Section 404 Section 404 indicated or directed. It shall then be moved for its full depth and formed into a windrow of uniform section. The windrow shall then be spread, at the prescribed rate per square yard. While the surface is being compacted and finish ed, the edges shall be shaped to a neat line. 404.03.7--Compaction . Immediately after the mixtur e has been spread, it shall be thoroughly and uniformly compacted. Rolling shall extend over a period of three days after the initial rolling and shall consist of a minimum of two coverages each day.
404.03.8 Top Dressing. When a top dressing of aggr egate is specified, it shall be
applied immediately after the rolling of the surface course. The top dressing shall be applied at the rate specified and rolled as directed.
404.03.9 Surface Tolerances . The distance at any point from a 10 foot straight edge to
the surface shall not exceed three- sixteenths in ch. Lumps or depressions exceeding this tolerance shall be corrected by removing defective work and replacing with new material as directed.
404.04 Method of Measurement . Cold bituminous pavement of the type specified will
be measured by the square yard or ton. When measured by the ton, measurement will be as prescribed in Subsection 403.04.
404.05 Basis of Payment . Cold bituminous pavement will be paid for by the square
yard or ton. Payment on a tonnage basis will be as set out in Subsection 403.05, except no reduction in payment will be made for compaction. Payment will be made under: 404-A: ___” Cold Bituminous Pavement, Type _____ - per square yard or ton 404-B: Aggregate Top Dressing - per ton SECTION 405 – STONE MATRIX ASPHALT
405.01 Description . These specifications include general requirements that are
applicable to Stone Matrix Asphalt (SMA). This work consists of constructing one or more lifts of SMA pavement on a prepared surface in accordance with th e requirements of Sections 401 and 403 for Asphalt Pavements, with the exceptions set forth herein. The SMA shall meet the specific requirements for the mixture to be produced and placed in reasonably close conformity with the lines, grades, thicknesses and typical sections shown on the plans or established by the Engineer.
405.02 Materials .
405.02.1 Component Materials .
405.02.1 1--General. Component materials will be conditionally accepted at the plant
subject to later rejection if incorporated in a mixture or in work that fails to meet contract requirements.
405.02.1 2--Aggregates . The source of aggregates shall meet the applicable
requirements of Section 703. 405.02.1.2.1--Coarse Aggregate Blend. Mechanically fractured faces by weight of the combined mineral aggregate coar ser than the No. 4 sieve shall be 95 percent two or more fractured faces for all SMA mixtures. The maximum percentage by weight of flat and elongated particles, maximum to minimum dimension greater than 3, shall not exceed 20% for SMA mixtures. This shall be determined in accordance with ASTM D 4791, Section 8.4, on the combined mineral aggregate retained on the 3/8” sieve.
405.02.1 2.2--Fine Aggregate Blend. All SMA mixture fine aggregate blends shall have
a minimum fine aggregate angularity index of 44.0 (ASTM C1252, Method A). The minus No. 40 fraction of the combined aggregate shall be non-plastic when tested according to AASHTO T 90. The clay cont ent for the combined aggregate used in underlying layers shall not exceed 1.0 percent, and when used in top layers shall not exceed 0.5 percent by weight of the total mineral aggregate when tested according to AASHTO T 88.
