screened prior to being directly loaded onto micro-surfacing
equipment.

General

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