401BITUMINOUS SURFACE TREATMENTS

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of daytime temperature, when the ground is frozen, or when the surface temperature is less than 32 °F {0 °C}. Bituminous Surface Treatment A (Prime Coat) shall not be placed when the air temperature is below 40 °F {4 °C}. All other bituminous surface treatments (B, C, D, etc.) shall not be placed when the air temperature is below 60 °F {15 °C}.

Aggregates spread when the temperature is 70 °F {20 °C} and above may be surface damp but not wet. Aggregates spread when the temperature is below 70 °F {20 °C} shall be surface dry. Aggregates found by the Engineer to contain excessive moisture or free water at the time of use shall be rejected. The above limitations shall not be waived unless approved in writing by the Engineer.

Loose material, dust, dirt, caked clay, or any foreign material shall be removed. Cleaning shall be continued until the surface is clean or, in case of application on a soil or aggregate surface, all the loose dirt is removed and the surfaces of the larger size aggregate in the road surface are exposed but not dislodged. All cleaning of the area to be treated shall be completed before any bituminous material is applied.

No bituminous material or treatment shall be applied until the base or underlying surface has been approved.

Bituminous materials used for each treatment shall be heated as previously noted. The material shall be maintained within the specific temperature range during application. Any material which has not been maintained within the specified range shall be rejected. The following temperature (°F {°C}) ranges shall apply: TYPE OF BITUMEN PRIME HOT APPLICATION Liquid Asphalt Binder 275 °F – 350 °F {135 °C - 175 °C} Cutback Asphalt RC-70, MC-30, MC-70, MC-250 100 °F – 150 °F {35 °C - 65 °C} RC-250 125 °F – 180 °F {50 °C - 80 °C} RC-800, MC-800 170 °F – 240 °F {75 °C - 115 °C} RC-3000, MC-3000 215 °F – 270 °F {100 °C - 130 °C} Emulsified Petroleum Resin Ambient Temperature Emulsified Asphalt 120 °F – 170 °F {50 °C - 75 °C} 120 °F – 170 °F {50 °C - 75 °C} Emulsified Asphalt With Polymer Additive - - - - - - 140 °F – 180 °F {60 °C - 80 °C} It is recommended that, in general, liquid asphalt binders be used June through September and either emulsified asphalt or cutback be used the remainder of the season. Emulsified Petroleum Resin prime will not be required to be heated and shall be applied at ambient temperature. No Emulsified Petroleum Resin prime shall be placed when the ambient temperature is below freezing.

The bitumen shall be applied uniformly over the area to be treated. Where the treatment width is 26 feet {8 m} or less, the entire width shall be treated in one application, unless otherwise directed. Where only a partial width is treated in one application, extreme care shall be used to ensure a slight overlap of adjacent treatments, but not in excess of 4 inches {100 mm}. BITUMINOUS SURFACE TREATMENTS 187

The spray bar shall be adjusted to the proper height for exact single or double overlap of spray area without partial overlap. Uniformity of discharge shall be checked before beginning application and at other times as directed. Streaked areas and any other areas lacking uniform distribution shall immediately be made uniform. In all cases the distributor shall be stopped before the application begins to run light (just before the distributor tank is completely empty). A method of making joints shall be used that will ensure that in beginning and ending the distribution of each load, a proper junction is made with the preceding and succeeding work without excessive bituminous material at the joints. In applying bituminous materials, the Contractor shall use effective means to protect structures, walls, curbs, etc. from discoloration or spattering.

Before applying a prime coat, the surface shall be prepared as provided in Subarticle 401.03(c) above and, if necessary, it shall be sprinkled with water. After the prime coat has been applied, the contractor shall keep all traffic off the road until, in the opinion of the Engineer, the prime coat is dry and cured. When directed, the Contractor shall, without extra compensation, spread the minimum necessary amount of approved clean, coarse sand over the bituminous prime to prevent its breaking up under traffic or to speed up curing. No overlying surface shall be placed until the prime coat has been approved by the Engineer. The Contractor shall, without extra compensation, maintain the prime treatment and the surface of the base intact until it is covered by an application of a surfacing material. Maintenance shall include satisfactory repair to all holes, ravels, depressions, and areas deficient in prime so that the prime surface shall be smooth and of uniform texture before placing of an overlying surface.

