414.01 363 SECTION 414 – EMULSIFIED ASPHALT SLURRY SEAL AND MICRO -SURFACING
414.01 Description ................................ ................................ ................... 363
414.02 Materials ................................ ................................ ...................... 363
414.03 Composition of Mixture ................................ ............................... 364
414.04 Equipment ................................ ................................ .................... 370
414.05 Preparing the Existing Surface ................................ ..................... 373
414.06 Applying Slurry Seal and Micro -Surfacing ................................ . 374
414.07 Joints ................................ ................................ ............................ 377
414.08 Fog Seal Application ................................ ................................ .... 377
414.09 Weather Limitations ................................ ................................ ..... 377
414.10 Opening to Traffic ................................ ................................ ........ 378
414.11 Method of Measurement ................................ .............................. 378
414.12 Basis of Payment ................................ ................................ .......... 379
DESCRIPTION
414.01 Description
This work consists of the design, testing, construction, and quality control required to apply an emulsified asphalt slurry seal surface (slurry seal) or micro-surface. The slurry seal or micro -surface shall consist of a mixture of an approved emulsified asphalt, mineral aggregate, water, and specified additives or modifiers, properly proportioned, mix ed, and uniformly spread over a prepared surface. The cured slurry or micro -surface shall have a homogeneous appearance, and adhere firmly to the surface. MATERIALS
414.02 Materials
Provide materials as specified in: Mineral Filler (Portland Cement) ................................ ........... 901.01 414.03 364 Mineral A ggregate (Slurry Seal) ................................ ........ 903.12.A Mineral Agg regate (Micro -Surface) ................................ .. 903.12.B Emulsified Asphalt ................................ ................................ 904.03 Water ................................ ................................ ...................... 921.01 For a slurry seal, use a Type CQS -1h emulsified asphalt. For micro - surfacing, use a Type CQS -1hp emulsified asphalt. Ensure that no deleterious material is introduced into aggregate stockpiled at project site.
414.03 Composition of Mixture
At least 2 weeks before beginning work, submit a signed original of a mix design, performed by a qualified laboratory and covering the specific materials to be used on the Project, to the Materials and Tests Division for acceptance, together with representati ve samples of each ingredient to be used in the mixture. Identify the samples with information related to sources, type of materials, and project number. Once the materials are approved, make no substitutions without first testing and obtaining the approv al of the laboratory that prepared the mix design. Do not begin work until the Materials and Tests Division has evaluated and accepted the mix design. Provide a laboratory report showing the results of tests performed on individual materials and comparing their values to those required by this specification. Use job aggregates in all laboratory design tests. Mixing tests shall pass at the maximum expected air temperature in ISSA T113.
A.Slurry Seal
1.Testing. The laboratory report shall provide the information specified in Table 414.03 -1 for the slurry seal mixture. 414.03 365 Table 414.03-1: Quick-Set Emulsified Asphalt Slurry Seal Test Requirement Mixing Time Test, seconds at 77 °F (TB-113) 120 min Mix Time , at 50 and 100 °F (informational) Set Time Tests: 30-Minutes-Blotter Test (TB -102) no brown stain Displacement Test no displacement Water Resistance Test , at 30 minutes (TB -102) no discoloration Wet Stripping Test, % coating (TB -114) 90% min System Compatibility (TB -115) Pass Set Time Tests: 30 minutes (TB -139) 12 kg-cm min Early Rolling Traffic Time: 2 hours (TB-139) 20 kg-cm min Wet Track Abrasion Test, loss in g/ft2 (TB-100) 75 max, 6 -day soak For roadways having greater than 1,500 ADT, in addition to the tests specified in Table 414.03 -1, the mixture shall also meet the requirements specified in Table 414.03 -2 for the ISSA T109, Test Method for Measurement of Excess Asphalt in Bituminous Mixtures by Use of a Loaded Wheel Tester and Sand Adh esion. Table 414.03-2: Excess Asphalt (for Roadways with > 1,500 ADT) Roadway ADT Requirement 1,500 – 3,000 Maximum: 55 grams/psf sand adhesion, 1,000 cycles @ 125 lbs 3,000+ Maximum: 50 grams/psf sand adhesion, 1,000 cycles @ 125 lbs
