304 - SURFACE TREATMENTS - OPSS 304

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1 04 - S - OPSS GENERAL For economic reasons, roadways having low traffic volumes will often be selected for double surface treatment or prime and surface treatment in place of Hot Mix paving. Primed and surface treated roads are not as strong structurally as hot mix pavements. The decision to use surface treatment is not based entirely on traffic AADT, but on many factors such as axle loading, surface type continuity, etc. This work is carried out either as a separate contract or under the grading contract by means of tender items or funds provided under Services (Sundry Construction). See Chapter "D" of this manual. The preferred length of projects for surface treatment is 10 km or greater. A follow-up surface treatment application of treated roads may take place several years after the surface treatment has been applied Types of Surface s The following applications are available depending on traffic volumes, status of road and type of road surface. a) Single Surface. This type of surface treatment is to be applied to either a primed road, a roadway with a previous applied surface treatment or a paved roadway. The work consists of a single application of binder followed by a single application of Class 1,, 4, or 6 aggregate. See table on page B04-6 for application rates. b) Double Surface Double surface treatment is to be applied to either a granular base or a primed road. The work consists of: (a) Two alternate applications of binder and Class aggregate (placed over granular base). See application rates on page B04-6. or 05 0 B04-1

2 (b) An application of binder and Class 1,, 4, or 6 aggregate followed by an application of binder and Class 1,, 4, or 6 aggregate (placed over primed road.) See application rates on page B04-6. Class and 5 Aggregates are generally only used by Municipalities Restoring Roadway Surfaces A tender item for restoring a roadway surface may be required depending on the time elapsed between grading and the priming operation. Refer to Section B-01 of this manual for detail estimating and documentation on Restoring Roadway Surface Stockpiling of Aggregates Tender Items For economic reasons in areas where commercial aggregates are not readily available, the aggregate material required for Surface may be stockpiled under a grading contract. The stockpiling of this material is to be paid for under the appropriate tender item. Special Provisions listed in Chapter "E" of this Manual (Materials to be Stockpiled) should be completed indicating the quantity, type of material and location of the stockpile. An allowance of 10% should be added when calculating the required amount of stockpiled aggregates. The tender items associated with the application of surface treatments are: a) Single Surface, specify only one type of Aggregate. - Binder - Class 1 Aggregate - Class Aggregate - Class 4 Aggregate - Class 6 Aggregate - Traffic Convoy b) Double Surface, - Binder - Class 1 Aggregate - Class Aggregate 05 0 B04-

3 - Class 4 Aggregate - Class 6 Aggregate - Traffic Convoy Specifications When required, these item descriptions may be expanded to include - "Stockpiled", or - "from Stockpile". A non-standard Special Provision must be written against these items to designate "Stockpiled" or "From Stockpile". Information regarding surface treatments is contained in OPSS Special Provisions The designer should refer to chapter `E' of this manual to review the applicable Special Provisions. A non-standard special provision is required to identify: - the locations of the work when several highways are to be surface treated; - the length and width of the roadway; - the amount of Binder; - the amount and type of Aggregate to be used at individual locations; - location of stockpile and length of haul. The Contractor is required to supply the binder. When the Contractor must use Ministry supplied aggregate "from Stockpile", complete the general standard special provision "Schedule of Materials to be Supplied by the Owner" and identify the Class of aggregate supplied by the Ministry and required on the contract Standard Drawings The designer must base his work on Ontario Provincial Standard Drawings. Cross section elements are illustrated in the 00 series. 04. COMPUTATION Source of Information Recommendations from the Regional Geotechnical Section, Regional/Area Offices and Regional Quality Assurance Section are the main source of information for these 05 0 B04-

4 tender items. Traffic Convoy information may be obtained from the Regional Traffic Office Method of Calculation a) Class 1, Class, Class 4, Class 6 Aggregate The unit for these tender items is tonne (t). When a weigh scale is not available (such as on multi highway surface treatment contracts), the unit for these tender items is cubic metre (m ). Quantities are estimated on the recommended theoretical pavement width (plus 0. m on the inside of curves) times the length of the roadway. The application rates are shown on page B The density is.0 t/m for Class and Class 4 aggregate. The density is.6 t/m -.0 t/m for Class 6 aggregate. Allowance (10%) should be made for loss due to stockpiling. b) Traffic Convoy The tender unit is by the hour. The number of hours required is to be determined in consultation with the Regional Traffic Office. 04. DOCUMENTATION Contract drawings and quantity sheets are not required with the above tender items. Tender quantities for individual tender items are transferred from the calculation sheet to the Tender Document Documentation Accuracy Calculated quantities in kilogram, tonnes and cubic metre are recorded to the nearest whole number, and by the hour for the Traffic Convoy item. Stations are recorded in whole number metres APPLICATION RATES The specified rate application for the binder, the class of aggregate, and the specified application rate for the aggregate are determined by the Regional Geotechnical Section, Quality Assurance and/or Area Offices B04-4

5 PRIME AND APPLICATION RATES Aggregate Type Primer or Binder (5) Aggregate Grade Range, kg/m Typical, Class Range, kg/m kg/m Typical, kg/m Prime Class 4 Primer 1.90+/ Single Surface Class 1 Class (1) (6) Class 4 () Class 5 Class 6 CRS- or RS- HF-150S CRS-,HF-150S CRS- or RS- HFMS-(ON) or HFMS-P(ON) Double Surface Class (6) Class & 1 HF-150S () HF-150S (4) CRS-,RS- () CRS-,RS- (4) Class & 4 CRS-,RS-() CRS-,RS-(4) Class & 5 CRS-,RS- () CRS-,RS- (4) Class & 6 HFMS-P(ON) () HFMS-P(ON) (4) Notes: (1) Class surface treatment may cause dust problems in urban areas. () Do not apply to flushed surface treatments, flushed pavements or where low friction values are a concern. () Initial application. (4) Second application. (5) Decrease binder rates towards the lower limit of the range when there is heavy commercial traffic. (6) The use of Granular "A" aggregate in a Single or Double Surface is not recommended B04-5