PAVEMENT PREVENTIVE MAINTENANCE PROGRAM GUIDELINES May 1, 2001 The Office of Pavement Engineering
Table of Contents Cover Sheet Page 1 Table of Contents Page 2 Program Purpose Page 3 References Page 3 Definitions Page 3 Program Development Page 4 Project Selection Guidelines Page 4 Available Treatments Page 4 Pavement Preventive Maintenance Summary Table Page 5 Crack Sealing Page 6 Chip Sealing Page 10 Micro-Surfacing Page 13 Polymer Modified Asphalt Concrete Page 17 Thin Hot Mix Overlays Page 19 Concrete Pavement Restoration Page 21 Drainage Preservation Page 23 Appendix of GQL Logic for Candidate Selection Page 25
ODOT Pavement Preventive Maintenance Guidelines Purpose Preventive Ma intenance ( PM) is a pla nned strategy of c ost e ffective tr eatments to a n e xisting roadway system and its appurtenances that preserves the sy stem, retards future deterioration, extends the service life, and maintains or improves the functional con dition of the sy stem without substantially increasing structural capacity. Pavement PM treatments reduce the amount of water infiltrating the pavement structure, protect the pavement system, slow the rate of deterioration, or correct surface deficiencies such as roughness and non-load related distress. These treatments contribute little or no improvement to the pavement structure. They are not applicable and should never be applied if fatigue-related distress exists in the pavement. References Pavement Design and Rehabilitation Manual - January 1999 Pavement Condition Rating Manual - May 1999 Pavement Design and Selection Process - Policy Number 515-002 (P) - June 1999 Definitions Reactive Maintenance - Activities undertaken to correct defects and extend the life of the pavement until such a time that a proper rehabilitation or reconstruction project may be undertaken. Reactive maintenance is frequently performed on a failing pavement. It is a stop gap measure that keeps the road at an acceptable serviceability, and is seldom cost-effective. Minor Rehabilitation - W orked performed on a pavement intended to restore functional characteristics and protect the structural integrity. Major Rehabilitation - Worked performed on a pavement intended to restore structural integrity and functional characteristics. Pavement Preservation - The sum of all activities undertaken to provide and maintain serviceable roadways; this inc ludes Reactive a nd Pr eventive Ma intenance a s we ll a s Minor a nd Ma jor Rehabilitation.
Page 4 Program Development The intent of the pavement PM prog ram is to select, desig n, and construct PM treatments in an expedited fashion to extend pavement life and maintain the pavement surface at the highest possible level of serviceability. The Pavement Manag ement System (PMS) can be accessed by General Query Language (GQL) which can be used to provide a first cut list of candidate projects for all of the PM treatments. The logic used to construct this queryis found in the appendix of this document. Although local governments do not use the ODOT PMS, the logic used for this query, in conjunction with ODOT s Pavement Condition Rating (PCR) manual could be used to determine the applicability of the various treatments for local pavements. Furthermore, ODOT District Offices should put together a list of preventive maintenance candidates for the Urban PavingProgram on an annual basis and share this listing with each municipality in their District. The District Pavement Review Team should further evaluate the candidate projects with respect to PCR, Ride Number, Structural Deduct, and the pavement history to arrive at an optimal District PM program. Although warranty specifications ex ist for many of the preventive maintenance treatments, they should not be employ ed with pavements which do not qualify for preventive maintenance. Furthermore, it is imperative to remember t hat existing pavements under warranty should not be treated with PM b efore the warranty period is up. The intent of the warranty is to provide a maintenance free pavement. Project Selection Guidelines Pavement p reservation s trategies s hould be d eveloped t o i ncorporate b oth P M a nd p avement rehabilitation work at appropriate intervals to preserve pavement condition throughout its service life. Proposed pr ojects on the Multi- Lane D ivided a nd N ational H ighway Sy stem should be reviewed by the Pavement Review Team as described in the ODOT Pavement Policy. The review will determine the merits of the proposed project and th at highway safety has been or will be addressed. It is possible that proposed PM projects may be eliminated if they become too complex as a result of the need to increase capacity, improve traffic operations, or address safety betterments. Other projects meeting the established criteria may be substituted for eliminated projects in order to maintain a balanced program and provide for planned expenditures. Available PM Treatments Crack Sealing Chip Seals Micro-surfacing Polymer Modified Asphalt Concrete Thin Hot Mix Overlays Concrete Pavement Restoration (CPR) Drainage Preservation
