1.1 Use the following specifications for preparing, constructing, and accepting Hot-Mix Asphalt (HMA) material properties. Base Course The base course is the layer of material placed on top of the subbase or subgrade that supports the wearing and binder courses. P-401 Mix Design • Mix design is based on Marshall criteria: - Use 75 blows if aircraft gross weight is 60,000 lbs. At the same time, the ultra-thin friction course based on cold . 40 Section 309: Superpave . This asphalt paving method statement is specifically constructed over concrete road slab as compared to pavement construction over sub base course. 4. However, they will have to be adjusted for the project conditions (weather, haul distances, etc.). 1.01 SECTION INCLUDES . Asphalt Base in Lieu of Stabilized Subgrade? Asphalt concrete base (ACB), also called asphalt treated base (ATB), is a dense-graded HMA with a larger nominal maximum aggregate size (1 inch) intended for use as a base course or binder course (see Figure 1). Division 400 - ASPHALT PAVEMENTS AND SURFACE TREATMENTS: Section Description (Download ) Revised; 401: Asphalt Concrete Pavement by Gyratory Mix Design Method: 3/25/2019: 402: Asphalt Concrete Pavement by HVEEM or Marshall Mix Design Method: 7/20/2015: 403: Asphalt Concrete: 11/5/2015: 407: Chip Seal: 8/1/2014: 408: Cold Recycled Asphalt Base . 10 sieve, uniform in quality throughout and free from dirt, organic, or other injurious matter occurring either free or as coating on aggregate.
or more.
A mix design is a unique recipe based on the characteristics of the particular ingredients to be used. Warm-Mix Asphalt being applied on Route 2012 near Spring Mills, Centre County. The basic concepts of the Marshall mix design method were originally developed by Bruce Marshall of the Mississippi Highway Department around 1939 and then refined by the U.S. Army. Use of any other PG asphalt binder must be approved by the State Construction and Materials Engineer. percentage of asphalt. Do not allow RAP to exceed 60% by weight of total aggregates for Asphalt Base Courses nor more than 50% by weight of total aggregates for Structural and Leveling Courses. It rests on the asphalt base course. Marshall Mix Design.
•Consult the District Construction Design Engineer prior to deciding to eliminate stabilized subgrade in design. Total time for foamed asphalt to settle to half of the maximum foamed volume. . xi section 209 removing and replacing base course and asphalt surfacing ... 159 section 210 excavation and embankment .. 161 MIXTURE DESIGN Tables 3 and 4 give Marshall method data for mixes A and B. Three specimens are prepared at each of the four percentages of the asphalt at 4.5%, 5.0%, 5.5%, and 6.0% (Percentage of weight of the total mixture). Base Course Mix...Type 2 (type 1 if approved by Engineer) .
Top coats and sealants also cost another $1 to $2.50 per square foot. This course is presented in a four part series designed to give construction industry and transportation agency personnel a better understanding of the various steps in performing an asphalt mix design to meet . To enhance the crack resistance of asphalt-treated base (ATB), a type of gapped and semiopened gradation ATB mixture, GSOG, was designed. It All asphalt concrete base courses should be specified in 0.5-inch (10 mm) increments. Aggregate shall conform to ASTM C 33 except for gradation. 3. ASPHALT PAVEMENT . . Asphalt Treated Base Class I 0.34 4 Bituminous Treated Aggregate Base 0.23 6 Asphalt Treated Base Class II 0.26 4 Cold‐Laid Bituminous Concrete Base 0.23 6 Cement Treated Granular (Aggregate) Base.
Figures 1 and 2 show the design curves for both mixtures. Treated Subgrade and Base Courses. E. Asphalt Base Course constructed will be as per the type and location shown on the construction plans and shall conform with the following provisions: 1. - 50 blows for < 60,000 lbs. If at all possible, avoid discrepancies from the mix design temperature of more than 25 degrees. No mixture will be accepted until the Engineer has given approval. SECTION 400 - ASPHALT PAVEMENTS SECTION 401 - QUALITY CONTROL/QUALITY ASSURANCE, QC/QA, HOT MIX ASPHALT, HMA, PAVEMENT 401.01 Description This work shall consist of one or more courses of QC/QA HMA base, intermediate, or surface mixtures constructed on prepared foundations in accordance with 105.03. This item is to be used in conjunction with both a surface and intermediate . HOT MIX ASPHALT BASE COURSE . Asphalt Concrete • Section 719: Polymer Modified Asphalt Concrete . Basic Mix Design Philosophy Asphalt binder content - As much asphalt as possible for • Durability • Fatigue resistance •Flexibility - Not so much asphalt to affect .
