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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

2.02 BRICK MATERIALS:

A. — Brick shall be sound, hard, and uniformly burned brick, regular and uniform in shape and size, of
compact texture, and satisfactory to the Engineer. Bricks shall comply with ASTM C32, for Grade
SS, hard brick, except that the mean of five tests for absorption shall not exceed 8 percent by
weight.

B. — Rejected brick shall be immediately removed from the work and brick satisfactory to the
Engineer substituted.

C. Mortar shall be composed of portland cement, hydrated lime, and sand in which the volume of sand
shall not exceed three times the sum of the volumes of cement and lime. The proportions of
cement and lime shall be as directed and may vary from 1:1/4 for dense hard-burned brick to
1:3/4 for softer brick. In general, mortar for Grade SS Brick shall be mixed in the volume
proportions of 1:1/2:4-1/2; portland cement to hydrated lime to sand.

D. Cement shall be Type II portland cement as specified for concrete masonry.

E. Hydrated lime shall be Type S conforming to ASTM C207.

F. The sand shall comply with ASTM C144 specifications for "Fine Aggregate," except that all of the
sand shall pass a No. 8 sieve.

2.03 FRAMES, GRATES AND COVERS:

A. Castings shall be of good quality, strong, tough, even-grained cast iron, smooth, free from scale,
lumps, blisters, sandholes, and defects of every nature which would render them unfit for the service
for which they are intended. Contact surfaces of covers and frame seats shall be machined to
prevent rocking of covers.

B. _ Allcastings shall be thoroughly cleaned and may be subject to a careful hammer inspection at the
Engineer's discretion.

C. Castings shall be ASTM A48 Class 30B or better.

D. The surface of the manhole covers shall have a diamond pattern with the cast words
"DRAIN" or "SEWER," whichever 1s appropriate.

E. Manhole frames shall be 6-inch height with 32-inch covers for 30-inch openings, 370 pounds
minimum by EJIW, No. LA326-5-000 or approved equal.

G. Catch basin castings shall be NHDOT Standard 3-sided 8-inch frame with Alternate Grate - Type
B or approved equal.

H. — Catch basin frames set against curbing shall have three flanges only.

2022 Sewer Replacement Project Precast Manholes and Catch Basins

Nashua, NH 02631-4

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

10

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

The surface should be pre-wetted by fogging ahead of the spreader box when required by surface
and ambient conditions. The rate of application of the fog spray shall be adjusted during the day
to suit temperatures, surface texture, humidity, and dryness of the pavement surface.

The micro-surfacing mixture shall be of the desired consistency upon leaving the mixer and no
additional materials should be added. A sufficient amount of material shall be carried in all parts
of the spreader at all times so that a complete coverage is obtained. Overloading of the spreader
shall be avoided. No lumping, balling, or unmixed aggregate shall be permitted.

No streaks, such as those caused by oversized aggregate, will be left in the finished surface. If
excessive amounts of oversized aggregates appear in the mix, the job will be stopped until the
contractor proves to the Engineer that the situation has been corrected.

Joints

No excessive buildup, uncovered areas or unsightly appearances shall be permitted on
longitudinal or transverse joints. The contractor shall provide suitable width spreading
equipment to produce a minimum number of longitudinal joints throughout the project. When
possible, longitudinal joints shall be placed on lane lines. Half passes and odd width passes will
be used only in minimum amounts. If half passes are used, they shall not be the last pass of any
paved areas.

Mix Stability

The micro-surfacing mixture shall possess sufficient stability so that premature breaking of the
material in the spreader box does not occur. The mixture shall be homogeneous during and
following mixing and spreading. It shall be free of excess water or emulsion, and free of
segregation of the emulsion and aggregate fines from the coarser aggregate.

Hand Work

Areas which cannot be reached with the mixing machine shall be surfaced using hand squeegees
to provide complete and uniform coverage. The area to be hand-worked shall be lightly
dampened prior to mix placement. Care shall be exercised to leave no unsightly appearance
from handwork.

The same type finish as applied by the spreader box shall be required. Handwork shall be
completed immediately after the micro-surfacing mixture is discharged from the spreader box.

Lines
Care shall be taken to insure straight lines along curbs and shoulders. No runoff on these areas

will be permitted. Lines at intersections will be kept straight to provide a neat workmanship
appearance.

il

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

Rolling

If required by the Engineer, specified areas shall be rolled by a self-propelled, 5 to10 ton
pneumatic roller with a tire pressure of 50 PSI and equipped with a water spray system.

H. QUALITY CONTROL
Materials

The contractor will permit the Engineer to take samples of the aggregate and asphalt emulsion to
be used in the project at the Engineer’s discretion. Gradation and sand equivalency tests may be
run on the aggregate, and residual asphalt content test run on the emulsion. Test results will be
compared to specifications. Tests will be run by a qualified laboratory at the expense of the
Owner. The Owner must notify the contractor immediately if any test fails to meet the
specifications.

Micro-Surfacing Mixture

Samples of the mixture should be taken daily and may be taken directly from the mixing unit(s).
Consistency and residual asphalt content tests may be made on the samples and compared to the
specifications. Tests will be run by a qualified laboratory at the expense of the Owner. The
Owner must notify the contractor immediately if any test fails to meet specifications.

The Engineer may use the recorder and measuring facilities of the unit to determine application
rates, asphalt emulsion content, mineral and field control additives, and water.

Non-Compliance

If any two successive tests fail on the stockpile material, the job shall be stopped. It is the
responsibility of the contractor, at his own expense, to prove to the Engineer that the conditions
have been corrected. If any two successive tests on the mix from the same machine fail, the use
of the machine shall be suspended. It will be the responsibility of the contractor, at his own
expense, to prove to the Engineer that the problems have been corrected and that the machine is
working properly.

I. MEASUREMENT AND PAYMENT

Micro-surfacing will be paid by the square yard (SY) complete in place as measured in the field
to the nearest 0.1 SY. Payment for micro-surfacing includes full compensation for material,
labor, transportation, and equipment necessary to complete this portion of the Bid Schedule. A
price adjustment for liquid asphalt is provided in this contract as outlined in Item 900 Liquid
Asphalt Adjustment. No payment will be made for materials delivered but not placed.