Page 5 PREVENTIVE MAINTENANCE SUMMARY TABLE Pavement Applications Pavement Surface Crack Sealing Chip Seal Micro- Surfacing Polymer Modified Asphalt Concrete Thin Hot Mix Overlay Concrete Pavement Restoration Drainage Preservation Concrete / / / Asphalt / / / / / / Reasons For Friction / / / / Rideability / / / / Raveling / / / / / Rutting / / / Cracking / / / / / Oxidation / / / / Water / / / / / / Low Volume (<2500 ADT) X X X X X X X Traffic High Volume (>2500 ADT) X X X X X X Maximum Speed < 45 MPH Type A Average Cost Weight / Area Lane Mile (not incl. Shoulders) $.60 - $1.00 Per Lb. $1,000 - $4,000 $1.00 - $1.75 Per S.Y. $8,000 - $12,000 $1.25 - $2.00 Per S.Y. $8,000 - $16,000 $2.00 - $4.00 Per S.Y. $14,000 - $25,000 $2.50 - $3.50 Per S.Y. $17,000 - $25,000 $4.00 - $12.00 Per S.Y. $25,000 - $75,000 $2,000 - $5,000 Average Life (years) 1-4 5-8 5-8 7-12 8-12 7-12 1-5
Page 6 Crack Sealing - Flexible, Composite and Rigid Pavements Description & Purpose: Crack Sealing is the placement of a mixture of a neat or modified binder, such as a PG64-22, mixed with polyester or polypropylene fibers, into existing cracks in the pavement. Crack Sealing is used to minimize the intrusion of water into the pavement. By keeping water out of the pavement, erosion of the mix is kept to a minimum, deterioration of the crack is slowed, and less water is available to saturate the base materials. Pavement Condition Considerations: Flexible and Composite Pavements: There is a wide w indow of opportunity for cost effective crack seal ing of asphal t surfaced pavem ents. The i ntent of t he P MS GQL query i s t o sel ect pavements which have sufficient cracking for crack sealing mobilization to be worthwhile, yet preclude excessively cracked pavements. In general, cracks which display significant raveling of the crack face and secondary branch cracking (see photo) need more than just a crack seal and should be considered for some other type of preventive maintenance which may include crack sealing. Furthermore, pavements which require the use of crack sealing material in excess of 5000 lbs. per lane mile are questionable candidates for crack sealing. Where crack sealing is not asuitable method of preventive maintenance, other forms of pavement preservation should be considered. Rigid Pavements: There is not a GQL query for rigid pavements, as there are only a very small percentage of rigid pavements in the state, and these pavements are not ex pected to have cracks wider than hairline. Crack sealinghairline cracks in a rigid pavement has not been shown to be cost effective, and will result in a noisi er and rougher riding pavement. Where cracks are found to be wider than 1/8 inch and less than 1/4 inch, crack sealing may be beneficial; however, further investigation is recommended, as more serious problems may be present. Raveling of the crack face and secondary branch cracking in composite pavement. Hairline crack in rigid pavement.
Page 7 Traffic Constraints: Crack Sealing is suitable for all traffic levels. Design Considerations: Crack sealing may be done by ODOT forces, Contractual force account, or by standard contract work. For contract work, Supplemental Specification 825 (SS 825) ontains c the following Pay Items: 825 Pound (kilogram) Crack sealing, Type I 825 Pound (kilogram) Crack sealing with routing, Type I 825 Pound (kilogram) Crack sealing with sawing, Type I 825 Pound (kilogram) Joint sealing between rigid pavement and flexible shoulders, Type I 825 Pound (kilogram) Crack sealing, Type II 825 Pound (kilogram) Crack sealing, Type III 825 Pound (kilogram) Crack sealing, Type II or III 825 Pound (kilogram) Crack sealing, Type IV The different Type crack seal descriptions refer to differences in material, equipment, mixing, and application of the sealant. The speci fication also describes the different crack di mensions and appropriate sealant reservoir. Choosing the proper crack seal material type is a very important issue. Type I and Type IV materials are not appropriate for pavements which will be micro-surfaced within 2 years. The option of routingcracks prior to crack sealingis also provided for the Type I Crack Seal. However, routing should only be considered for pavements which are not expected to be treated for several years and where cracks are newly formed. Type II and Type III materials should be specified for preparing pavements just prior to micro-surfacing or chip sealing, but should be aged at least 6 months if applied prior to any type of Hot Mix Overlay or a Polymer Modified Asphalt Concrete. For quantity estimation, the following table is provided. The table is based on a unit of weight of the material of 63 pounds per cubic foot, and does not account for waste or spillage. This table is applicable for any of the pay item descriptions in SS 825.
