2-SLCI26017 Attachment 2 Scope of Work.pdf

SCOPE OF WORK

SURFACE TREATMENT CHIP AND SLURRY AGGREGATE

The responsibilities of Contractor include, but shall not be limited to, the following.

A. Chip Seal Aggregate/Emulsion Compatibility testing must meet the requirements of the Wyoming Department of Transportation (“WYDOT”) standard for applicable AASHTO test methods, attached below.

B. Contractor shall provide grade “A” chip seal aggregate for City’s Street Division that meets or exceeds the American Public Works Association (APWA) standard specifications, section 32 0114 under chip seal as amended or superseded from time to time. This aggregate shall be 100 percent crushed stone or other high-quality particles or combinations with the following physical properties:

1. Grade A ½ inch minus chip seal aggregate.

2. Grade A chip aggregate must be compatible with CRS 2P emulsion.

3. Angularity (fractured faces): Greater than 60 percent of particles by weight with at least 2 mechanically fractured faces or clean angular faces, ASTM D 5821.

4. Hardness (toughness): Less than 30 percent wear of aggregate, ASTM C

131 unless specific aggregates having higher values are known to be satisfactory.

5. Weight Loss (soundness): For combined coarse and fine aggregate, ASTM

C 88.

a. Less than 12 percent using Na2SO4

b. Less than 18 percent using MgSO4

6. Polishing: Greater than 38, ASTM D 3319.

7. Flat or elongated Particles: 10 percent maximum of a 3:1 ratio for material retained above the 3/8-inch sieve, ASTM D 4791.

8. Friable Particles: Less than 3 percent by weight of aggregate passing the

No. 4 sieve, ASTM C 142.

9. Table 1 Gradation for chip seal: ASTM C 136. Graded by dry weight on a percent passing basis. Gradation must not vary from a high limit on one screen to a low on the next.

Table 1 – Master Grading Band and Target Tolerance Limits

Sieve Grade A Grade B Grade C

½ In. 100 - 100

3/8 in. 85-100 - 70-90

No. 4 0-20 - 0-5

No. 8 0-5 85-100 0-3

No. 16 - 10-25 -

No. 50 - 0-5 -

No. 200 0-1 0-2 0-2

NOTES:

(a) Portion retained on the No. 4 sieve clean and free of clay coatings.

(b) Portion passing No. 200 includes mineral filler, ASTM C 117

10. Table 2 Chip Seal Material: stone, slag or other high-quality particle or combination clean and free from organic matter or other detrimental substances with the following properties.

C. Contractor shall provide Type II ¼ minus slurry seal aggregate.

1. Type II slurry sand must be compatible with CQS 1H and CQS 1H 3% latex.

Table 2 – Aggregate Properties

Standard Min Max

Angularity (fractured faces), percent D 5821 80 -

C 131 - 35

Wear (hardness or toughness), percent C 88 - 10

Soundness (weightloss in 5 cycles), percent

Clay content

(sand equivalent), percent

SS Type I D 2419 45 -

SS Type II D 2419 55 -

SS Type II D 2419 60 -

Polishing, BPN D 3319 28 -

Water absorption, percent - - 1.25

NOTES:

(a) Angularity of aggregate retained on No. 4 sieve with at least one (1) mechanically fractured face or clean angular face. Provide 100 percent (maximum) for thoroughfares with a Road Class III.

(b) Wear of aggregate retained on No. 12 sieve after 500 revolutions.

(c) Soundness for combined coarse and fine aggregate measured using five (5) cycles

Na2SO4.

(d) Clay content before additives.

2. Table 3 Slurry Aggregate Gradation: Analyzed on a dry weight and percent passing basis.

a. Material passing angle sieve and retained on the next consecutive sieve is a 45 percent maximum.

b. Target Grading Curve must lie within one (1) of the following

Master Grading Bands. Field Samples shall not vary from the Target

Grading Curve by more than the Target Tolerance.

D. Contractor shall deliver product to City’s Delong Street stockpile location at 2350

West 750 South, Salt Lake City, Utah.

E. Contractor shall coordinate all delivery activity with City designee to ensure that a loader operator shall be available to facilitate movement of material to desired stockpile.

F. Orders shall be placed on an as needed basis. Contractor shall deliver all material ordered within five (5) business days after City places the order.

G. Contractor warrants that products furnished conform to the requirements specified and are of good merchantable quality and suitable for the purpose intended.

Table 3 – Master Grading Band and Target Tolerance Limits

Sieve Standard Master Grading Band Limits Percentage Target

Tolerance

SS Type

I

SS Type II SS Type

III

3/8 in.

C136

- 100 100 -

No. 4 100 90-100 70-90 +/- 5

No. 8 90-100 65-90 45-70 +/- 5

No. 16 65-90 45-70 28-50 +/- 5

No. 30 40-65 30-50 19-34 +/- 5

No. 50 25-42 18-30 12-28 +/- 4

No. 100 15-30 10-21 7-18 +/- 3

No. 200 C117 10-20 6-15 5-15 +/- 2

NOTES:

(a) Target tolerance is the allowable variation from Target Grading Curve.