2.Composition. Emulsified asphalt slurry seal shall consist of a uniform mixture of aggregate, emulsified asphalt, latex solids when shown on the Plans, mineral filler , and water. The emulsified asphalt manufacturer shall certify the c ompatibility of all i ngredients (including the mix set additive) of the mix. 414.03 366 The percent of residual asphalt based on the weight of the dry aggregate shall be between 7.5 and 13.5%, with a mixture control tolerance of plus or minus 0.50%. Ensure that the aggregate gradation and percent residual asphalt, as provided in the slurry seal design accepted by the Engineer, is maintained within the mixture control tolerances stated herein. The Contractor may add Portland cement to obtain the desired dispersion and working c haracteristics of the slurry provided that the addition of Portland cement is stated on the slurry seal design, does not exceed 3% of the weight of the aggregate, and has a mixture control tolerance of plus or minus 0.25%. Portland cement added for dispers ion of the slurry seal shall be a commercial quality, non -air entraining cement and shall not be considered as mineral filler for the purpose of satisfying the gradation requirements of the aggregate. Pre-wet the aggregate with a minimum amount of water be fore blending with the emulsified asphalt to obtain a fluid, homogeneous slurry mixture of the proper consistency. Do not add to the mix any additional water above that quantity required by the slurry seal mix design to obtain a more workable mixture.
B.Micro-Surfacing
1.Testing. The laboratory report shall provide the information specified in Table 414.03 -3 for the micro -surface mixture. 414.03 367 Table 414.03-3: Micro-Surfacing Test Requirement Mixing Time Test, sec onds at 77 °F (T-102) 120 min Mix Time, at 50 and 100 °F (informational) Set Time Tests: 30 minutes (T -139) 12 kg-cm min Early Rolling Traffic Time: 60 minutes (T-139) 20 kg-cm min Wet Stripping Test, % coating (T -114) 90% min Wet Track Abrasion Test, loss in g/ ft2 (T-100) 75 max 6 days 50 max 1 hour Measurement of Excess Asphalt (T -109) 50 grams/ft2 max Sand Adhesion, 1,000 Cycles at 125 lbs Classification Compatibility (T -144) 11 pt. min Loss on Ignition (LOI) Test, 407.03.E.3 (informational)
2.Composition. For the paving mixture, the design shall verify the functioning of the set regulating additives and shall present certified test results for the Engineer’s approval. Aggregate in the mixture shall be representative of material to be used on the Project. Obtain the Engineer’s approval of the design before using. Proportions for the design shall be within the limits specified in Table 414.03 -4. 414.03 368 Table 414.03-4: Micro-Surface Mixture Design Requirements Material Requirement Modified Emulsi fied Asphalt Residue by Dry Weight of Aggregates 5.0-9.0% Mineral Additive by Dry Weight of Aggregate 0.5%-3.0% Latex or Polymer Based Modifier 3% minimum and as required to provide the specified properties Mix Set Additive As required to provide the specified properties Water As required to produce consistency The Contractor may add Portland cement to obtain the desired dispersion and working characteristics of the mix, provided that the addition of Portland cement is stated on the micro -surface design, does not exceed 3% of the weight of the aggregate, and has a mixture control tolerance of plus or minus 0.25%. Portland cement added for dispersion shall be a commercial q uality, non-air entraining cement and shall not be considered as mineral filler for the purpose of satisfying the gradation requirements of the aggregate. Proportion the mixture to achieve the test strip requirements specified in 414.06.