Page 8 RUBBER-ASPHALT JOINT SEALING COMPOUND QUANTITY TABLE Pounds Required Per 100 Linear Feet Depth, Inches Width of Opening, inches 1/4 3/8 1/2 5/8 3/4 7/8 1 3/4 8.3 12.4 16.5 20.6 24.8 28.9 33.0 7/8 9.6 14.4 19.3 25.0 28.9 33.7 38.5 1 11.0 16.5 22 27.5 33.0 38.5 44.0 1-1/8 12.4 18.6 22.8 31.0 37.2 43.3 49.5 1-1/4 13.8 20.7 27.5 34.4 41.3 48.1 55.0 1-3/8 15.2 23.8 30.3 37.8 45.4 52.9 60.5 1-1/2 16.5 24.8 33.0 41.3 49.5 57.8 66.0 1-5/8 17.9 26.8 35.8 44.7 53.6 63.5 72.5 1-3/4 19.3 28.9 38.5 48.1 57.8 67.4 77.0 1-7/8 20.6 30.9 41.3 52.5 61.9 73.2 82.5 2 22.0 33 44.0 55.0 66.0 77.0 88.0 Traffic Control/Releasing Traffic: Maintenance of traffic is required to apply the sealant and allow it to cure. Cure time is usually less than 1 hour. Seasonal Construction Limitations: Crack Sealing operations are most effective when pavem ent temperatures are cool to cold. As pavements cool they contract, and thus widen the cracks allowing more sealant to en ter the pavement. Crack sealing should not be done on wet or damp pavements and should be applied on pavements when both surface temperature and ambient air temperature are above 40 degrees F. Anticipated Performance and Service Life: Crack Sealing will have little effect on current pavement condition. The intent of crack sealing is to slow the rate of deterioration and prolong the pavements life. Crack sealants are expected to last 2 to 3 years before re-application is necessary.
Page 9 Specification References: Supplemental Specification 825 Supplemental Specification 801 (see CPR) Unit Cost for Estimating: $0.60 to $1.00 per pound, ~$1,000 to $4,000 per lane mile, depending on the severity and extent of the cracking. For More Information Contact: David Powers, Office of Materials Management, 614-275-1387 Bill Christensen, Office of Highway Management, 614-644-6634 Aric Morse, Office of Pavement Engineering, 614-995-5994
Page 10 Chip Seal - Flexible and Composite Pavements Description & Purpose: Chip Seal is a sprayed application of a polymer-modified asphalt binder covered immediately by a washed limestone or dolomite aggregate, and rolled with a pneumatic roller. The binder is applied by an approved bituminous distributer, and the agregate placed by an approved aggregate spreader. The rolling operation is intended to seat the agregate into the binder and insure chip retention. Chip seals can be placed as single or double applications, depending on pavement condition. However, the conditions that warrant a double chip seal will not generally fall into a preventive maintenance category, and are not included in the PM guidelines. Chip seal is intended for low volume roadways to provide a new wearing surface as well as to eliminate raveling, retard oxidation, reduce the intrusion of water, improve surface friction and seal cracks. Pavement Condition Considerations: The intent of the PMS GQL query is to select low volume two lane roadway pavements which are structurally sound and are suitable for preventive maintenance. I n the process of selecting these pavements, the PMS GQL query will choose some pavements which exhibit distresses beyond the severity practical for a chip seal. The majority of these pavements can be acceptable candidates, provided some repairs are made prior to the chip seal. The following conditions should be given careful consideration by the pavement review team: Localized wheel track cracking should be repaired full depth with Item 253. Any potholes must be repaired full depth with Item 255 for composite pavements, and Item 253 for flexible pavements. Areas which exhibit de-bonding must be patched in accordance with Item 251. All existing patches must be in good repair prior to chip sealing. All existing cracks must be crack sealed prior to chip sealing (see Design Considerations) Localized areas which exhibit high severity longitudinal joint cracking should be patched with Item 253. Localized medium or high severity edge cracking must be repaired full depth with Item 253 prior to a chip seal. Localized edge cracking must be repaired with Item 253, prior to a successful chip seal.