405.02.1 2.3--Combined Aggregate Blend. All gradations will be based on percent
passing by volume and not mass. Refer to Mississippi Test Method MT-80 Stone Matrix Asphalt (SMA) Volumetric Mix Design, Section 11 for the procedure to calculate gradations based on volumes. The gradation requirements, by volume, for SMA mixtures are provided in the following table. Sieve Size Nominal Maximum Aggregate Size 19.0-mm 12.5-mm 9.5-mm Lower Control Upper Control Lower Control Upper Control Lower Control Upper Control 1-inch 100 100 3/4-inch 90 100 100 100 1/2-inch 50 74 90 100 100 100 3/8-inch 25 60 26 78 90 100 No. 4 20 28 20 28 26 60 No. 8 16 24 16 24 20 28 No. 16 13 21 13 21 13 21 No. 30 12 18 12 18 12 18 No. 50 12 15 12 15 12 15 No. 200 8.0 10.0 8.0 10.0 8.0 10.0
405.02.1 3--Bituminous Materials . Bituminous materials shall meet the applicable
requirements of Section 702 for the grade specified. A PG 76-22 asphalt binder shall be used for all SMA mixtures. The asphalt content (by weight of total mix) shall be based on the bulk specific gravity of th e combined aggregate blend (G sb) to ensure a constant asphalt binder volume in the mix for durability purposes. The relationship between G sb and the minimum asphalt binder content by weight of total mix is provided in the following table. Based on Minimum Asphalt Content by Volume of 6.0 Percent Combined Aggregate Bulk Specific Gravity, G sb Minimum Asphalt Content (%) Rounded Minimum Asphalt Content (%) 2.40 6.58 6.6 2.45 6.46 6.5 2.50 6.34 6.3 2.55 6.22 6.2 2.60 6.11 6.1 2.65 6.00 6.0 2.70 5.90 5.9 2.75 5.79 5.8 2.80 5.70 5.7 2.85 5.60 5.6 2.90 5.51 5.5 2.95 5.42 5.4 3.00 5.34 5.3 Minimum AC, % (mass) = 0.724*(G sb)2 – 5.98*G sb + 16.76 Tack coat shall meet the requ irements of Subsection 401.03.1.2. Emulsified asphalt shall not be diluted without approval of the Engineer.
405.02.1 4--Mineral Filler. Mineral filler shall meet the requirements of Subsection
703.16.
405.02.1 5--Hydrated Lime . Hydrated lime shall meet th e requirements of Subsection
714.03.2 for lime used in soil stabilization.
405.02.1 6--Asphalt Admixtures . Additives for liquid asphalt, when required or
permitted, shall meet the requirements of Subsection 702.08.
405.02.1 7--Polymers. Polymers for use in polymer modified asphalt pavements shall
meet the requirements of Subsection 702.08.3.
405.02.1 8--Stabilizing Fiber. Stabilizing fiber shall meet the requirements of
Subsection 714.07.
405.02.2 Blank.
405.02.3 Composition of Mixtures .
405.02.3 1--General . Unless otherwise specified or permitted, the SMA shall consist of
a uniform mixture of asphalt, aggregate, mi neral filler, stabilizing fibers, hydrated lime and, when required or necessa ry to obtain desired propertie s, antistripping agent and/or other materials. The total amount of crushed limestone aggregate, in the top lift, shall not exceed 50 percent of the total combined aggregate by weight. Hydrated lime shall be used in all SMA at the rate of one percent (1%) by weight of the total dry aggregate. The ag gregate, prior to the addition of the hydrated lime, shall contain sufficient surface moisture. If necessary , the Contractor shall add moisture to the aggregate according to the procedures set out in Subsection 401.03.2.1.2. The Contractor shall obtain a shipping ticke t for each shipment of hydrated lime. The Contractor shall provide the District Materi als Engineer with a copy of each shipping ticket from the supplier, including the date, time and weight of hydrated lime shipped. Mixtures will require the addition of an antistripping agent when the Tensile Strength Ratio (MT-63) and/or the Boiling Water Test (MT-59) fail to meet the following criteria. Tensile Strength Ratio (TSR - MT-63) Wet Strength / Dry Strength .............................................. 85 percent minimum Interior Face Coating ......................................................... 95 percent minimum Boiling Water Test (MT-59) Particle Coatin g ................................................................. 95 percent minimum Reclaimed asphalt pavement (RAP) or crushed reclaimed concrete may be used in the production of SMA in the percentages of the total mix by weight set out in the following table. SMA Mixture Maximum Percentage of RAP by total weight of mix 9.5-mm 10 * 12.5-mm 10 * * At a minimum, RAP shall be crushed, processed and/or screened such that the RAP material size does not exceed the nominal ma ximum sieve size for the mixture specified.
405.02.3 1.1--Mixture Properties. The mortar is defined as the combination of the
percent passing the 0.075 mm sieve, liquid asphalt binder, and the stabilizing fiber. Mix design and approval shall include mortar preparation and testing conducted in accordance with Mississippi Test Method MT-81. The mortar shall have a minimum unaged dynamic shear rheometer (DSR) G*/sin of 5.00 kPa, a minimum rolling thin film oven (RTFO) DSR G*/sin of 11.00 kPa, and a maximum pressure aging vessel (PAV) bending beam rheometer (BBR) s tiffness (S) of 1500 MPa. All mixes shall be designed according to Mi ssissippi Test Method MT-80. SMA mixes shall be designed with the Superpave gyratory compactor utilizing an N design of 75 gyrations. The design air voids and voids in the mineral aggregate for all SMA mixes are 4.0 and a minimum of 17.0 percent, respectively. The ratio of the voids in the coarse aggregate in the compacted mix (VCA mix) to the voids in the coarse aggregate as determined with the dry rodded unit weight test (VCA dr) shall be less than 1.0. The designed mixture shall have a draindown of less than 0.3 percent when tested in accordance with Mississippi Test Method MT-8 2, Draindown Determination for Stone Matrix Asphalt Mixtures.
