Common Airport Pavement Maintenance Practices (2011) / Chapter Skim
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Appendix B - Catalog of Airport Pavement Preservation Treatments
Appendix B - Catalog of Airport Pavement Preservation Treatments
Pages 53-102
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From page 53... ...
REPAIRS OF PCC PAVEMENT 88 FACT SHEET 18 -- FULL-DEPTH (PATCH) REPAIRS OF PCC PAVEMENTS 90 FACT SHEET 19 -- MACHINE PATCHING OF PCC PAVEMENT WITH AC MATERIAL 92 FACT SHEET 20 -- SLAB STABILIZATION AND SLABJACKING 94 FACT SHEET 21 -- LOAD TRANSFER RESTORATION 96 FACT SHEET 22 -- CRACK AND JOINT STITCHING 98 FACT SHEET 23 -- AC OVERLAYS OF PCC PAVEMENTS 100 FACT SHEET 24 -- BONDED PCC OVERLAY OF PCC PAVEMENTS 102 APPENDIX B Catalog of Airport Pavement Preservation Treatments
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From page 54... ...
Thirty-eight pavement preservation treatments were included on the survey form for respondents to review; these encompassed commonly used pavement preservation treatments for AC and PCC pavements. The 24 treatments included in the catalog were taken from the 50 responses and each of these has been used routinely by at least one of the airports surveyed, or they have been tried by at least 10% of the airports.
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From page 55... ...
Although the pavement preservation treatments are described separately, several treatments can be used on the same pavement section at the same time, or at different times, as part of a single pavement rehabilitation project or strategy. For example, a single PCC pavement rehabilitation project may include four maintenance and rehabilitation (M&R)
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From page 56... ...
It can be used to improve pavement friction by removing materials from the pavement surface, to clean pavement surface before the application of sealants, and to remove traffic control lines and signs. The best improvement in pavement surface friction by shot blasting is achieved when abrasion-resisting aggregate particles are embedded in a mortar that can be abraded by shot blasting.
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From page 57... ...
American Concrete Pavement Association, Diamond Grinding and Concrete Pavement Restoration, Report TB008P, Skokie, Ill., 2000. Purpose and Selection Criteria The purpose of diamond grinding is to improve pavement smoothness and/or improve pavement surface friction.
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From page 58... ...
Diamond grinding done only to improve pavement surface friction on relatively new pavements may not require resealing of joints. Grinding done to correct faulting on older pavements is typically followed up by joint resealing.
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From page 59... ...
Typical Service Life and Costs When used to protect the existing pavement structure as a preventive maintenance treatment, microsurfacing can prolong pavement life span by 4 to 6 years. When used to restore or improve pavement surface; for example, to restore pavement friction or to repair wheel track rutting, microsurfacing can last 5 to 8 years.
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From page 60... ...
For AC pavements, only one airport surveyed used microsurfacing routinely, and two airports surveyed have tried using it. For PCC pavements, only one of the surveyed airports indicated use of microsurfacing.
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From page 61... ...
Minnesota Department of Transportation, Preventive Maintenance Best Management Practices of Hot Mix Asphalt Pavements, Report MN/RC–2009-18, Office of Materials and Road Research, Maplewood, May 2009. Hicks, R.G., S.B.
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From page 62... ...
These cracks can be temporarily repaired by fine aggregate hot mix or liquefied patching materials similar to a slurry material. Airport Use Based on the survey, a majority of all airports routinely perform crack sealing using a hot-poured bituminous sealant.
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From page 63... ...
The patching with hot mix or cold mix can be used for both bituminous pavements and PCC pavements; however, permanent repairs of PCC pavements are typically done using PCC material. If pavers or graders are used, the treatment is called machine patching and is described on a separate Fact Sheet.
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From page 64... ...
A typical unit cost for small-area patching is $20 to $40 per square yard. Materials and Construction The main types of patching materials include hot mix, local or agency-specified cold mix, and proprietary cold mix.
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From page 65... ...
Purpose and Selection Criteria Spray patching is used to slow down pavement deterioration of vulnerable localized areas or to repair localized pavement distresses such as ravelling, flushing, and block cracking. A properly applied spray patching produces an all-weather surface that seals the pavement surface, prevents or retards propagation of surficial distresses, and can provide improved surface friction.