C.Applicable Specifications Consider the specifications and test methods identified in Table 414.03-5 to be part of this specification. 414.03 369 Table 414.03-5: Applicable Specifications Title Source Mixing, Setting and Water Resistance Test to Identify “ Quick-Set” Emulsified Asphalts ISSA TB-102 Wet Track Abrasion of Micro Seals ISSA TB-100 Measurement of Micro -Seal Consistency ISSA TB-106 Test Method for Measurement of Excess Asphalt in Bituminous Mixtures by Use of a Loaded Wheel Tester ISSA TB-109 Outline Guide Design Procedure for Slurry Seal ISSA TB-111 Method to Estimate Micro -Seal Spread Rates and to Measure Pavement Macrotexture ISSA TB-112 Trial Mix Procedure for Slurry -Seal Design ISSA TB-113 Wet Stripping Test for Cured Slurry - Seal Mixes ISSA TB-114 Test Method to Classify Emulsified Asphalt/Aggregate Mixture Systems by Modified Cohesion Tester. Measurement of Set and Cure Characteristics ISSA TB-139 Classification Compatibility ISSA TB-144 Design, Testing and Construction of Micro-Seal ASTM D3910 Quantitative Extraction of Bitumen for Bituminous Paving Mixtures ASTM D2172 The blended asphalt mixture, when combined with aggregate and mineral filler, shall have the following characteristics:
1.Be capable of filling up to ½-inch wheel ruts in one pass.
2.Be capable of field regulation of the setting time.
3.Be suitable for nighttime pl acement. 414.04 370 EQUIPMENT
414.04 Equipment
Maintain all equipment, tools, and machines used to perform this work in satisfactory working condition. Have available at all times a device capable of determining aggregate moisture within 3 minutes. Immediately afte r loading, cover all trucks with a cover of canvas or other suitable material. Allow the cover to lap down along the sides and rear of the truck bed a minimum of 6 inches, and secure with tie downs at a maximum of 5-foot spacing along the sides and rear o f the truck bed. Before starting hauling operations, ensure that all trucks are equipped to meet these requirements. Provide power brooms, power blowers, air compressors, water flushing equipment, and hand brooms capable of thoroughly cleaning all cracks and the old surface. Provide hand squeegees, hand brooms, shovels, and other incidental equipment as necessary to perform work.
A.Mixing Equipment The mixing equipment shall be re -supplied with all materials while depositing the mixture on the roadway to pr ovide a continuous, non -stop surfacing operation. Produce the paving mixture in a self -propelled, front feed, continuous loading, mixing machine equipped with a positive, non-slipping aggregate delivery system and an interconnected, positive displacement water-jacketed gear pump to accurately proportion ingredients. Equip the mixing machine with an approved fines feeder that has an accurate metering device or method to introduce a predetermined amount of mineral filler into the mixer at the same time and l ocation as the mineral aggregate. Provide a spray bar to completely wet the aggregate dropping down to the pug mill with additive and water. The twin -shafted multi-blade pug mill shall be a continuous flow type and a minimum of 50 inches long. Introduce the emulsion above the third point of the mixer to ensure proper premixing of the aggregate, cement, additive, and water when the modified emulsified asphalt is added. Blade size and side clearances shall meet the equipment manufacturer’s recommendations . 414.04 371 Perform mixing in a manner that does not cause premature breaking of the emulsified asphalt. The mixing unit of the mixing chamber shall be capable of thoroughly blending all ingredients. Equip the mixer with a remote forward speed control at the back m ixing platform so the back operator can control forward speed and level of mixture in paving or rut box. Provide a computerized material monitoring system with integrated material control devices that are readily accessible and positioned so the amount o f each material used can be determined at any time. Provide a back-up electronic materials counter that is capable of recording running count totals for each material being monitored. Equip the mixer with a radar ground measuring device. Calibrate each material control device before each mix application and as often thereafter as the Engineer deems necessary. The computer system shall have the capability to record, display and print the following information:
1.Individual sensor counts for emulsion, ag gregate, cement, water, and additive
2.Aggregate, emulsion, and cement output in pounds per minute
3.Ground travel distance
4.Spread rate in pounds per square yard
5.Percentages of emulsion, cement, water , and additive
6.Cumulative totals of aggregate, emulsion, cement, water , and additive