280-2.2 Course Aggregates: Meet the requirements of Section 901. When slag aggregates are used in the mix, the asphalt content shall be increased accordingly5 minimum 25 percent for an all slag mix. • 309.2 Materials - follows 409.2. Areas of permanent work requiring compacted asphalt concrete paving are indicated on design drawings. Ultra-thin asphalt overlay has become the mainstream measure of road preventive maintenance due to its good economic benefits and road performance. Foundation course of compacted mixture of coarse and fine aggregates, and asphalt binder. 2. asphalt base and surface course materials for gradation and asphalt content. asphalt base course thickness provides a comprehensive and comprehensive pathway for students to see progress after the end of each module. Unlike surface mixes, more than one lift of base mix may be placed on a project to obtain the designed base layer thickness.
Aggregate Base Course . Table 4-4.Thickness Design: Low Volume Secondary and Rural Roads A. Asphalt intermediate course is that part of the asphalt pavement immediately under the wearing course. Use of a bound stabilized base is required on all roadway construction, reconstruction, and rehabilitation projects except for: 1. development and review of hot mix asphalt (HMA) mixture designs. E. Specifying approved ingredients and mixtures. 926.02 MIX DESIGN Prepare a minimum of four Marshall or four gyratory compactor specimens at 0.5 percent increments for a range of asphalt contents; with at least one specimen above and one below .
The wet-dry and freeze-thaw tests are usually considered indicative of the structural competence and dura Do not start hot mix asphaltic concrete work until the Engineer has approved a job mix formula for the mixture to be used. Asphalt pavement comprises the combined thickness of all asphalt courses as defined in Clause 407.24 . 300 lbs. 450.2 Mix Selection. Provides individual specifications from AC 150/5370-10, Standards for Specifying Construction of Airports, including construction standards for general provisions, earthwork, flexible base courses, rigid base courses, flexible surface courses, rigid pavement, fencing, drainage, turfing, lighting installation, pavement rejuvenation The asphalt binder used is a PG 64-22 and shown in Figure 8-b. 280-2.1 Bituminous Material: Use Superpave PG Asphalt Binder or Recycling Agent meeting the requirements of 916-1.
• Alternate criteria based on Superpave Gyratory Compactor (SGC) are given in EB 59A. This is the means for extending the service life rehabilitating old or . The pavement design requires the proper hot mix asphalt paving mixtures for the base and surface pavements.
•The difficulty of achieving compaction of the first course placed on an unstable subgrade must be considered. Asphalt Layer. Asphalt treated base (ATB) is a dense-graded (but more permeable) HMA with a wide gradation band and lower asphalt content intended for use as a stabilizing base course and intended to be used in conjunction with a top/ wear course of street/ highway grade HMA (typically 1/2 inch or 3/8 inch HMA as currently defined by Washington state DOT specifications). The basic concepts of the Marshall mix design method were originally developed by Bruce Marshall of the Mississippi Highway Department around 1939 and then refined by the U.S. Army. mix asphalt placed directly on sub-base or existing HMA. The approved production mixes were tailor-designed for each unique structural and functional pavement need that they had to fulfill. Provide mix designs for all SMA, Superpave and 4.75 mm mixes to be used. These are good targets with which to start a project. design, its source code and the percentage allowed in the mix are listed in the mix design document. 2.04 HOT MIX ASPHALT BASE COURSE (BLACK BASE) A. Coarse Aggregate: Gravel or crushed stone, or combination thereof that is retained on No.