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However, the usage of manual spray patching has been declining. Only a few airports surveyed routinely use spray patching or have tried it.
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From page 67... ...
Typical Service Life and Costs Permanent repairs may last 5 to 12 years or more; semi-permanent repairs may last approximately 5 years or less. A typical cost of machine patching is $10 to $25 per square yard.
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Airport Experience About one-half of all survey respondents routinely use or have tried using machine patching. A large majority of respondents reported very good or good performance.
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From page 69... ...
The cost can range from $0.5 to $2 per square yard. Materials and Constructions Restorative seals designed to seal the pavement surface use slow or medium setting asphalt emulsion further diluted with water.
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From page 70... ...
71 correct application rates, and in some instances the use of sand, restorative seals can generally provide satisfactory levels of pavement friction. Airport Experience About one-half of the airports surveyed routinely use or have used restorative seals, and a large majority of the users reported very good or good performance.
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From page 71... ...
Fine milling, also called micromilling, removes unevenness from the pavement surface or improves its texture, and leaves an abraded surface that can be used as a driving surface. Sources of Information and Additional Resources Hicks, R.G., S.B.
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From page 72... ...
Materials and Construction Milling is a general term used to describe the removal of the surface of AC or PCC materials from pavements by a self-propelled unit having a cutting drum equipped with closely spaced carbide-tipped tools. Micromilling and precision-milling are types of milling that strive to provide a more even platform for an overlay and/or a finished pavement surface.
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From page 73... ...
When used to restore or improve pavement surface; for example, to restore pavement friction, surface treatment can last 5 to 8 years. The cost of a single surface treatment is approximately $2 to $4 per square yard.
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From page 74... ...
Newly constructed surface treatments need to be protected from traffic for several hours after construction. Emulsion application rates for seal coats typically range from 0.2 to 0.4 gallon per square yard depending on the existing surface (granular, seal coat, or AC)
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From page 75... ...
When used to restore or improve pavement surface characteristics, for example to restore pavement friction, slurry seals can last 3 to 7 years. The cost of slurry seal is approximately $2 to $4 per square yard, typically less than half of the cost of a hot-mix overlay.
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From page 76... ...
Cooler temperatures and wetter conditions can result in long curing times during which the slurry seal can be damaged by traffic. Airport Experience A small number of surveyed airports reported the use of slurry seals routinely, or have tried using them.
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From page 77... ...
Overlays are also used as a preventive maintenance treatment to seal pavement surfaces from intrusion of water, slow surface ravelling, seal small cracks, and improve surface friction. Overlays can be used to strengthen the pavement structure to accommodate increased pavement loads.
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From page 78... ...
Airport Experience A majority of surveyed airports routinely use or have tried using hot-mix overlays with or without prior milling, and nearly all surveyed airports reported very good or good performance. No responding airports reported using thin overlay (with thickness of less than 11⁄2 in.)
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From page 79... ...
Rubber-tired rollers 3. Static dual steel drum rollers Re-former MixingLeveling and profiling Scarifying Hot mix for integral overly Optional addition of aggregate and/or beneficiating hot mix Infrared heaters Second screed Adding rejuvenator 80
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From page 80... ...
HIR is typically carried out only during the warmer, dryer months. Cooler temperatures and wetter conditions can result in longer heating times leading to the overheating and burning of the pavement surface, and creating smoke and vapors.
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From page 81... ...
Typical Service Life and Costs CIR with an appropriate hot-mix overlay provides a service life of 10 years or more. In situations where the surface layer atop the CIR mix is a surface treatment, the expected service life is lower.
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From page 82... ...
83 fied asphalt is typically carried out only during the warmer, dryer months. Cooler temperatures and wetter conditions can result in long curing time during which the cold mix is susceptible to moisture intrusion and abrasion by traffic.
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Typical Service Life and Costs Preliminary results suggest life spans of 10 years or more. The typical cost of a UTW is estimated to be in the range of $12 to $18 per square yard.
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From page 84... ...
Joints are not sealed. Airport Experience Only a few surveyed airports reported routine use of whitetopping.
