### **ITEM P-603 BITUMINOUS TACK COAT**

DESCRIPTION

**603-1.1** This item shall consist of preparing and treating a
bituminous or concrete surface with bituminous material in accordance
with these specifications and in reasonably close conformity to the
lines shown on the plans.

MATERIALS

**603-2.1 BITUMINOUS MATERIALS.**  The bituminous material shall be
either cutback asphalt, emulsified asphalt, or tar and shall conform to
the requirements of Table 1.  The type, grade, controlling
specification, and application temperature of bituminous material to be
used shall be specified by the Engineer.

**TABLE 1. BITUMINOUS MATERIAL**

Application Temperature

Type and Grade Specification Deg. F Deg. C

Emulsified Asphalt

  SS‑1, SS‑1h ASTM D 977 75‑130 25‑55

  CSS‑1, CSS‑1h  ASTM D 2397 75‑130 25‑55

Cutback Asphalt

  RC‑70 ASTM D 2028 120‑160 50‑70

Tar

  RTCB 5, RTCB 6 AASHTO M 52 60‑120 15‑50

CONSTRUCTION METHODS

**603-3.1 WEATHER LIMITATIONS.**  The tack coat shall be applied only
when the existing surface is dry and the atmospheric temperature is
above 60°F (15°C).  The temperature requirements may be waived, but only
when so directed by the Engineer.

**603-3.2 EQUIPMENT.**  The Contractor shall provide equipment for
heating and applying the bituminous material.

The distributor shall be designed, equipped, maintained, and operated so
that bituminous material at even heat may be applied uniformly on
variable widths of surface at the specified rate.  The allowable
variation from the specified rate shall not exceed 10 percent. 
Distributor equipment shall include a tachometer, pressure gages,
volume‑measuring devices or a calibrated tank, and a thermometer for
measuring temperatures of tank contents.  The distributor shall be
self‑powered and shall be equipped with a power unit for the pump and
full circulation spray bars adjustable laterally and vertically.

If the distributor is not equipped with an operable quick shut off
valve, the tack operations shall be started and stopped on building
paper. The Contractor shall remove blotting sand prior to asphalt
concrete lay down operations at no additional expense to the owner.

A power broom and/or blower shall be provided for any required cleaning
of the surface to be treated.

**603-3.3 APPLICATION OF BITUMINOUS MATERIAL.**  Immediately before
applying the tack coat, the full width of surface to be treated shall be
swept with a power broom and/or airblast to remove all loose dirt and
other objectionable material.

Emulsified asphalt shall be diluted by the addition of water when
directed by the Engineer and shall be applied a sufficient time in
advance of the paver to ensure that all water has evaporated before any
of the overlying mixture is placed on the tacked surface.

The bituminous material including vehicle or solvent shall be uniformly
applied with a bituminous distributor at the rate of 0.05 to 0.15
gallons per square yard (0.24 to 0.72 liters per square meter) depending
on the condition of the existing surface.  The type of bituminous
material and application rate shall be approved by the Engineer prior to
application.

Following the application, the surface shall be allowed to cure without
being disturbed for such period of time as may be necessary to permit
drying out and setting of the tack coat.  This period shall be
determined by the Engineer.  The surface shall then be maintained by the
Contractor until the next course has been placed.  Suitable precautions
shall be taken by the Contractor to protect the surface against damage
during this interval.

**603-3.4 BITUMINOUS MATERIAL CONTRACTOR\'S RESPONSIBILITY.**  Samples
of the bituminous material that the Contractor proposes to use, together
with a statement as to its source and character, must be submitted and
approved before use of such material begins.  The Contractor shall
require the manufacturer or producer of the bituminous material to
furnish material subject to this and all other pertinent requirements of
the contract.  Only satisfactory materials so demonstrated by service
tests, shall be acceptable.

The Contractor shall furnish the vendor\'s certified test reports for
each carload, or equivalent, of bituminous material shipped to the
project.  The tests reports shall contain all the data required by the
applicable specification. If the Contractor applies the material prior
to receipt of the tests reports, payment for the material shall be
withheld until they are received. If the material does not pass the
specifications it shall be replaced at the contractor\'s expense. The
report shall be delivered to the Engineer before permission is granted
for use of the material.  The furnishing of the vendor\'s certified test
report for the bituminous material shall not be interpreted as a basis
for final acceptance.  All such test reports shall be subject to
verification by testing samples of material received for use on the
project.

**603-3.5 FREIGHT AND WEIGH BILLS.**  Before the final estimate is
allowed, the Contractor shall file with the Engineer receipted bills
when railroad shipments are made, and certified weigh bills when
materials are received in any other manner, of the bituminous materials
actually used in the construction covered by the contract.  The
Contractor shall not remove bituminous material from the tank car or
storage tank until the initial outage and temperature measurements have
been taken by the Engineer, nor shall the car or tank be released until
the final outage has been taken by the Engineer.  Copies of freight
bills and weigh bills shall be furnished to the Engineer during the
progress of the work.

METHOD OF MEASUREMENT

1.  The bituminous material for tack coat shall be measured by the
    **\[gallon (liter)\] \[ton (kg)\]**.  Volume shall be corrected to
    the volume at 60°F (15°C) in accordance with ASTM D 1250 for cutback
    asphalt, ASTM D 633 for tar, and Table

2.  IV‑3 of The Asphalt Institute\'s Manual MS‑6 for emulsified
    asphalt.  Water added to emulsified asphalt will not be measured for
    payment.

BASIS OF PAYMENT

**603.5-1**  Payment shall be made at the contract unit price per
**\[gallon (liter)\] \[ton (kg)\]** of bituminous material.  This price
shall be full compensation for furnishing all materials, for all
preparation, delivery, and application of these materials, and for all
labor, equipment, tools, and incidentals necessary to complete the item.

Payment will be made under:

Item P‑603‑5.1 Bituminous Tack Coat---per **\[gallon (liter)\]\[ton
(kg)\]**

MATERIAL REQUIREMENTS

+------------+---------------------------------------------------------+
| ASTM D 633 | Volume Correction Table for Road Tar                    |
+------------+---------------------------------------------------------+
|            |                                                         |
+------------+---------------------------------------------------------+
| ASTM D 977 | Emulsified Asphalt                                      |
+------------+---------------------------------------------------------+
|            |                                                         |
+------------+---------------------------------------------------------+
| ASTM D     | Petroleum Measurement Tables                            |
| 1250       |                                                         |
+------------+---------------------------------------------------------+
|            |                                                         |
+------------+---------------------------------------------------------+
| ASTM D     | Cutback Asphalt (Rapid‑Curing Type)                     |
| 2028       |                                                         |
+------------+---------------------------------------------------------+
|            |                                                         |
+------------+---------------------------------------------------------+
| ASTM D     | Cationic Emulsified Asphalt                             |
| 2397       |                                                         |
+------------+---------------------------------------------------------+
|            |                                                         |
+------------+---------------------------------------------------------+
| Asphalt    | Asphalt Pocketbook of Useful Information                |
| Institute  | (Temperature-Volume Corrections for Emulsified          |
|            | Asphalts)                                               |
| Manual     |                                                         |
| MS‑6       |                                                         |
|            |                                                         |
| Table IV‑3 |                                                         |
+------------+---------------------------------------------------------+

**END ITEM P-603**

**Intentionally Left Blank**