B HOT MIX, HOT LAID ASPHALTIC CONCRETE OPSS 313

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1 B OPSS GENERAL HL,, Mixture, and/or Mix, is hot mixed, hot laid asphaltic concrete, used for pavement construction and other uses. 1. HL 1 This dense graded surface course mix is used on main highways carrying in excess of 5000 AADT/2 lanes. It consists of traprock coarse aggregate and local fine aggregates. When economical, Dense Friction Course Mixes should be considered in lieu of standard HL 1 mixes. 2. HL 2 HL 2 hot mix material is used as: i) a levelling course laid on existing pavement in order to correct irregularities of lines, crossfall or superelevation, ii) a surface course used for special applications in low speed areas where a thin layer of asphalt is required. The placing of HL 2 is sometimes a design requirement for main highways, using conventional pavement design, interchanges, speed change lanes, widening of roadway in excess of 2.0 m and elsewhere as recommended by the Regional Geotechnical Section. When the widening is less than 2.0 m, the Regional Geotechnical Section may recommend another mix. HL 2 is not normally used for shoulders and intersecting side roads or for patrol yards, private or commercial entrances and deep strength pavement construction. Where the total of required HL 2 is less than 300 t, this material should not be used unless specifically recommended by the Regional Geotechnical Section. 3. HL 3 This type of mix is designated as a surface course mix for heavy and medium traffic roads. The coarse aggregate AAA(13.2 mm) has to meet the quality requirements of OPSS HL 4 This mix is mainly used in Northern Ontario and in some parts of Southern Ontario as a surface of binder course B

2 In Southern Ontario the used of HL 4 for surface and binder courses is based on the availability and quality of local aggregates and on traffic volumes. Therefore, HL 3 may be recommended to be used as an alternative. The maximum coarse aggregate size is 19 mm. 5. HL 8 This type of mix is used as a binder course and may be surfaced with any type of hot mix surface course. The maximum particle size is 26.5 mm. 6. HL 4 and 8 Open Binder Course These open graded mixes are designed as binder courses for use over concrete pavement to delay reflection cracking. The modification of these mixes will be specified in a special provision. 7. Temporary This mix is used for seasonal asphalt applications, usually on secondary highways/temporary detours, and not to be used on 400 series highways and QEW Non-Driving Pavement Asphalt Applications In addition to the use of mixes in the pavement structure, some of the above-mentioned types of hot mixes are also employed for the paving of shoulders and ditches and median strips, construction of asphalt curb and gutters, gutter outlets, spillways, sidewalks and repairs or patching of the existing pavement Paving of Private Entrances and Side Roads The limits of paving of entrances and side roads will be established by the designer, and the depth of paving decided by the Regional Geotechnical Section. Previously paved private entrances are to be restored to their former condition. Gravel entrances in urban areas are paved between the curb and gutter and sidewalk. In rural areas where curb and gutter is used, gravel entrances may be paved at the discretion of the designer Policy of Local Municipality The designer shall contact the local Municipality with regard to local established policies on paving of private entrances. The Ministry will normally apply the policy of that Municipality provided the extent of the work does not exceed the normal Ministry cost B

3 If the Municipality insists on the application of their policy and standards, then they must agree to accept any additional costs before the work is carried out Paving of Commercial Entrances Commercial entrances should be paved according to the Commercial Site Access Policy and Standards Manual and should be approved by the designer and Regional Geotecnical Section. The limits of paving will sometimes be determined by alignment, grade and cross-section. For paving of entrances behind curb and gutter refer to section Miscellaneous Deferral of Paving Operations pavement is not to be placed before it is required for vehicular traffic because: a) the pavement is vulnerable to be damaged by construction vehicles, b) capital is tied up unnecessarily, c) hot mix pavements depreciate in the absence of traffic. On contracts where the fine grading is completed but the roadway will not be placed into service for some time, no paving operation shall commence until needed. A note on the plans on complex freeway staging work or direction by special provision is necessary to prevent the premature paving operation Padding Padding of the existing roadway is sometimes required to restore the roadway opr superelevation crossfall or to remove other pavement distortions prior to resurfacing. Pavement types and depths are contained in the Pavement Design Report. See paragraph for documentation procedure Pavement Widening on Curves An additional amount of is to be considered when calculating the required paving on curves. The widths and details of the pavement widening on curves is to be obtained from the Geometric Design Standards for Ontario Highway Manual, Chapter D Paved Shoulders The warrant and design of fully or partial paved shoulders is documented in the Geometric Design Manual Chapter D. The depth and width of paved shoulders should be clearly shown on a typical section or on a table Asphalt Quantities on Pavement Widening Contracts Pavement widening of up to 0.5 m may require an additional amount of asphalt quantities due to outward shoving of the asphalt by compaction equipment. The decision to adjust hot mix quantities on these widening contracts is the responsibility of the Regional Geotechnical Section based on the need of the individual contract B