405.02.3 2--Job Mix Formula . The job mix formula shall be established in accordance
with Mississippi Test Method MT-80. At least 10 working days prior to the propos ed use of each mixture, the Contractor shall submit in writing to the Engineer a proposed job-mix formula or request the transfer of a verified job-mix formula as set forth in th e latest edition of MDOT’s Field Manual for HMA and MT-80. The job-mix formula shall be signed by a Certified Mixture Design Technician (CMDT). The Department will perform the tests necessary for review of a proposed job-mix formula for each required mixture free of charge one time only. A charge will be made for additional job-mix formulas submitted by the Contractor for review. Review of the proposed job-mix formula will be based on percent maximum specific gravity at N Design, VMA @ N Design, ratio of voids in the Coarse Aggregate (VCA mix/VCA dr), draindown, mortar properties, resistance to stripping, and other criteria specified for the mixture. The mixture shall conform thereto within th e range of tolerances specified for the particular mixture. No change in properties or proportion of any component of the job-mix formula shall be made without permission of the Engineer. The job-mix formula for each mixture shall be in effect until revised in writing by the Engineer. A job-mix formula may be transferred to other contracts in accordance with conditions set forth in the Department's Field Manual for HMA. The Contractor shall not place any SMA prio r to receiving “tentative” approval and a MDOT design number from the Central Laboratory. When a change in source of materials, unsatisfactory mixture production results (such as segregation, bleeding, shoving, rutting over 1/8”, raveling & cracking) or changed conditions make it necessary, a new job-mix fo rmula will be required. The conditions set out herein for the original job-mix formula are applicable to the new job-mix formula.
405.02.4 Substitution of Mixture. Mixture substitution shall meet the requirements of
Subsection 401.02.4.
405.02.5 Contractor's Quality Management Program .
405.02.5 1-General. The Contractor's quality management program shall meet the
general requirements of Subsection 401.02.5.1.
405.02.5 2--Personnel Requirements. Personnel requirements shall meet the
requirements of Subsection 401.02.5.2.
405.02.5 3--Testing Requirements. As a minimum, the Contractor's quality
management program shall include the following:
a.Bituminous Material. Provide Engineer with samples in a sealed one quart metal container at the frequency given in MDOT SOP TMD-20-04-00-000.
b.Mechanically Fractured Face. Determ ine mechanically fractured face content of aggregates retained on the No. 4 siev e, at a minimum of one test per day of production.
c.Mixture Gradation. Conduct extraction tests for gradation determination on the mixture. Sample according to the frequency in paragraph (i) and test according to Mississippi Test Method MT-31.
d.Total Voids and VMA. Determine total voids and voids in mineral aggregate (VMA), at N Design, from the results of bulk specific gravity tests on laboratory compacted specimens. Sample according to the sampling frequency in paragraph (i) and test according to the latest edition of M DOT’s Field Manual for HMA.
e.Asphalt Content. Sample according to the sampling frequency in paragraph (i), and determine the asphalt content using one of the following procedures.
1.Nuclear gauge. (Missi ssippi Test Method MT-6)
2.Incinerator oven. (AASHTO T 308, Method A) Draindown tests shall also be co nducted according to Mississippi Test Method MT-82, at a minimum of one test per day of production.
f.Stripping Tests. Conduct a minimum of one stripping test at the beginning of each job-mix production and thereafter, at least once per each two weeks of production according to Mississippi Test Method: MT-63 and one stripping test per day of production according to Mississippi Test Method: MT-59. Should either the TSR (MT-63) or the boiling water (MT-59) stripping tests fail, a new antistrip additive or rate shall be established or other changes made immediately that will result in a mixture which conforms to the specifications; otherwise, production shall be suspended until corrections are made.