Page 11 Rutting must be less than 1/8 inch in depth, and the rutting must have reached its maximum depth (i.e.: non-plastic). Where rutting is evident, reference should made to the High Stress Guidelines - Appendix B of the Pavement Design & Rehabilitation Manual. Traffic Constraints: Chip seal applications are intended to be used on two-lane low volume roadways with traffic levels below 2,500 Average Daily Traffic (ADT) and 250 Average Daily Truck Traffic (ADTT). W here frequent stopping and turning of truck traffic is expected, chip seal is not recommended. Design Considerations: Chip Seals are intended to provide a new wearing surface on pavements which have low volume traffic, at a lower cost than traditional methods. The pay item descriptions and their intended use follows: Item 82 1 Single chip seal with poly mer binder is to be specified in all non-warranty applications assuming the pavement is in an acceptable condition, as detailed above. Item 882 Single chip seal with warranty is specified the same as Item 821 Single chip seal above where the specifier wants warranty application. Non-warranty chip seal contracts must make provisions for removal of thermopla markings. stic pavement Neither warranty nor non-warranty specifications for chip seal include the removal and replacement of raised pavement markers. The contract should provide the contractor PayItem 202 and Item 621 for this purpose. Crack sealing should always be done in conjunction with a chip seal. Item 825 Type II or Type III crack sealing is compatible with chip sealing. Best practice is to lump both crack sealing and chip sealing into the same project. Otherwise crack sealing, Item 825 Type II or Type III, should be done within 6 months of a chip seal. Traffic Control/Releasing Traffic: Traffic should be restricted and speeds reduced to minimiz e the loss of chips from the pavement surface. Length of time for traffic restrictions depends largely on ambient weather conditions at the time of construction of the chip seal. Seasonal Construction Limitations: The construction season for this work is relatively short. Chip seals should not be placed in cool weather. I t usually requires about one month of warm weather followi ng construction for the aggregate particles to become reoriented and properly embedded in the asphalt membrane. The specifications require the chip seal to be placed between May 1 and Sept 1.
Page 12 Anticipated Performance and Service Life: Traffic and tire noise will increase as the result of a chip seal. A newly chip sealed pavement will have a PCR of ~100 initially. The condition of the pavement prior to the chip seal will influence the degradation of the PCR following the chip seal more t han any other factor. Althoug h no data currently exists concerning PCR trends of chip sealed pavements, the expected service life is 5-7 years, and the rate of PCR drop should be similar to that observed since the last hot mix overlay. Specification References: Supplemental Specifications 821 and 882 Unit Cost for Estimating: $1.00-$1.75sy, ~ $7,500/lane-mile for a single application. For More Information Contact: Dave Powers, Office of Materials Management, 614-275-1387 Bill Christensen, Office of Highway Management, 614-644-6634 Aric Morse, Office of Pavement Engineering, 614-995-5994
Page 13 Micro-Surfacing - Flexible and Composite Pavements Description & Purpose: Micro-surfacing i s a t hin surface, col d appl ied pavi ng m ixture com posed of polymer-modified asphalt emulsion, 100 percent crushed aggregate, mineral filler, water, and other additives. A selfpropelled continuous loading machine or a truck mounted machine is used to proportion and mix the materials and apply the mixture to the pavement surface. Micro-surfacing is used to retard raveling and oxidation, fill ruts, reduce the intrusion of water, improve surface friction, and remove minor surface irregularities. Pavement Condition Considerations: In the process of selecting pavements suitable for micro-surfacing, the PMS GQL will select some pavements which exhibit distresses beyond the severity practical for micro-surfacing. The majority of these pavements can be acceptable candidates, provided some repairs are made prior to the microsurfacing. The following conditions should be given careful consideration by the pavement review team: Localized wheel track cracking or edge cracking should be repaired full depth with tem I 253. Any potholes must be repaired full depth with Item 255 for composite pavements, and Item 253 for flexible pavements. Areas which exhibit Debonding must be patched in accordance with Item 251. All existing patches must be in good repair prior to micro-surfacing. All existing cracks must be sealed prior to micro-surfacing (See Design Considerations) Crack sealing is not an acceptable treatment for cracks wider than 1"as these cracks should be addressed with partial depth repairs using Item 251, prior to micro-surfacing. The following ex amples of loca lized cracking should be repaired with full depth repairs in accordance with Item 253, prior to a successful micro-surfacing project. Localized wheel track and edge cracking. Localized edge cracking.