7.Scale factor for all materials Ensure the computer system is functional at the beginning of work and during each calibration. Equip the mixing machine with a water pressure system and fog type spray bar, adequate for complete fogging of the surface ahead of the spreading equipment . The mixing machine shall include controls for proportioning and calibrating the aggregate feed. The aggregate feed device shall have a revolution counter, so that the amount of aggregate used may be determined at any time, and a positive locking feed gate. Provide an emulsion pump of the positive displacement type and equipped with a device that can be used to determine the amount of emulsion used at any time. Arrange the emuls ion pump, meter, and 414.04 372 piping to allow calibration of the meter by weighing a metered volume. The pump shall deliver the emulsion to the mixer box at a uniform rate, which shall not vary more than 2% from the required quantity. Equip the water pump with a m inimum of two valves. One valve shall establish the required water flow. The other valve shall be a quick acting valve to start and stop the water flow. The mixing machine shall have sight gauges located at the material storage tanks for the asphalt emul sion and water. Equip the mixing machine with approved metering devices that can be used for calibration purposes and for estimating the quantities of materials used during any one period. If the metering devices stop working properly, do not use the mixi ng machine until the necessary repairs have been made. Provide satisfactory means to allow positive interlocking control between the flow of aggregate from the bins and the flow of emulsion from the pump. Calibrate each mixing unit in the Engineer’s prese nce before starting construction. Document the individual calibration of each material at various settings, which can be related to the machine’s metering devices. When calibrating the emulsion system, run a minimum of three tests, with each test run bei ng a minimum of 40 gallons. To calibrate the aggregate delivery system, perform tests at three different gate settings, with two test runs at each gate setting and a minimum of 425 pounds per test run. To calibrate the filler (cement) delivery system, pe rform three tests at a minimum of 25 pounds per test. Use certified scales. Only use machines that have been calibrated and accepted by the Engineer to perform the work. The Engineer may require additional calibrations during the process of the work.
B.Spreading Equipment Attach to the mixer a hydraulically adjustable (adjustable while applying mixture) type spreader box with a positive screed adjustment for yield control and a positive adjustment for the joint matcher. The box shall be equipped with the following: ribbon flights mounted on an adjustable shaft to continually agitate and distribute the materials throughout the box; curb bumpers and replaceable runners with a minimum of 5 -foot long end runners; and a sufficient walkway to provide access to e ither side of the spreader box without walking through the freshly laid material. 414.05 373 The spreader box shall be heavy duty with cross bracing for rigidity and a manufacturer’s weight of not less than 1,400 pounds at a width of 12 feet. The box shall be capa ble of laying mix to a width of 14 feet. The equipment shall provide sufficient turbulence to prevent the mix from setting in the box or causing excessive side build -up or lumps. To prevent loss of mixture from the box, attach flexible seals, front and r ear, in contact with the road. Equip the full width application box with a secondary strike -off located approximately 2 to 3 feet behind the primary strike -off to minimize transverse corrugations. The secondary strike -off shall have elevation and width adjustments similar to the primary strike -off. It shall have a pivot point where it can be tilted for texturing or raised completely off the surface. Rut filling shall require a steel or high density strike -off on the spreading equipment, as approved by the Engineer, or the use of a rut box. Use a rut box for filling ruts in excess of 3/8 inches unless otherwise shown on the Plans. Operate the spreading equipment to prevent the loss of mixture on super - elevated curves. Spread mixture to fill cracks an d minor surface irregularities and achieve a uniform skid -resistant surface without causing skips, lumps, or tears in the finished mat. For slurry seals, the use of burlap drags or other drags necessary to obtain the desired finish requires the Engineer’s approval. Replace drags having excessive build -up. Keep drags in a completely flexible condition at all times. Do not use drags on micro -surfacing. CONSTRUCTION REQUIREMENTS
