Special Provision No. 399F01 December 2014

Transcription

1 FULL DEPTH CRACK REPAIRS Item No. Special Provision No. 399F01 December SCOPE This Special Provision covers the requirements for full depth crack repairs in asphaltic concrete pavements. 2.0 REFERENCES This Special Provision refers to the following standards, specifications or publications. Ontario Provincial Standard Specification, Construction OPSS 308 OPSS 313 OPSS 501 Tack Coat Hot Mix Asphalt - End Result Compacting Ontario Provincial Standard Specification, Material OPSS 1151 Superpave and Stone Mastic Asphalt Mixes 3.0 DEFINITIONS For the purpose of this Special Provision, the definitions in OPSS 313 and the following definition apply: Crack Repair means the portion of any crack that has been repaired to the base of the asphaltic concrete layer during any given stage of construction under this Contract. 4.0 DESIGN AND SUBMISSION REQUIREMENTS Not Used 5.0 MATERIALS 5.01 Hot Mix Asphalt Hot mix asphalt shall be according to OPSS Tack Coat Tack coat shall be according to OPSS EQUIPMENT Not Used 7.0 CONSTRUCTION Cracks requiring repair are included in the Contract Documents and shall be identified by the Contract Administrator on site. Repairs shall be completed on all single and multiple cracks identified for repair. All crack repairs shall be completed prior to any binder and surface course paving required by the Contract. December 2014 Page 1 of 5 SSP 399F01

2 Crack repairs shall be completed prior to shutdown the same day the existing HMA is removed full depth Asphalt Removal and Foundation Preparation The existing HMA shall be removed full depth, to a width of 1.0 m centered over the crack. All four sides of the asphalt removal area shall have a vertical face. Protrusions greater than 5 mm on the sides and 10 mm on the bottom of the HMA removal area shall not be permitted. Granular base materials disturbed by the removal operations shall be shaped to the proper cross-fall and recompacted according to OPSS 501 prior to the placement of HMA. All vertical faces of the existing HMA shall be cleaned and dried prior to applying tack coat. All loose debris shall be completely removed from the adjacent roadway before placing the HMA. Tack coat shall be applied to vertical surfaces according to OPSS 308 prior to placing HMA Placing Hot Mix Asphalt Paving shall not be carried out if the Roadbed is frozen. When placing HMA on a granular grade, the granular grade shall not be saturated and shall be free of standing water. The surface of a pavement upon which HMA is to be placed shall be clean and dry at the time of HMA placement. A course of HMA shall not be placed upon a previously laid course until the surface temperature of that previous course is 50 C or less. HMA shall not be placed unless the ambient air temperature is at least 2 C. HMA shall not be placed faster than it can be properly raked. The HMA shall be placed in uniform lifts between [* Designer Fill-in, See Notes to Designer] mm and [** Designer Fill-in, See Notes to Designer] mm in thickness. The total HMA thickness placed shall be [*** Designer Fill-in, See Notes to Designer]. All lifts shall be compacted to a minimum of 91.5% of the maximum relative density using appropriate rollers to provide a uniformly compacted mat. Prior to roller compaction, defects in the HMA placed shall be corrected. After final compaction of each course, the surface shall be smooth and true to the established crown and Grade, uniform in texture and shall be free of any defects including, but not limited to, segregation, flushing, oil spills, and roller marks. Where the HMA cannot be adequately compacted by the roller, it shall be compacted using mechanical selfpowered gas-, electric-, or air-powered tamping equipment. The compacted surface of the HMA shall be flush with the adjacent pavement surface Sampling Core sampling, in duplicate, is required at repaired locations where identified by the Contract Administrator. For transverse cracks, number of duplicate samples will not exceed one per every 20 transverse cracks. For longitudinal cracks, number of duplicate samples will not exceed one per every 100 m length of the December 2014 Page 2 of 5 SSP 399F01