4 Resurfacing in Rock Blasting Areas On projects where there is rock blasting adjacent to existing pavement which is not listed for removal or resurfacing, it has been found that, irrespective of the type of protection employed, damage to the pavement usually resulted. Therefore, where widening of rock cuts with a height of 1.5 m or more above the roadway surface is required adjacent to existing pavement as noted above, an allowance for the resurfacing of that area of the highway exposed to falling rock will be made. In general, a minimum length of 40 m of surface course is required, with sections separated by less than 60 m being connected with a continuous course. The extent of applicability is subject to circumstances on a project specific basis Tender Items HL.. HL.. Modified Asphalt Cement HL 1-5.2% HL 2-6.5% HL 3-5.4% HL 4-6.0% HL 3A - 5.3% HL 4-5.4% HL 8-5.4% HL 4 and 8 Open Binder Course - 3.0% The percentage of asphalt cement shown above will vary in each Region with the gradation and type of aggregates chosen. The contractor will supply the asphalt cement on all contracts. For contracts which require more than 400 t of asphalt cement, the designer will include a special provision which will provide for a payment adjustment when the Ministry s asphalt cement price index at the time of paving varies by more than 15% from the asphalt cement price index at the time of tender opening. The penetration grade and the percent of asphalt cement is documented in the special provision provided in Chapter E of this manual Specifications Details of the work of production, placing and compaction of HL are contained in OPSS Special Provisions B

5 The designer should refer to Chapter E of this manual to review the special provisions applicable to these tender items Standards The designer must base his work on highway engineering standards pertaining to the above tender items. Pavement design related standards are contained in the OPSD 500 series. Pavement design depths are shown on pages B and B of this section. Cross section elements are illustrated in the 200 series Temporary Pavement Whenever a temporary hot mix pavement (detours, widenings, etc.), which is intended to be removed within the same construction season, is included into a contact package, the use of the special provision for Temporary Pavement should be considered. This special provision offers the Contractor the option to construct and repair hot mix used for Temporary Pavement which is not subject to the normal payment adjustments for asphalt cement content, aggregate gradation and pavement compaction, and is inserted into a contract package upon the recommendation of the Manager of the Regional Construction Office. This special provision should not be used for detours or other temporary placement, if it is expected that the time frame for the temporary pavement will extend beyond the same construction season. The Regional Geotechnical Section is to be consulted in the selection of the type of mix for the temporary hot mix pavement from the following mix types: HL 3, 4, 8 Recycled. See paragraph and for documentation procedure COMPUTATION Source of Information All paving requirements with respect to HL types and depths including the paving of shoulders as recommended by the Regional Geotechnical Section are stated in the Pavement Design Report Method of Calculation The unit of measurement for HL mixes is the tonne. Each type of asphalt paving mixture used on a project will form a separate tender item. The computed tonnage for each type is the product of the calculated area of paving in square metres. The applicable mass in kg for the required depth and tonnage per kilometre for various paving widths is shown in the table below Type of Mix B

6 Type of Mix Course Depth mm Kg/m2 1.0 m width Tonnes per kilometer 6.0 m width 6.5 m width 7.0 m width 7.5 m width HL kg/m2/ 10 mm deep HL kg/m2/ 10 mm deep HL 3, 4 & kg/m2/ 10 mm deep HL 4, & 8 Open Binder Course 23.5 kg/m2/ 10 mm deep The above figures are based on traprock course and local fine aggregates for HL 1 and local coarse and fine aggregates for HL 2, 3, 4 and DOCUMENTATION The type of each hot mix used and the recommended depths of the appropriate paving course must be indicated on the contract plans, profiles or typical sections. It is necessary to ensure that this information is indicated for all asphalt paving to be carried out on a project and must include the types and depths of paving courses for roadway, private and commercial entrances, side roads, detours, patrol yards, interchange ramps, pavement widening, paved shoulders, etc. When padding, temporary hot mix pavement or superelevation correction is requested for a project, the exact locations and required tonnages for each location where this work is B