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Typical Service Life and Costs There are three main categories of sealants for PCC pavements on the market: hot-poured bituminous sealants, silicone sealants, and compression seals (preformed or neoprene)
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From page 86... ...
to force the sealant into a full contact with the joint sidewalls and to produce the correct shape of the sealant on top. Airport Experience A majority of surveyed airports reported routine use of silicone sealants, half of the responding airports have used bituminous sealants, and a minority of responding airports has used neoprene sealants.
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From page 87... ...
Typical Service Life and Costs A partial-depth repair can last as long as the slab itself, typically 10 years or more. A typical cost of a partial-depth repair operation is in the range of $160 to $220 per square yard.
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From page 88... ...
Airport Experience About one-half of the airports surveyed routinely used or have tried partial-depth repairs with PCC material, a majority of surveyed airports have used AC material, and a large minority of surveyed airports has used proprietary materials. Overall, the performance of PCC materials was reported to be better than the performance of AC or proprietary materials.
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From page 89... ...
Full-depth repairs are often done together with other maintenance treatments, such as partial-depth repairs, load transfer restoration, and crack and joint sealing, as part of a pavement rehabilitation project. Full-depth repairs using PCC are also done before overlays.
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From page 90... ...
The restoration of the load transfer is accomplished by installing the dowels before or after the slab placement. Airport Experience A majority of surveyed airports routinely used or have tried full-depth repairs using PCC or AC materials.
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From page 91... ...
A typical cost of machine patching repairs is in the range of $10 to $30 per square yard. Materials and Construction Typically, permanent machine patching includes the following steps: • Removal of the deteriorated PCC material by milling or chipping.
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From page 92... ...
93 Airport Experience A few surveyed airports reported on the use of machine patching of PCC pavements with AC routinely; other surveyed airports reported that they have tried it. Performance data from the survey are incomplete.
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Typical Service Life and Costs The expected service life of slab stabilization and slabjacking is 5 to 10 years. The typical cost of slab stabilization is in the range of $80 to $180 per square yard.
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From page 94... ...
After all holes are injected, the temporary plugs are removed and the holes are filled flush with cement grout. Verification testing -- After a minimum of 24 h, slabs are retested for the presence of voids and load transfer efficiency.
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Typical Service Life and Costs The estimated service life for load transfer restoration is between 5 and 15 years. The typical cost of a load transfer restoration or crack stitching is on the order of $50 to $100 per dowel bar or tie bar.
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From page 96... ...
Insertion of dowels -- The most common type of load transfer device is a smooth epoxy-coated dowel bar. The size of the dowel bars depends on the slab thickness and anticipated loads.
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From page 97... ...
A typical cost of crack stitching is in the order of $60 to $120 per dowel bar or tie bar. Stitching of Cracks and Joints Stitching of cracks using slot stitching is very similar to load transfer restoration with the following main exceptions: • Stitching is done to repair longitudinal and meandering cracks, nonworking transverse cracks, and longitudinal joints.
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From page 98... ...
99 Deformed tie bars inserted and grouted into drilled holes (diameter is typically ¾ inch) Dowel barPCC Slab Base 35º – 45º Longitudinal Crack Cross sectional view Longitudinal Crack Plan view Drill hole @ 24 inches FIGURE B16 Stitched longitudinal crack.
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From page 99... ...
Considering that a typical cost of hot mix is $60 to $90 per ton, a 4-in.-thick overlay will cost $12 to $18 per square yard. However, this cost does not include any rehabilitation of the underlying PCC pavement that may be required before placing the overlay.
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From page 100... ...
Pre-overlay repairs -- Repairs include slab repairs (slab stabilization, load transfer restoration, full-depth repairs) and improving drainage (retrofit subdrains)
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From page 101... ...
Hall, "Design, Construction, and Performance Monitoring of Ultra-Thin Whitetopping at a General Aviation Airport," Proceedings of the 27th International Air Transportation Conference, Advancing Airfield Pavements, American Society of Civil Engineers, Reston, Va., 2007. Purpose and Selection Criteria The purpose of the bonded PCC overlay is to improve pavement smoothness and pavement surface friction and to provide increased structural strength of the pavement.
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From page 102... ...
. Airport Experience A few surveyed airports reported the use of bonded overlays routinely or have tried them.
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