(b) Portion retained on the No. 4 sieve clean and free of clay coatings.

(c) Portion passing No. 4 200 sieve includes mineral filler.

WYOMING DEPARTMENT OF TRANSPORTATION

CHIP SEAL AGGREGATE / EMULSION

COMPATIBILITY TEST

CHIP SEAL AGGREGATE AND SLURRY SEAL/EMULSION COMPATIBILITY TEST

A. General

a. This procedure describes the methods for determining compatibility of aggregate and emulsified asphalt for chip seals and establishes information to report prior to sealing operations. Compatibility is defined as the ability of aggregate to allow sufficient coating by emulsion residue and resist coating loss from adverse water exposure.

b. Ensure laboratories performing compatibility testing meet requirements of

(WYDOT) Standard Specification for applicable AASHTO test methods.

B. Responsibility of Contractor

a. Contractor shall perform compatibility testing prior to sealing operations.

Submit test data WYDOT Form T-180 to Resident Engineer.

i. Containers for mixing, having rounded corners, such as seamless tin cans, with the capacity to easily hold 100 grams of aggregate.

ii. Balance, with minimum capacity of 95 grams, accurate to 0.1 gram

iii. Spatula, steel, with a stiff blade approximately 25 mm wide by

100 mm long.

iv. Beaker, glass, 800 milliliter (mL).

Piece of aluminum window screen, cut in a circle to match bottom, inside diameter of 800 mL beaker.

v. Heat source, either hot plate or Bunsen burner, capable of maintaining 200 °F.

vi. Thermometer, stem range 180 °F to 220 °F.

vii. Brown Kraft paper, 50 lb. weight, square sheet; 12-inch x 12-inch, 18-inch x 18 inch.

b. Reference Documents

i. AASHTO R 66 Standard Practice for Sampling Asphalt

Materials

ii. AASHTO T 2 Sampling of Aggregates

iii. AASHTO 11 Material Finer than 75 µm (No. 2300) Sieve in mineral aggregate

iv. AASHTO T 59 Testing Emulsified Asphalts

v. WYDOT 409 WYDOT Standard Specifications

vi. WYDOT 803.1 WYDOT Standard Specifications

vii. WYDOT 803.8 WYDOT Standard Specifications

viii. WYDOT 803.9 WYDOT Standard Specifications

ix. WYDOT 804.1 WYDOT Standard Specifications

x. WYDOT 804.3 WYDOT Standard Specifications

xi. WYDOT 804.1.1 WYDOT Standard Specifications

xii. WYDOT T-180 Chip Seal Aggregate/ Emulsion Compatibility test

c. Procedure

i. Obtain approximately 100 ± 5 grams of clean, over-dried (no surface moisture) aggregate as required by project specifications.

For example, if the project requires gradation Type B for chip seal aggregate, obtain an aggregate sample from project sources

(s) that is well-graded from coarse to fine in accordance with

Table 803.8-1, Gradation Requirements: Chip Seal, 2010

WYDOT Standard Specifications.

ii. Obtain emulsion of same type as required by project specifications; thoroughly heat emulsion to 140 ± 5 °F; stir for 5 minutes or until uniform in consistency.

iii. Weigh 100 ± 5 grams of aggregate into a clean mixing container’ record weight as aggregate, A in grams, on Form T-180.

iv. Add 1% water aggregate (by weight of dry aggregate); mix until water is absorbed; record weight as water, W, in grams, on Form

T-180.

v. Determine quantity of emulsion to add to aggregate to achieve blend of 7% emulsion with 93% aggregate using the following equation:

E7% = (A÷0.93) – A

Where: A = Aggregate dry weight, grams (step 3)

E7% = Emulsion weight (7% blend), grams

vi. Add calculated quantity of emulsion (Step 5) to aggregate;

thoroughly and vigorously mix/blend emulsion and aggregate to maximize coating of aggregate, but not more than 5 minutes ± 15 seconds.

vii. After completely mixing aggregate and emulsion, empty container onto 18-inch x 18-inch square sheet of brown Kraft paper; spread out sample so all coated aggregate surfaces are clearly visible.

viii. Let coated aggregate cure at room temperature (60 °F to 80 °F) for 24 hours.

ix. Measure gross weight of coated aggregate & sheet (nearest gram); record as aggregate wight before boiling, AB Form T-180;

visually estimate percent coating (nearest 5%).

x. Record as percent coating before boiling, PB, on Form T-180 (the digit 1 denotes 1% water added to aggregate before emulsion coating).

xi. If PB (1) ≥ 85%, proceed with boiling sample (Step 14);

otherwise obtain new aggregate sample (per Step 1), repeat Steps

2 through 9 except add 2% water (Step 4).

xii. Record percent coating before boiling as, PB (2) Form T-180 (the digit 2 denotes 2% water added to aggregate before emulsion coating).