7 to be carried out must be indicated by a note on the contract plans. In case of superelevation correction, the rate of proposed superelevation must also be shown. The hot mix quantities computed for the various parts of a project are summarized on the Quantities and Granular sheet with separate entries under the appropriate HL heading as follows: - Roadway (incl. Partial Paved Shoulders) - Commercial Entrances - Interchange Ramps - Private Entrances - Channelization Legs - Patrol Yards - Side Roads - Fully Paved Shoulders - Detours - Temporary, etc. - Medians, Islands - Paving Under Guiderails When any of the following tender items are being used on a project, the asphalt material designated for this work must be calculated in tonnes and indicated under the appropriate item as a separate line entry on the Quantity Sheet. - Asphalt Curb and Gutter - Asphalt Surfacing of Gutter - Asphalt Spillways - Asphalt Gutter Outlets - Asphalt Sidewalks - Sidewalk Resurfacing - Crack Repair The calculated quantities are recorded on the Quantities and Granular Sheets in tonnes, and totalled. This total is the tender total and is transferred to the Tender Document Documentation Accuracy Calculated hot mix quantities are recorded in tonnes to the nearest whole number. Stations are recorded to the nearest whole metre B

8 PAVEMENT THICKNESS TABLES Course Freeways and Arterials 2 Lane Highways Present Traffic AADT > > = Present Traffic AADT Asphalt Courses in Comp. Pav t Bridge Decks Asphalt S walk 1. Surface HL1,3or HL1,3 or 4 HL3 or 4 40 mm HL3 or 4 50 mm HL3 or 4 6. HL3 or 4 HL 1, 3 or 4 HL 1, 3 or mm HL 3 or 4 Binder 50 mm 1@40mm 1@50mm 2@40mm or 1@40mm 1@50mm 1@ 50 mm HL 4 or 8 Nil Nil 40 HL 4 or 8 40 HL 4 or 8 Nil Total Thickness mm or 130 mm Course Airport Runways Taxiways And Aprons 4. Paved Medians, Guide Rail Areas, Parking Areas and Islands Built up Area & Emergency Parking 7. No Parking Patrol Yards Service Centres and Parking Lots Buses and Trucks Cars 1. Surface HL2,3 or 4 50 mm Binder 50 mm 30mm HL4 or 40mm HL4 or 8 Nil 50 mm 50 mm Nil Total Thickness mm or B

9 3. 80 mm NOTES: 1. Thickness as shown with 30 mm minimum. 2. Thickness selected to be determined by traffic densities, growth potential, %truck traffic, etc. 3. For deep strength & full depth construction, consult OPSD Design suitable for aircraft up to DC3. For airports with low traffic or mainly aircraft use 40 mm thickness only or surface treatment. Loadings higher than DC3 require special consideration. 5. May be modified to be sandier or richer mm thickness to be used in Districts 1 to A single 50 mm course should be used for small, low traffic areas. 8. For urban freeways, open friction course 25 mm should be used. 9. For main highways carrying in excess of 5000 AADT/lane, dense friction course to be used. 10. For main highways carrying in excess of 5000 AADT/2 lanes, HL1 to be used except N Ont. A For full depth recycling use thicknesses shown. B When resurfacing existing pavements consult table on page B C Both through and approach lanes on truck inspection and freeway service stations shall have the same pavement as adjacent lanes on traffic lanes. Minimum totat thickness to be 100 mm. D Thicknesses shown are in millimetres of consolidated bituminous pavement. THICKNESS FOR CONVENTIONAL PAVEMENTS AND FULL DEPTH RECYCLING OF FLEXIBLE PAVEMENTS Course Freeways and Arterials 2 Lane Highways Present AADT > 2000 Present AADT < 2000 Short Term Treatment (5 Years or less) Long Term Treatment Short Term Long Term Treatment Short Term Long Term Treatment Treatment Treatment (5 Years or (5 Years or less) less) Conventional Paving Recycling Conventional Paving Recycling Conventional Paving Recycling Surface 50 HL 1, 3 or 4 40 HL 1, 3 or >40-50 HL1,3 or 4 1. >40-50 HL1,3 or 4 1. > Binder 5. Nil Nil 0 or or Nil Nil Nil Levelling Nil Nil Nil Nil Nil Nil B

10 Padding Refer to 2. for all cases NOTES: >1. For surface course hot mix types, refer to PHY C-16. Use 25mm thickness when specifying open friction course on urban freeways. 2. Amount of padding dictated by: a. Performance. b. Cross section data. c. Extent of transverse and longitudinal corrections to give acceptable crossfall. 3. Thickness to be 20 mm average. 4. Normally HL2 is placed beneath the binder course, but occasionally this order may be reversed. If sandwiched between other hot mix layers it could result in wheel truck rutting at stop locations. 5. The need for a binder or levelling course will be determined at the design stage. >6. No recycled surface courses are permitted on highways with traffic greater than 5000 AADT/2 lanes. THICKNESS FOR RESURFACING AND PARTIAL DEPTH RECYCLING OF FLEXIBLE PAVEMENTS B