The size and amount of aggregate used shall be in accordance with provisions of Subarticle

401.01(b) for the type treatment required by the plans or proposal

Spreading of aggregate shall follow application of bituminous material as closely as practicable using mechanical aggregate spreaders; inaccessible areas shall be covered as directed. Sufficient aggregate to cover each distributor load, in loaded trucks along with an adequate crew of workmen equipped with brooms standing by, shall be at the site before bituminous application begins. Spreading of the aggregate shall begin and continue immediately behind the application of the bituminous material. However, if excessive rolling of the aggregate occurs during spreading, the Engineer may allow the chip spreader to delay slightly in order to hold aggregate rolling to a minimum. Rolling shall begin immediately behind the spreading operation. Sufficient rollers shall be furnished to ensure that the initial pass of the roller is made within five minutes of the spreading of the aggregate. Rolling shall be continuous, providing coverage of the entire area of treatment to ensure thorough embedment of the aggregate. Unless a sufficient number of rollers are in operation to complete the above requirement, the next load of bituminous material shall not be applied until the rolling of the previous application is completed. When the Engineer determines the aggregate has been thoroughly embedded, rolling shall cease and the Contractor shall, without delay, remove all excess aggregate from the treatment area.

When placing surface treatment "L", special emphasis will be placed on not allowing either public or construction traffic over the work while placing of the treatment; if this cannot be avoided, it shall be well-controlled and kept to a minimum. The sequence of placement of the material shall be as follows:

Subarticle 401.01(b).

surface should then be rolled with a light roller to key the aggregate with the asphalt.

and the aggregate is keyed to the asphalt. SLURRY SEAL COAT 188

401.04Maintenance and Protection of Surface and Traffic

Maintenance shall include immediate repair of any failures or defects that occur, repeated as often as is necessary to keep the surface continuously intact and acceptable. Maintenance shall be performed without direct compensation. Unless otherwise specified on the plans or in the proposal, the Contractor shall handle traffic through the work and over the surface except while bituminous material is actually being applied and covered with aggregate. It shall be his responsibility to take whatever steps are necessary or directed to protect both the work and the traveling public.

401.05Method of Measurement

Measurement will be made of the number of square yards {square meters} of accepted bituminous treatment, complete in place. The length shall be the actual length measured along the surface of the treatment. The width shall be the designated width of completed surface. Where the pay item specifies a prime coat plus an overlying treatment, the measurement will not include the additional width of the prime coat. Where the pay item specifies a prime coat only, the width will be the specified width of the prime coat.

401.06Basis of Payment

Payment for accepted bituminous surface treatment, or bituminous surface treatment with polymer additive, Pay Item No. 401-B, measured as provided above, will be paid for at the contract unit price per square yard {square meter} complete in place for the type of bituminous treatment specified in the proposal by the type designation letter or letters; except that adjustments in the contract unit price shall be made as follows: When changes in amounts of treatment materials are ordered as provided in Article 401.01, the contract unit price will be adjusted upward or downward accordingly. Adjustment will be based on the increase or decrease in amounts per square yard {square meter}, at the verified cost, f.o.b. delivery point plus 2 cents per gallon {0.5 cent per liter} for the bitumen, and the verified cost per square yard {cubic meter} for the aggregate delivered to the spreader. The contract unit price or adjusted contract unit price for the accepted area complete in place shall be payment in full for furnishing all material, placement of materials, maintenance thereof and for all equipment, tools, labor, and incidentals necessary to complete the work.

401-A Bituminous Treatment Type designation letter/letters, Type of bitumen, if specified - per square yard {square meter} 401-B Bituminous Treatment Type designation letter/letters, Type of bitumen, if specified (With Polymer Additive) – per square yard {square meter} SLURRY SEAL COAT

402.01Description

This Section shall cover the work of constructing a surface course approximately 1/8 to 3/8 of an inch {3 to 10 mm} in thickness placed on existing paved surfaces in accordance with these specifications and within reasonably close conformity to the lines, grades, and widths shown on the drawings and as specified.

402.02Materials

CQS-1h or CQS-1hp shall meet the requirements of Section 804.

Aggregate shall meet the appropriate requirements of Section 801 and 802 with lightweight aggregate and manufactured sand made from limestone added to the list of approved stones.

Filler, if required, shall meet the requirements of Section 805.

The water shall be potable and free from harmful soluble salt.