xiii. If PB (2) ≥ 85%, proceed of aluminum window screen on the bottom of 800 mL beaker to serve as a spacer to allow boiling water to contact full surface area of all coated aggregates

(including surfaces at the bottom of beaker).

xiv. Place circular piece of aluminum window screen on bottom of

800 mL beaker to serve as a spacer to allow boiling water to contact full surface area of all coated aggregates (including surfaces at the bottom of beaker).

xv. Add 600 mL of water into beaker.

xvi. Determine “mild boil” temperature, TB for water using the following equation (elevation adjusted):

TB = (-0.002 x E) + 205.1

Where: TB = Temperature, nearest degree F

E = Elevation of lab above sea level, nearest 10 feet

xvii. Heat water in beaker to temperature TB ± 5 °F (from Step 16);

verify temperature using stem thermometer inserted into water while heating.

xviii. Add entire coated aggregate sample (Step 9) to boiling water in beaker; measure weight of used 18-inch sample sheet and residue

(nearest gram); record as sample sheet & residue weight before boiling, SB, on Form T-180.

xix. Adjust/add heat to achieve TB ± 5 °F again (verify using stem thermometer); record as temperature of water, TW, on Form T-

180; leave coated aggregate sample in boiling water for 5 minutes ± seconds; record boiling times as, BT, on Form T-180.

xx. Drain water from beaker; let coated aggregate cool to room temperature (60 °F to 80 °F); measure weight of clean 12 inch x

12 inch square sheet of brown Kraft paper; record as sample sheet weight after boiling, SA, on Form T-180; empty beaker contents onto sample sheet; spread out sample so all coated aggregate surfaces are clearly visible.

xxi. Measure gross weight of coated aggregate & sheet (nearest gram); record as aggregate weight after boiling, AA, on Form T-

180; visually estimate percent coating (nearest 5%).

xxii. Record as percent coating after boiling, PA (x), on Form T-180

(where digit x denotes percent water added to aggregate before emulsion coating).

xxiii. Determine percent coating retained after boiling, PR(x), using the following equation:

PR(x) = (PB(x)) x 100%

Where:

X = percent water added to aggregate to achieve

85% minimum emulsion coating before coating

PR(x) = Percent coating retained after boiling, nearest 1%

PA(x) = Percent coating after boiling, nearest 5%

PB(x) = Percent coating before boiling, nearest 5%

xxiv. Record percent coating retained after boiling as, PR(x), on Form

T-180.

xxv. If PR(x) ≥ 80%, record aggregate/emulsion combination as

“Compatible” on Form T-180; if PR(x) <80%, record aggregate/emulsion combination as “Not Compatible” on Form

T-180.

d. General: Contractor shall provide materials for aggregate/emulsion combination (s) as follows:

i. Aggregate – Conform to requirements of Subsection 803.1, General; 803.8, Aggregate for Chip Seal, and Subsection 803.9, Aggregate for Blotter.

ii. Emulsified Asphalt – Conform to requirements of Subsection

804.3, Emulsified Asphalt.

iii. Water – Conform to requirements of Subsection 814.1.1, General.

e. Report: All test information on WYDOT Form T-180 (see blank form this section) including the following:

i. Aggregate; source location (e.g., Granite Canyon Quarry, Underpass Pit, etc.)

Gradation type (B, C, E, K, or S)

Gradation data (% Passing, sieves size)

Dry sample weight, A

Weight (coated) before boiling, AB

Weight, sample sheet & residue, before boiling, SB

Weight, sample sheet, after boiling, SA

Weight (coated) after boiling, AA

ii. Coating (emulsion residue);

Percent before boiling, PB

Percent after boiling, PA

Percent retained after boiling, PR

iii. Water;

Source added to aggregate (e.g., City of Cheyenne, etc.)

Weight added to aggregate (T1%, 2,) W

Temperature (boiling, elevation adjusted), TB

Temperature (boiling, water), TW

Boiling time, BT

iv. Emulsified Asphalt;

Emulsion Contractor

Emulsion type/grade (e.g., CRS-2P) Modifier type (latex, solid)

Blend sample weight, E7%

v. Aggregate/Emulsion Compatibility

Aggregate moisture, %

(to achieve 85% coating before boiling and 80% coating retained after boiling)

vi. Contractor shall provide all information required by Form T-180 to the laboratory (e.g., emulsion Contractor) performing compatibility testing. This information includes WYDOT project number, project location, name of WYDOT resident engineer, name of aggregate source, aggregate sample gradation type, and data, date when aggregate was sampled, company that tested and graded the aggregate, Contractor name, address, name of contact, and phone number.

vii. Testing Laboratory shall perform compatibility testing, record all data on Form I-180, sign, print name, date the completed Form

T-180 at the bottom right, and submit to Contractor for review, signature, printed name, and date (bottom left).

viii. Contractor must submit completed, signed, and dated Form T-

180 to WYDOT Resident Engineer at least three working days prior to chip sealing operations.