414.05 Preparing the Existing Surface
Immediately before applying the tack coat and mixture, remove all dust, dirt, vegetation, and other deleterious material from the existing surface by brooming, washing with water under high pressure, blowing w ith compressed air, or other approved methods. Obtain the Engineer’s approval of the cleaned surface before applying the tack coat and mixture. Remove all thermoplastic pavement markings flush with the existing surface before applying the tack coat. Establish stations at 1,000 -foot intervals on the entire project before placing materials. Clearly identify and maintain the stations until project completion. 414.06 374 414.06 Applying Slurry Seal and Micro -Surfacing
A.Application Before placing the mixture, apply a tack coat of SS -1h, CQS-1h, or CQS-1hp emulsion with an asphalt distributor. The tack coat shall consist of one part emulsion and three parts water. The application rate shall be 0.10 to 0.15 gallons per square yard of the diluted emulsion. The Engineer will determine the actual application rate. Apply the tack coat as specified in 403. Apply the emulsified asphalt slurry seal at a rate of 16 plus or minus 2 pounds per square yard based on dry aggregate weight unless other wise shown on the Plans. Vary the rate of application within the range specified above as required by the condition of the pavement to obtain a minimum thickness of 1/8 inch above the high points of the milled areas and ¼-inch thickness on unmilled areas. Apply micro-surface as follows:
1.Rut-fill Course. If a rut-fill course is specified, apply enough material to fill the wheel paths without excess crowning (overfilling). An excess crown is defined as 1/8 inches after 24 hours of traffic compaction. Appl y rut-fill courses in widths from 5 to 6 feet for each wheel path. Provide a smooth, neat seam where two rut-fill passes meet. Take care to restore the designed profile of the pavement cross -section. Feather the edges of the rut - fill course to minimize the use of excess material.
2.Leveling Course. If a leveling course is specified, apply at a rate of 14 plus or minus 2 pounds per square yard based on dry aggregate.
3.Surface Course. If a surface course is specified and it is placed over a leveling course, apply at a rate of 18 plus or minus 1 pounds per square yard based on dry aggregate. If a surface course is specified and it is not placed upon another micro -surfacing course, apply the paving mixture at a minimum rate of 22 pounds per square yard based on dry aggregate. Apply micro -surface at the rates as shown on the Plans for leveling and surface courses. 414.06 375 Apply the mixture based on dry aggregate weight as shown on the Plans. The maximum allowable speed of the machine shall be 130 feet per minute. The Engineer will determine the maximum allowable speed for rut filling. Place the final surface seal uniformly across the width of the traffic lane unless otherwise specified or directed. The action of the squeegee shall allow the mix to flow freely, leavin g a smooth, uniformly textured surface. Unless otherwise directed by the Engineer, pre -wet the surface with water by fogging ahead of the spreader box. Closely control pre -wetting to prevent water from accumulating to the point of running off or puddling. As the aggregate and emulsion are being loaded into the aggregate/emulsion support trucks or mixing machine, perform a final screening of the aggregate by sieving it through screening equipment capable of removing random oversize material. Ensure that the mixture is of the desired consistency when deposited on the surface. Add no additional elements to the mixture once placed. Ensure that a sufficient amount of mixture is carried in all parts of the spreader at all times to obtain complete coverage. Do not allow lumping, balling, or unmixed aggregate, or segregation of the emulsion and aggregate fines from the coarse aggregate. If the coarse aggregate settles to the bottom of the mix, remove the mix from the pavement. The mixture shall have proper cons istency to avoid excessive splattering and excessive free water. Do not spray water into the spreader box during lay down operations. Use hand tools, lutes, and squeegees to spread mix on areas not accessible to the machine spreading equipment. After curing, perform rolling with a pneumatic -tired roller for sections of pavement not to be exposed to traffic. The roller shall be equipped with tires with a pressure of 40 to 60 pounds per square inch. Demonstrate throughout the course of the Project that the number of trucking units being used is sufficient to ensure a continuous forward operation. Repeated stopping and starting of the machine will not be allowed.