3 longitudinal cracks. The above limits may be exceeded only when rejectable samples are encountered, in which case further samples may be required by the Contract Administrator to define the extent of the rejectable area. Core samples shall be obtained, in duplicate, in the presence of the Contract Administrator, no later than the next Working Day after receiving the Contract Administrator s written notice of the sample locations. Each core shall have a minimum nominal diameter of 150 mm and a maximum nominal diameter of 200 mm and shall extend to the full depth of the crack repair. Care shall be taken to ensure that cores are not damaged during coring operations or in transit. If a core is damaged, a replacement core shall be extracted immediately at a location adjacent to the original core. All cores shall be handled, labeled, and delivered according to the requirements specified in the Contract Documents. One core from each duplicate set shall be tested by the QA laboratory. The other sample shall be designated as referee sample. HMA and compaction requirements for filling the sample holes shall be the same as the adjacent pavement surface. Sample holes shall be cleaned, dried, and filled and then compacted using a mechanical self-powered gas-, electric-, or air-powered compactor immediately after sampling Management of Excess Material Management of excess material shall be according to the Contract Documents. 8.0 QUALITY ASSURANCE Acceptance of the crack repairs shall be based on quality assurance measurements of the following criteria: a) Core compaction and verification of a full depth repair; b) Surface tolerance; and c) Surface appearance Core Compaction and Verification of a Full Depth Repair The Contractor shall provide full depth core samples, if requested by the Contract Administrator, which shall be used to determine the asphalt compaction of each lift of HMA. Acceptance for core compaction shall be based on the HMA meeting a minimum compaction of 91.5% at any individual sampling location, determined using LS 262 (Notes 1 and 3). All core samples shall be visually inspected by the Contract Administrator to ensure a full depth repair has been carried out Surface Tolerance Prior to paving over the completed crack repair, the surface of the crack repair shall be flush with the adjacent pavement, true to line and grade and free of rutting. When tested with a 3 m straightedge placed anywhere in December 2014 Page 3 of 5 SSP 399F01

4 any direction on the surface, except across the crown or drainage gutters, there shall not be a gap greater than 6 mm between the bottom of the straightedge and the surface of the pavement. All areas not meeting the surface tolerance requirements shall be repaired and re-evaluated according to the Repairing and Re-evaluating subsection Surface Appearance HMA deemed by visual appearance to have segregation, flushing, oil spills, and roller marks, but not limited to these, shall be considered deficient material or work. Deficient material or work shall be repaired and re-evaluated according to the Repairing and Re-evaluating subsection Repairing and Re-evaluating Full depth crack repairs that fail to meet the Contract requirements shall be deemed rejectable and warrant repairs as follows: a) Repairs for deficient compaction shall be by removal and replacement of the deficient lift(s), including the lift(s) above the deficient lift. b) Repairs for deficient repair depth shall be by full depth removal and replacement. c) For a rejectable transverse crack repair, full length of the crack repair in the traffic direction where the rejectable core was taken shall be repaired. d) For a rejectable core within a longitudinal crack repair, minimum length of the repair shall be 10 m centred over the core location. e) Repairs for surface tolerance and/or surface appearance shall be by: i) milling and paving the top lift of the repair; or ii) grinding (by milling, micro milling or diamond grinding). If a core sample obtained in any crack repair is found to be rejectable for any reason, the Contract Administrator may require that the Contractor core any adjacent crack repairs, to more fully define the extent of the rejectable area. Rejectable crack repairs shall be repaired as specified in this Special Provision. Repaired areas shall be re-evaluated for acceptance according to the Quality Assurance section Referee Testing The Contractor may invoke referee testing by submitting a written request to the Contract Administrator within 3 Business Days following notification from the Contract Administrator that the compaction result has been rejected. Referee labs will be selected from a roster of labs maintained by the Owner for that purpose. The referee test result shall be binding on both the Contractor and the Owner. December 2014 Page 4 of 5 SSP 399F01

5 9.0 MEASUREMENT FOR PAYMENT 9.01 Actual Measurement Measurement of full depth crack repairs shall be by length in metres to the nearest decimeter, along the total length of all crack repairs completed Plan Quantity Measurement When measurement is by Plan Quantity, such measurement shall be based on the units shown in the clauses under Actual Measurement BASIS OF PAYMENT Full Depth Crack Repairs - Item Payment at the Contract price for the above tender item shall be full compensation for all labour, Equipment and Materials required to do the Work, except that the hot mix material shall be paid for under the appropriate hot mix tender item. Repairs of any rejectable crack repair, including any associated traffic control shall be carried out at no cost to the Owner Referee Testing for Compaction Payment for referee testing, including cost of sample delivery, shall be the responsibility of the Owner provided the referee compaction test result(s) for all lifts in each core sample meet or exceed 91.5%; otherwise, the Contractor shall be responsible for the cost of referee testing and sample delivery. The cost of the referee testing shall be based on the referee testing rates as specified elsewhere in the Contract Documents, multiplied by the number of lifts in the core. December 2014 Page 5 of 5 SSP 399F01