g.Density Tests. Conduct density tests as necessary to control and maintain required compaction according to Mississippi Test Method: MT-16, Method C (nuclear gauge), or AASHTO T 166.
h.Quality Control Charts. Plot the individual test data, the average of the last four tests and the control limits for the following items as a minimum: Mixture Gradation (Percent Passing) Sieves: 1/2-in, 3/8-in, No. 4, No. 8, No. 30, and No. 200. Asphalt Content, Percent Maximum Specific Gravity Total Voids @ N Design, Percent VMA @ N Design, Percent Keep charts up-to-date and posted in a readily observable location. Charts may be kept on a computer, however, the charts shall be printed out a minimum of once each production day and displayed in the laboratory. Note any process changes or adjustments on the Air Voids chart.
i.Sampling Frequency. Conduct those tests as required above at the following frequency for each mixture produced base d on the estimated plant tonnage at the beginning of the day. Total Estimated Production, tons Number of Tests 1-700 1 701-1400 2 1401-2100 3 2101+ 4
j.Sample Requirements. Obtain the asphalt mixture samples from trucks at the plant. Obtain aggregate samp les from cold feed bins or aggregate stockpile. Save a split portion of all mixture samples at the laboratory site in a dry and protected location for 14 calendar days. At the completion of the project, the remaining samples may be disposed of with the approval of the Engineer. The above testing frequencies are for the estimated plant production for the day. If production is discontinued or interrupted, the tests will be conducted at the previously established sample tonnage points for the materials that are actually produced. If the production exceeds the estimated tonnage, sa mpling and testing will continue at the testing increments previously established for the day. A testing increment is defined as the estimated daily tonnage divided by the required number of tests from the table in the above subparagraph (i). In addition to the above program, aggregate stockpile gradation tests (AASHTO T-11 and T-27) shall be conducted every other production day. Fine aggregate angularity tests (ASTM C 1252, Method A) shall be conducted on the first day of production and once for every eight production samples thereafter, with a minimum of one test per production week.
405.02.5 4--Documentation. Documentation shall be as required in Subsection
401.02.5 4.
405.02.5 5--Control Limits. The following control limits for the job mix formula (JMF)
and warning limits are based on a running average of the last four data points. Item JMF Limits Warning Limits Sieve - % Passing 1/2-in ± 5.5 ± 4.0 3/8-in ± 5.5 ± 4.0 No. 4 ± 4.0 ± 3.0 No. 8 ± 4.0 ± 3.0 No. 30 ± 4.0 ± 3.0 No. 200 ± 2.0 ± 1.5 Asphalt Content, % -0.3 to +0.5 -0.2 to +0.4 Total Voids @ N Design, % ± 1.3 ± 1.0 VMA @ N Design, % – 1.5 – 1.0
405.02.5 6-- Warning Bands. Warning bands are defined as the area between the JMF
limits and the warning limits .
405.02.5 7--Job Mix Formula Adjustments. A request for a JMF adjustment signed by
a CAT-II may be made to the Engineer by the Contractor. Sufficient testing data shall be submitted with the request to justify the cha nge. The requested change will be reviewed by the State Materials Engineer for the Department. If current production values meet the mixture design requirements, a revised JMF will be issued. Adjustments to the JMF shall conform to the latest edition of MDOT’s Field Manual for HMA. Adjustments to the JMF to conform to actual production shall not exceed the tolerances specified for the JMF limits. Regardless of such tolerances, any adjusted JMF gradation shall be within the range given in Subsection 405.02.1.2.3 for the mixture specified. The JMF asphalt content may only be reduced if the pr oduction VMA meets or exceeds the minimum design VMA requirements for the mixture being produced. 405.02.5.8--Actions and Adjustments. Actions and adjustments shall be as required in Subsection 401.02.5.8. 405.02.5.9--Trial Section. At the beginning of placement for each lift, the Contractor shall construct a trial section of a maximum of 400 tons of mix, for the purpose of establishing and evaluating consistent mixt ure properties and the compactibility of the mixture. The Contractor shall determine the production point at which the mix shall be sampled during trial section construction. This sample does not have to be selected by the formal random selection procedures used during actual production, but should be representative of the mix produced. Density tests shall be performed according to the procedures in Chapter 7 of MDOT’s Field Manual for Hot Mix Asphalt (First Day Production). The Contractor (QC) and the Department (QA) will conduct tests for mixture quality. A trial section is considered to be successful if the QC test results are within the Warning Limits (the testing indicates a pay factor of 1.0) and the QC tests comp are to the QA tests within the allowable differences set forth in Subsection 401.02.6.2. If the criteria for a successful trial section is not achieved, additional trial sections of at least 200 tons but not more than 400 tons shall be constructed until the criteria is achieve d, at which time full production can begin. In the event a successful trial section is no t accomplished by the completion of the second trial section, the Contractor will be required to construct additional trial sections at an offsite location. The Engineer reserves the right to have any trial section removed and replaced at no additional cost to the State, if the pay factor for any ch aracteristic for a trial section is less than 0.75. For actual payment purposes, a pay factor of 1.00 will be used for all first and second trial sections allowed to remain in place. Any required offsite trial sections will be constructed at no additional cost to the State. 405.02.6--Standard s of Acceptance .