0.20 6 Soil‐Cement Base 0.15 6 Crushed (Graded) Stone Base 0.14 6 Macadam Stone Base 0.12 6 Use mixes designated as Asphalt Base Course Type 1 (ABC-1), Asphalt Base Course Type 2 (ABC-2) and Asphalt Base Course Type 3 (ABC-3). In addition to site paving benefits, ACB can be advantageous because it can provide:
HMA 19M64 Base Course 3) Binder Grade 4) Location within the payment 1) Nominal Maximum Aggregate Size (mm) Superpave Mix Selection 4.75 9.5 12.5 19.0 25.0 37.5. Field trips to an off-campus . NOTE: Refer to the Standard Specifications, Division 300 for HMA Base Courses and on 400 for HMA Surface and Divisi If a higher type PG asphalt binder is warranted, it shall be used in the surface mixture and the first lift of the underlying mixture. Asphalt Pavement. Asphalt Pavement Association Of Michigan Selecting the Right Mix Local Agency Programs HMA Selection Guidelines Base Course Binder Selection - Use PG 58-28 for Superior Region - Use PG 58-22 for all other Regions A Base Course is defined as: - All layers below 4" of the surface PART 1 G E N E R A L . 2. Reclaimer/stabilizers can be used both as a recycler, to pulverize asphalt surfaces and base layers and mix in new binders, but also as a soil stabilizer, to mix in lime, cement and . The material was an AC-20 grade asphalt, steam reduced at the company's Baltimore refinery.
GENERAL 442,Asphalt Concrete Surface Course, 9.5 mm, Type A or B, (446/8) 442,Asphalt Concrete Surface Course, 12.5 mm TypeA or B, (446/8) Intermediate Course Mixes 441,Asphalt Concrete Intermediate Course, Type 1, (446/8) 441,Asphalt Concrete Intermediate Course, Type 2, (446/8) 442,Asphalt Concrete Intermediate Course, 19 mm Type A or B, (446/8) Base . Job mix formulas (mentioned in Chapter 3) are not required. Bituminous Material Asphalt cements shall meet the requirements of AASHTO M 226, Grade AC-20, Table 2, except that the requirements for solubility in trichloroethylene and the percent loss on heating are deleted.
Asphalt stabilization results in more flexibility, compared to other base course materials and chemical stabilizers, and can be used alongside other additives. Resurfacing is the placing of one or more courses of hot mix asphalt over an existing hard surface pavement. The asphalt base course can be placed and used under traffic during initial construction.
This study considered the engineering properties of asphalt mixtures produced using a European specification for high-modulus asphalt mixtures and used as base course. This item shall consist of a base course mixture of compacted mineral aggregate and asphaltic material, constructed on an approved sub-grade, in accordance with the plans and specifications and in conformity with the lines and grades. The job-mix formula (mix B) was as follows: A valid MasterCard, Visa, Discover or American Express credit card will be required for on-line payment.. A base course can be stabilized or non-stabilized. mix design, a new mix design must be submitted. 4-07.3(2)A Mix Design 12 . SCOPE. One-Time Use. The Asphalt Institute's manual on mix design methods for asphalt concrete (22) provides a method to determine necessary mix design characteristics (such as stability, flow, and air voids content) for either the Marshall or the Hveem mix design methods. The following table should be used as a guide in selecting the appropriate asphalt mix. II. Aggregate friction rating for coarse mix and OGFC will be in accordance with Table 502-3. Warm-Mix Asphalt being applied in Patton Township, Centre County, as part
Asphalt Emulsion Mix Design (1) 1 per source and as required based on change in material Allow 15 days or contract specified time for mix design and testing after receiving proposed gradation from contractor. •The reasons for eliminating must be documented in the project file. Staged construction improves on-site conditions, . Article 1.2 Applicable Standards shoulders only, the mix design and/or JMF target value for Air Voids are to be adjusted to 2.5 percent." If it is not known whether the shoulders will be placed as a separate paving During mix design temperatures are specified for proper mixing and for compaction. A. Hot-Mix Asphalt Material Properties . Do not use RAP in Friction Courses. Currently, the Marshall method is used in some capacity by about 38 states. 280-2.3 Fine . 280-2 Materials. Submit an aggregate gradation that conforms to Table 501-3 along with the Certificates of Analysis required in 501.02.4. Asphalt mixes should be formulated according to current, state-approved mix designs. Students are already familiar-from previous courses- with the basic tests that determine aggregate properties. Asphalt Pavement Association Of Michigan Selecting the Right Mix Local Agency Programs HMA Selection Guidelines Base Course Binder Selection Use PG 58-28 for Superior Region Use PG 58-22 for all other Regions A Base Course is defined as. mixtures meeting the definition of base course, field regress air void content to 3.0 . The following table should be used as a guide in selecting the appropriate asphalt mix. The Colorado Department of Transportation (CDOT) has used reclaimed asphalt pavement (RAP) as a base on many projects as a reconstruction strategy. 406.3.1 Item 301 Asphalt Concrete Base, PG64-22.
Course topics include SuperPave and Stone Matrix Asphalt mix design, materials selection, test methods and specifications.