B.Quality Control Produce a mixture that complies with the mix design and the qual ity control tolerances. Apply the slurry seal or micro-surface at the rates 414.06 376 shown on the Plans. Use the methods described in this section to measure compliance. Maintain all quality control documentation and make it available to the Engineer upon reques t or at the completion of the work.
1.Asphalt Content. Calculate the percent asphalt content of the mixture by randomly reading the equipment computer display a minimum of three times a day. The quality control tolerances from the mix design is plus or min us 0.5%.
2.Application Rate. Calculate the yield of the course being placed by randomly reading the equipment computer display a minimum of three times a day. The quality control tolerance from the specified application rate is plus or minus 2 pounds per s quare yard .
3.Documentation. Maintain a lot sheet as follows: Divide the Project into lots of each day’s production . For each lot, maintain a lot sheet, providing the following information:
1.Contract Number, Route
2.Date, Air Temperature , Pavement Surface Temperature
3.Control Settings, Calibration Values, Unit Weight of Emulsion ( pounds per gallon) , Percent Residue in Emulsion
4.Beginning and Ending Log Miles
5.Computer display readings for material usage (Beginning, Ending, and Total)
6.Length, Width, Total Area ( square yards ) of the construction completed for the day
7.Aggregate used (dry ton), Asphalt Emulsion used (ton), additives (gallon), water (gallon), and/or Portland Cement (ton) 414.07 377 (8) Application Rate of asphalt emulsi on, Combined Application Rate ( pounds per square yard )
9.Mix Design (Percent Portland Cement, Percent Emulsion, Percent Asphalt Cement)
10.Calibration Forms
11.Contractor’s Authorized Signature
4.Test Strip Construction. Prior to production applicatio n, place a 1,000 plus or minus 50-foot test section . Place the test strip at the same time as paving is to take place, night or day, and under the same ambient conditions. Ensure the test strip is able to carry normal traffic within 60 minutes. If norma l traffic cannot be carried, adjust the emulsion or mixture , and construct another test strip.
414.07 Joints
Prevent excessive build -up, uncovered areas, or unsightly appearance on longitudinal or transverse joints. Avoid excessive overlap on longitudina l joints. Provide spreading equipment of suitable width to produce a minimum number of longitudinal joints throughout the Project. When placing micro - surfacing, terminate the final center joint of the micro -surfacing at a point that will fall directly un der the final permanent centerline. Before opening to traffic, apply pavement markings meeting 716.06. Allow a maximum of 3 inches for overlap of the longitudinal lane line joints. Also, the joint shall have no more than ¼-inch difference in elevation when measured with a 10-foot straightedge over the joint. Extend final edge lines a minimum of 4 inches over the old longitudinal edge joint. Ensure straight lines along curbs and shoulders. Do not allow runoff on these areas. Keep lines at intersections straight to provide a neat appearance.
414.08 Fog Seal Application
Meet 403.05.
414.09 Weather Limitations
Only place micro -surface and slurry seal when the pavement surface temperature and the ambient air temperature are a minimum of 50 F and 414.10 378 rising. Do not apply micro -surface or slurry seal during foggy or rainy conditions. Limit placement to the period from April 1 to October 31.
414.10 Opening to Traffic
Micro-surface material shall cure sufficiently within 1 hour after application, and slurry seal material shall cure sufficiently within 2 hours after application, so that traffi c can be allowed on the pavement without damaging the surface. Do not allow traffic on the mixture until it has cured sufficiently to prevent pickup by vehicle tires. Maintain traffic control as necessary to prevent damage to the mixture. Repair damage to the mixture caused by traffic at no cost to the Department. COMPENSATION
414.11 Method of Measurement
The Department will measure:
1.Emulsified Asphalt Slurry Seal by the square yards complete in place and accepted.