405.02.6 1--General. The general requirements shall be as required in Subsection
401.2.6.1.
405.02.6 2--Assurance Progr am for Mixture Quality. The assurance program for
mixture quality shall be as required in Subsection 401.2.6.2.
405.02.6 3--Acceptance Proc edure for Mixture Quality. The acceptance procedure for
mixture quality shall be as required in Subsection 401.2.6.3. 405.02.6.4--Acceptance Procedure for Density . Each completed lift will be accepted with respect to compaction on a lot to lot basis from density tests performed by the Department. Material produced and placed du ring the trial section(s), if placed on the roadway, will be designated as separate lots. For normal production days, divide the production into approximately equal lots as shown in the following table. When cores are being used for the compaction evaluation, randomly obtain one core from each lot. When the nuclear density gauge is being used for compaction evaluation, obtain two random readings from each lot an d average the results (see Ch apter 7 of the latest edition of MDOT’s Field Manual for HMA). Additional tests may be required by the Engineer to determine acceptance of work appearing defi cient. The Contractor shall furnish and maintain traffic control for all compaction evaluations, including coring, required in satisfying specified density requirements. Lot Determination Daily Production - Tons 0-300 301-600 601-1000 1001-1500 1501-2100 2101-2800 2801+ Number of Lots 4 5
405.02.6 4.1--Roadway Density. The density requirement for each completed lift on a
lot to lot basis from density tests performed by the Department shall be 93.0 percent of maximum density. When it is determined that the density for a lot is below 93.0 percent but not lower than 91.0 percent of maximum density, the Contractor will have the right to remove and replace the lot(s) not meeting th e specified density requirements in lieu of accepting reduced paymen t for the lot(s). When it is determined that the density for a lot is above 96.0 percent, the Engineer shall notify the Contractor who will make plant adjustments to resolve the problem. When it is determined that the density for a lot is below 91.0 percent, the lot(s), or portions thereof, shall be removed and replaced in accordance with Chapter 7 of the latest edition of MDOT’s Field Manual for HMA at no additional cost to the State. A corrected lot will be retested for approval. No resampling will be performed when pavement samples are used for determining density. At any time the average daily compaction (the total of the percent compaction for the lots produced in one day divided by the total number of lots for the day) does not meet 93.0 percent compaction or more for two consecutive days, the Contractor shall notify the Engineer of proposed changes to the compac tive effort. If the average daily compaction does not meet 93.0 percent compaction or more for a third consecutive day, the Contractor shall stop production and construct another trial section to establish proper compaction procedures. Each lot of work found not to meet the density requirement of 93.0 percent of maximum density may remain in place with a reduction in payment as set out in the following table: PAYMENT SCHEDULE FOR COMPACTION Lot Density ** Pay Factor % of Maximum Density 1.00 93.0 and above 0.90 92.0 - 92.9 0.70 91.0 - 91.9 ** Any lot or portion thereof with a de nsity of less than 91.0 percent of maximum density shall be removed a nd replaced at no additional cost to the State. The compaction pay factors and mixture qua lity pay factor will each apply separately (See Subsection 401.02.6.3). However, the co mbined pay factor shall not be less than 0.50 for any mixture allo wed to remain in place.
405.03 Construction Requirements . Mississippi DOT has adopted the “Hot-Mix
Asphalt Paving Handbook” as the guideline for acceptable SMA construction practices.
405.03.1 Specific Requirements .
405.03.1 1--Weather Limitations . The mixture shall not be placed when weather
conditions prevent the proper handling and finishing or the surface on which it is to be placed is wet or frozen. At the time of placement, the air and pavement surface temperature limitations shall be equal to or exceed 55°F.