Page 14 Traffic Constraints: Micro-surfacing is suitable for all traffic levels. However, where Average Daily Traffic (ADT) is greater than 10,000 vehicles per day a double application of m icro-surfacing is required. This requirement is to insure the wearing surface is durable throughout the intended design life. Design Considerations: The paving mixture is intended to bridge cracks and minor surface irregularities and to achieve a uniform surface without causing skips, lumps, or tears. A sufficient amount of material needs to be specified to allow the contractor to achieve the intended result. A clear understanding of the pay item descriptions and their intended use follows: Item 406 Micro-Surfacing, surface course is to be specified in all non-warrantyapplications assuming the pavement is in an acceptable condition, as detailed above. Item 406 Micro-Surfacing, leveling course is specified in non-wa rranty applications for pavements which display any of the following dist resses: Medium Severity Raveling, Medium Severity Bleeding, or any acceptable cracking distress found at the F requent or Extensive Ex tent. Ca ution is a dvised against specifying a leveling course to e liminate rutting, however, consistent rut depths of less than 3/8 inch can be eliminated with the use of a leveling course. Item 406 Micro-Surfacing, rut fill course is specified in non-warranty applications where non-plastic rutting is found at 3/8 inches or greater along the roadway. Where this Item is necessary the following chart should be used to assist the designer with the quantity calculation for this Item: Micro-Surfacing Rut Filling Yield Chart Average Rut Depth(inches) 1/4" 3/8" 7/16" 1/2" 9/16" 5/8" 11/16" 3/4" 7/8" 1" 1-1/8" 1-1/4" 1-1/2" Aggregate Gradation * A A A A B B B B B B B B B Lbs./SY. Required 15 16 25 28 32 36 40 44 49 54 58 62 66
Page 15 * Aggregate gradation is determined in accordance with Item 406.02 and is determined by the pay item used. This calculation is only necessary for non-warranty applications. Non-warranty micro-surfacing contracts must make prov isions for crack sealing and removal of thermoplastic pavement markings. It is advised to specifyitem 825 Type II or Type III crack sealing with non-warranty micro-surfacing projects. Otherwise crack sealing, Item 825 Type II or Type III, should be done within 6 months prior to a non-warranty micro-surfacing project. Warranty specifications require crack sealing and removal of thermoplastic pavement markings as part of the contract. Both warranty and non-warranty items include the removal of raised pavement markers under 406.08. Item 881 Micro-Surfacing with warranty, sing le course i s t o be speci fied for warranty applications where only a surface is required. A single course should only be considered for pavements with ADT less than 10,000 vehicles per day, and are in good condition with good existing profiles. Item 881 Micro-Surfacing with warranty, multiple course i s speci fied for warranty applications for pavements which display any of the following distresses: Rutting, Medium Severity Raveling, Low or Medium Severity Bleeding, or any acceptable cracking distress found at the Frequent or Extensive Extent. Traffic Control/Releasing Traffic: Traffic is not allowed on the mixture until it has cured sufficiently to prevent pickup by vehicle tires. The new surface is g enerally capable of carry ing normal traffic within one to two hours after application without any damage occurring. Seasonal Construction Limitations: Micro-surfacing specifications require paving to take place between May 1 and Sept. 30. Proper pavement temperature and air temperature is critical to the success of the application. The best time to sell a micro-surfacing contract is in the early spring for completion prior to September, especially when night work is required, thus PM field reviews should be done at the tail end of the winter to insure proper project selection. Anticipated Performance and Service Life: A newly micro-surfaced pavement will have a PCR of 100 initially. The condition of the pavement prior to the micro-surfacing will influence the degradation of the PCR following the micro-surfacing more than any other factor. Althoug h no data currently exists concerning PCR trends of microsurfaced pavements, the expected service life is 5-8 years, and the rate of PCR drop should be similar to that observed since the last hot mix overlay.
