INDEX Warrant for Reclaiming Asphalt Pavement - Partial Depth Warrant for Reclaiming Asphalt Pavement - Full Depth

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1 INDEX GENERAL Tender Items Traffic Warrant Reference Publication Warrant for Reclaiming Asphalt Pavement - Partial Depth Warrant for Reclaiming Asphalt Pavement - Full Depth Reclaimed Material Contaminated Existing Pavement Design Alternatives Specifications Special Provisions Standard Drawings COMPUTATION Source of Information Method of Calculation Loss Allowance for Reclaimed Asphalt Pavement DOCUMENTATION Documentation Accuracy B

2 GENERAL Tender Items Traffic Warrant Reclaimed Asphalt Pavement (RAP): means removed asphaltic concrete material, consisting of aggregates and asphalt cement, which is processed for and used in asphaltic concrete. Reclaiming asphalt pavement to its full depth applies when the total thickness of asphalt pavement is to be removed and the material is re-used in recycled hot mix. Reclaiming asphalt pavement to a partial depth applies when the top portion of the asphalt pavement is to be removed by cold milling or cold planing and the material is re-used in recycled hot mix. The following items are associated with reclaiming asphalt pavement. Reclaim Asphalt Pavement - Full Depth. Reclaim Asphalt Pavement - Partial Depth Reclaim Asphalt Pavement, Full Depth over Concrete Non - PQP item Reclaim Asphalt Pavement - Partial Depth Reference Publication PQP item Reclaim Asphalt Pavement - Full Depth Reclaim Asphalt Pavement, Full Depth over Concrete Recycled Hot Mix may be used in any paving course except in surface courses carrying in excess of 5000 AADT/2 Lanes. 1. A comprehensive write-up on Hot Mix Recycling information is contained in the publication prepared by the MTO Pavement and Foundation Design Section entitled "TASK FORCE REPORT II ON HOT MIX RECYCLING", May Conventional hot mix paving is covered in this manual in Section B Hot Mix B

3 Warrants for Reclaiming Asphalt Pavement - Partial Depth (a) (b) Existing asphalt pavement depth of 65 mm or more which is not badly distorted or cracked. When a minimum thickness of 40 mm can be left in place Warrants for Reclaiming Asphalt Pavement - Full Depth (a) (b) (c) When deep cracks in the existing asphalt pavement are present which would reflect through the overlay. Broken pavement, heavy distortions and/or wheel rutting of the existing asphalt. Thin pavement which is badly distorted Surplus Reclaimed Material It is advisable to achieve a balance between the reclaimed asphalt pavement available and the recycled hot mix required. If surplus reclaimed material is available, then the following steps should be taken: a) Reduce the amount of reclaimed asphalt pavement. b) Stockpile the material for use on a future contract. (To be confirmed by Regional Geotechnical Section.) c) Excess amount to become the property of the contractor for use as recycled material elsewhere at this discretion. d) Milled or crushed material may be used as Granular 'A' for roadway construction, when the surplus amount is small and a proper placement area is available Contaminated Existing Pavement Design Alternatives Existing Asphalt waterproofing material from bridge decks is not to be included with the reclaimed material. This material is not acceptable for recycling. The following main design alternatives should be considered for any construction project requiring hot mix paving B

4 Specifications - Conventional paving; Special Provision - paving with conventional and/or recycled hot mix; - full depth removal and paving with conventional and/or recycled hot mix; - partial depth removal and paving with conventional and/or recycled hot mix; - any combination of the above Standard Drawings Reclaiming and recycling of asphalt pavement should be considered for all projects. It is preferable that salvageable asphalt pavement be utilized on that particular contract rather than stockpiling it for future work. The design alternative chosen should be the most economical or cost effective. There is no Ministry construction specification for these tender items. The work of reclaiming asphalt pavement is governed by special provision. The designer should refer to Chapter 'E' of this manual to review the applicable special provisions. Options regarding surplus material are noted on the special provisions. The average reclaiming depth for the tender item "Reclaiming Asphalt Pavement-Partial Depth" is to be recorded in the appropriate standard special provision. There are no Ministry standard drawings directly applicable to this type of work. Granular construction standard drawings in the 200 series should be referenced for roadway restoration B

5 COMPUTATION Source of Information Source of information for the above tender items are the Regional Geotechnical Section, Pavement Design Report, the original cross-section data, soil borings and asphalt pavement core logs Method of Calculation The quantity of partial depth reclaimed asphalt is initially calculated in cubic metres by establishing the volume to be removed. This volume is converted to tonnes. The conversion factor is determined by the Regional Geotechnical Section on a Project specific basis as this will vary depending on the composition of the existing asphalt pavement. The quantity of full depth reclaimed asphalt is calculated and documented in square metres. Where excavation is required in areas of full depth reclaiming of asphalt pavement, the volume of the reclaimed asphalt pavement overlying the excavation will be included in the excavation quantity for payment purposes Loss Allowance for Reclaimed Asphalt Pavement a) Partial Depth Reclaiming Projects A loss allowance factor of 10% should be included in the design calculations. This factor includes transportation, stockpile, moisture and hot mix production loss. e.g. Reclaimed Material Available for Recycling t 10% loss t Material to be Milled t b) Full Depth Reclaiming Projects No loss allowance factor is applied. Any volume losses due to transportation, stockpiling and hot mix production are assumed balanced by granular pickup during the full depth removal operation DOCUMENTATION Reclaiming asphalt pavement is identified on the removal drawings by using the pavement removal symbol B

6 Documentation of reclaimed asphalt pavement is complicated by requiring that some locations have full depth reclaiming or removal in square metres, whereas others have partial depth reclaiming by the tonne. It is important that the quantity sheets show sufficient detail by station to station and offset to clearly define the reclaiming and removal areas. This also applies to removal drawings, which should be labelled appropriately when the pavement removal symbol is used. When a portion of a roadway cross section requires reclaiming asphalt pavement, a typical section should be included in the contract drawings to identify the location and extent of reclaiming. The limits of reclaiming on side roads, entrances etc. must be specified on either the plan or the quantity sheet. Quantities for reclaiming Asphalt Pavement - Partial Depth are documented on the Quantities -1 or -2 sheet. The average reclaiming depth is documented on the applicable standard special provision. Quantities for Reclaiming Asphalt Pavement - Full Depth are documented on any miscellaneous Quantity Sheet. Existing asphalt pavement depths are usually available to the contractor through the soils information bore hole data. If these are not available the depth should be obtained from the Regional Geotechnical Section and the average depth documented on the quantity sheet. The station to station and location is specified on the quantity sheet. In complicated configurations the offsets are recorded. Quantities for each tender item are totalled. These totals are the tender totals and are transferred to the tender document Documentation Accuracy Quantity entries are recorded in whole numbers. Stations are recorded in whole number metres. Spot checking is required B