405.03.1 2--Tack Coat. Tack coat shall be in accordance with Subsection 401.03.1.2.
405.03.1 3--Blank.
405.03.1 4--Density . The lot density for all SMA pavement lifts, except as provided
below for preleveling, wedging [less than fifty percent (50%) of width greater than minimum lift thickness], ramp pads, irregular shoulder areas, median crossovers, turnouts, or other areas where the established rolling pattern cannot be performed, shall not be less than 93.0 percent of the maximum density based on AASHTO T 209 for the day’s production. If a job-mix formula adjustment is made during the day which affects the maximum specific gravity, calculate a ne w average maximum density for the lot(s) placed after the change. Pavement core samples obtained for determining density which have a thickness less than two times the maximum size aggregate permitted by the job-mix formula will not be used as a representative sample. Preleveling, wedging [less than fifty percent (50%) of width greater than minimum lift thickness], ramp pads, irregular shoulder areas, median crossovers, turnouts, and other areas where an established rolling pattern cannot be obtained shall be compacted to refusal densification.
405.03.2 Bituminous Mixing Plants .
405.03.2 1--Plant Requirements .
405.03.2 1.1--Cold Aggregate Storage. The cold aggregate st orage requirements shall
be in accordance with Su bsection 401.03.2.1.1.
405.03.2 1.2--Cold Aggregate Feed. The cold aggregate feed requirements shall be in
accordance with Subsec tion 401.03 .2.1.2.
405.03.2 1.3--Dryer. The dryer requirements shall be in accordance with Subsection
401.03.2 1.3.
405.03.2 1.4--Stabilizing Fiber Addition. For batch plants, fibers shall be added
(manually or automatic) to either the pugmill or the weigh hopper. At least one aggregate source shall be added prior to the fiber addition, if fibers are added to the weigh hopper. Otherwise, fibers shall be added to the pugmill immediately after the addition of all the aggregate and prior to the addition of the asphalt binder.
405.03.2 1.4.1--Manual Method. Provided it is demonstrated to the satisfaction of the Engineer that the proper dosage rate of the stabilizing fibers is uniformly distributed into
the mix, manual introduction of the fibers is acceptable when a batch plant is used to make the mix. When the fibers are available in prepackaged (weighed) containers, proper dosage may be pre-determined per batch. A device is required to interrupt mixture production and warn the plant operator if the operator manually feeding the fiber fails to introduce it properly. Manual introduction of fibers shall not be used in drum plants.
405.03.2 1.4.2--Automatic Method. The automatic method requires specialized
equipment that can accurately proportion and meter, by weight, the proper amount per batch for batch plants, or continuously and in a steady uniform manner for drum plants. Fiber, pelletized or loose, shall not be fed through the cold feed bins or through the RAP bins. These proportioning devices shall be interlocked with the plant system and controlled to +/-10 percent of the weight of the fibers requir ed so as to maintain the correct proportions for all production rates and batch sizes. During trial section construction, an equipment calibration check shall be performed to the sa tisfaction of the Engineer that shows the fiber is being accurately metered and uniformly distributed into the mix. These metering devices shall provide in-process high flow (>10 percent or more) and low flow (<10 percent or less) plant operator notificatio n and interrupt the mix production where the fiber rate is not properly controlled. The fiber metering system shall also provide a record of feed rate (weight or mass per time) and include a section a minimum of two feet long of translucent pipe for visual confirmation of consistent flow rates. Care shall be taken to ensure that the fibers are not entrai ned in the plant’s exhaust system. If there is any evidence of fiber in the bag-house or we t-washer fines, the liq uid asphalt binder line and/or the fiber line shall be relocated so that the fiber is captured by liquid asphalt binder spray and incorporated into the mix. If ther e is any evidence of clumps of fibers or pellets at the discharge chute, the contr actor shall increase the mixing time and/or intensity. This may entail extending the liquid asphalt binder and fiber feeding lines further into the drum. Note : Various stabilizing fiber suppliers have developed methodology and equipment for metering bulk loose and pelletized fiber into asphalt plants. Whenever the fiber supplier’s recommendations are more stringent th an this specification, the fiber supplier’s recommendations shall control.