2.Micro-Surfacing by:
a.The square yards complete in place and accepted; or by
b.The quantity in tons (dry) of aggregate, including mineral filler, and the quantity in tons of latex or polymer modified emulsion used in the accepted portion of the micro - surfacing, based on the calibrate d metering device affixed to the micro -surface mixing machine.
3.Bituminous Materials for Tack Coat and for Fog Seal by the ton of undiluted emulsion. The quantity for “Bituminous Material for Tack Coat”, Item No. 403.01, should be ¼ of the estimated application rate. The Department will not directly pay for latex or polymer additives when used and will consider their cost to be included in the price bi d for the respective items. For bidding purposes, assume the emulsified asphalt content for the slurry mix design is 15% . When Micro -Surfacing is bid by the square yard, assume 414.12 379 the design asphalt content is 12%. If the Engineer sets an emulsified asphalt content for slurry seal other than that stated above, the Department will make a price adjustment based on the emulsified asphalt content set by the Engineer and the invoice price of the emulsified asphalt F.O.B. the project delivery point. The Departmen t will calculate the price adjustment according to the following formula: PA = [IP × (DA – BA) × T] Where: PA = Price Adjustment IP = Invoice price of emulsified asphalt cement DA = Percent emulsified asphalt set on the mix design BA = Percent emulsified asphalt specified above to be used for bidding T = Total tons of aggregate for pr ice adjustment as determined by the metering system on the mixing machine The Department will make payment to the Contractor for additional emulsified asphalt as provided for above at the purchase price F.O.B. the project delivery point, as verified by invoice, with no compensation allowed for further handling or processing. The Department will be reimbursed from monies due the Contractor for a decrease in emulsi fied asphalt content in the amount equal to the purchase price F.O.B. the project delivery point.
414.12 Basis of Payment
A.General The Department will pay for accepted quantities, determined in accordance with 414.11, at the contract prices, complete in pl ace, which payment shall be full compensation for all equipment, materials, labor and incidentals necessary to complete the work.
B.Adjustments
1.Loss on Ignition (LOI). A price adjustment for LOI shall be applied on a project basis per 407.20.C.3 .
2.Specific Gravity. In cases where the Bulk SSD specific gravity of the mineral aggregate exceeds 2.80, the Department will adjust the 414.12 380 tonnage of mineral aggregate for payment by multiplying the tonnage of mineral aggregate used by a specific gravity of 2.80 an d dividing by the higher specific gravity. 415.01 381 SECTION 415 – COLD PLANING OF BITUMINOUS PLANT MIX PAVEMENTS
415.01 Description ................................ ................................ ................... 381
415.02 Equipment ................................ ................................ .................... 381
415.03 General Requirements ................................ ................................ .. 382
415.04 Surface Requirements ................................ ................................ .. 383
415.05 Method of Measurement ................................ .............................. 383
415.06 Basis of Payment ................................ ................................ .......... 384
DESCRIPTION
415.01 Description
This work consists of cold planing an existing bituminous plant mix pavement. EQUIPMENT
415.02 Equipment
Provide a power broom, a water truck, and a planing machine, as well as equipment to remove the material planed from the pavement. The planing machine shall be a power operated, self -propelled milling machine or grinder capable of removing bituminous concrete to the required width, depth, profile, cross -slope, and surface texture. The machine shall be capable of accurately establishing profile by referencing from either the existing pavement or from an independent grade control and shall have positive means for cont rolling cross -slope. The machine shall have a floating moldboard with sufficient down pressure to plane the milled surface. The machine shall have an effective means of removing cuttings from the pavement and for preventing dust from escaping into the ai r. When milling the Interstate or controlled access freeways, the planing machine shall be capable of restoring pavement profile with a non -contact leveling system. T he non-contact leveling system shall have a minimum of three sensors dispersed the length of the machine.
Source: Tennessee Standard Specifications for Road and Bridge Construction, 2021 Edition. Pages 372–389 of 1,072.