405.03.2 2--Additional Requi rements for Batching Plants. Additional requirements
for batching plants shall be in accordance with Subs ection 401.03.2.2.
405.03.2 3--Addition al Requirements for Drum Mixing Plants . Additional
requirements for drum mixing plants shall be in accordance with Subsection 401.03.2.3.
405.03.2 4--Surge or Storage Bins . Normally the surge bins shall be emptied at the end
of each day's operation. During breakdowns or adverse weather conditions, the material may be stored for a period not to exceed thr ee (3) hours in a well-sealed, well insulated, heated bin.
405.03.3 Hauling Equipment. Hauling equipment shall be in accordance with
Subsection 401.03.3.
405.03.4 Bituminous Pavers. Bituminous pavers shall be in accordance with
Subsection 401.03.4.
405.03.5 Rollers . All rollers shall be self-propelled units capable of maintaining a
smooth and uniform forward and reverse speed as required for proper compaction. Pneumatic-tired rollers shall not be permitted for compacting SMA mixes. Rollers shall be equipped with adjustable scrapers, water tanks, mats and a device for wetting the wheels to prevent the mixture from sticking. Adhesion of the mixture to the rollers will not be permitted. The use of diesel fuel or gasoline for cleaning roller wheels, or to aid in preventing the mixture from sticking to the wheels, is prohibited.
405.03.6 Preparation of Grade. Grade preparation sha ll be in accordance with
Subsection 401.03.6.
405.03.7 Blank.
405.03.8 Preparation of Mixture. Mixture preparation shall be in accordance with the
requirements of Subsection 401.03.8. 405.03.9--Material Transfer Equipment. Except for the areas mentioned below, the material transferred from the hauling unit sh all be remixed prior to being placed in the paver hopper or insert by using an approved Materials Transfer Device. Information on approved devices can be obtained from the State Construction Engineer. Areas excluded from this requirement include: temporary wo rk of short duration, detours, bridge replacement projects having less than 1,000 feet of pavement on each side of the structure, acceleration and deceleration lane s less than 1,000 feet in length, tapered sections, transition sections (for width), shoulders less than 10 feet in width, crossovers, ramps, side street returns and other areas designated by the Engineer.
405.03.10 Spreading and Finishing. Spreading and finishing shall be in accordance
with Subsection 401.03.10.
405.03.11 Compaction . After the mixture has been spread and surface irregularities
corrected, it shall be thoroughly and uniformly compacted to the required line, grade, cross section and density. It is recommended that compaction of SMA mixtures be completed before the mat temperature drops to 250°F.
405.04 Method of Measurement . Stone matrix asphalt will be measured by the ton in
accordance with the requ irements of Subsection 403.04 for asphalt pavements.
405.05 Basis of Payment . Stone matrix asphalt, measured as prescribed above, will be
paid for by the ton in accordance with the requirements of Subsection 403.05 for asphalt pavements.
405.05.1 Price Adjustment for Thickness Requirement. Adjustments in price for
thickness shall be in accordan ce with Subsection 403.05.1.
405.05.2 Pay Items .
Payment will be made under: 405-A: Stone Matrix Asphalt, (1) - per ton Mixture
1.9.5-mm mixture, 12.5-mm mixture, or 19-mm mixture SECTION 406 - COLD MILLING
406.01 Description . This work consists of removal of pavement materials on the
roadway and shoulders by cold milling to the designated depth and, loading, hauling, and disposal of the milled materials by the Contractor in accordan ce with the plans and specifications, or as directed by the Engi neer. The milled su rface shall provide a desirable surface free from go uges, continuous grooves, ridges, oil film, and other imperfections of workmanship and shall have a uniform appearance. This work also consists of the removal of portions of existing pavement using a cold fine milling process to a nominal depth using grade control as specified on the plans or as directed by the Engineer. It shall also include the loading, hauling, and disposal of the milled materials by the Contr actor in accordance with the pl ans and specifications. The planed surface shall provide a textured surface suitable for repairs, paving, or as a temporary riding surface, whichever is specified.
406.02 Blank .
406.03 Construction Requirements .
406.03.1 Equipment . The equipment to be used for this work shall be a self-propelled
milling machine capable of removing a minimum width of four feet. The equipment shall have sufficient power, traction, and stability to remove material and maintain an
Source: Mississippi Standard Specifications for Road and Bridge Construction, 2017 Edition. Pages 308–319 of 1,113.