Page 16 Specification References: Item 406, Supplemental Specification 881 Unit Cost for Estimating: $1.25-$2.00/sy, ~ $8,000 - $16,000/lane-mile (depends on rut depth). For More Information Contact: Dave Powers, Office of Materials Management, 614-275-1387 Bill Christensen, Office of Highway Management, 614-644-6634 Aric Morse, Office of Pavement Engineering, 614-995-5994
Page 17 Polymer Modified Asphalt Concrete - Flexible and Composite Pavements Description & Purpose: Polymer Modified Asphalt Concrete is a t hin surface, hot applied paving mixture composed of polymer modified asphalt cement mixed with aggregate. A conventional hot mix asphalt plant and asphalt paving machine is used to mix and place the material. T he polymer modified asphalt concrete overlay is used to retard raveling and oxidation, reduce the intrusion of water, improve surface friction, and remove minor surface irregularities. Pavement Condition Considerations: In the process of selecting pavements suitable for a polymer modified asphalt concrete overlay, the PMS GQL will select some pavements which exhibit distresses beyond the severity practical for a polymer modified asphalt concrete overlay. The m ajority of t hese pavements can be accept able candidates, provided some repairs are made prior to the polymer modified asphalt concrete overlay. The following conditions should be given careful consideration by the pavement review team: Over-band crack sealing placed within 1 year of the prospective overlay has the potential to cause problems during construction, creating bumps in the pavement. Localized wheel track cracking or edge cracking should be repaired full depth with Item 253. Any potholes must be repaired full depth with Item 255 for composite pavements, and Item 253 for flexible pavements. Areas which exhibit Debonding must be patched in accordance with Item 251. All existing patches must be in good repair prior to placement of a polymer modified asphalt concrete overlay. Cracks wider than 1" should be addressed with partial depth repairs using Item 251, prior to a polymer modified asphalt concrete overlay. The following cracking examples should be repaired partial depth in accordance with Item 251, prior to a successful polymer modified asphalt concrete overlay project.
Page 18 Traffic Constraints: There are two application Types for this Item. Type A is intended for Low Speed (<45MPH) urban applications. Type B is intended for High Speed (>45 MPH) applications. Design Considerations: The paving mixture is intended to fill cracks and minor surface irregularities to achieve a uniform surface. The pay item for this strategy is Item 854 Polymer Modified Asphalt Concrete, Type, and is payed for by the cubic yard of accepted material in place. Type A is placed at a 5/8 inch thickness. Type B is placed at a 3/4 inch minimum thickness, and can be placed as thick as 1-1/4". Traffic Control/Releasing Traffic: Maintenance of traffic must address the need to restrict traffic until the pavement surface cools below 150 F. Seasonal Construction Limitations: Specifications require air temperature to above 40 F, and the pavement surface temperature to be above 50 F. Anticipated Performance and Service Life: A newly overlayed pavement will have a PCR of 100 initially. The condition of the pavement prior to the poly mer modif ied a sphalt c oncrete ove rlay will inf luence the de gradation of the PCR following the polymer modified asphalt concrete overlay more than any other factor. Although no data currently ex ists con cerning PCR trends of poly mer modified asphalt concrete overlay ed pavements, the expected service life is 7-12 years, and the rate of PCR drop should be similar to that observed since the last hot mix overlay. Specification References: Supplemental Specification 854 Unit Cost for Estimating: $2.00-$4.00/sy, ~ $14,000 - $25,000/lane-mile For More Information Contact: Dave Powers, Office of Materials Management, 614-275-1387 Bill Christensen, Office of Highway Management, 614-644-6634 Aric Morse, Office of Pavement Engineering, 614-995-5994
Page 19 Thin Hot Mix Overlays - Flexible and Composite Pavements Description & Purpose: A thin dense graded hot mix asphalt (HMA) overlay is the highest type alternative available in the pavement preventive maintenance program. Thin overlays protect the pavement structure, reduce the rate of pavement deterioration, correct surface deficiencies, reduce permeabilityand improve the ride quality of the pavement, particularly when accompanied by a scratch course or surface milling. A minor amount of structural enhancement is provided with this PM strateg y. To qualify as preventive maintenance, a dense graded HMA mixture is limited to 2 in thickness as an overlay. Pavement Condition Considerations: In order to assure HMA overlays are specified for the proper pavements and at the proper time, pavement condition must be evaluated. A GQL query of PCR distress codes is an excellent way to produce a preliminary list of HMA candidates. I t is important to underst and that PCR s are representative of the average condition found by the rater, and may not be indicative of an isolated pavement distress. The pavement review team as outlined in ODOT s Pavement Policy is to perform a fi eld revi ew of HMA can didates to i nsure a part icular pavem ent sect ion i s accept able. The following conditions should be given careful consideration by the pavement review team: Over-band crack sealing placed in the year prior of the prospective overlay has the potential to cause problems during construction, creating bumps in the pavement. Pavement areas which display High Severity Raveling or Bleeding should be milled, using ODOT CMS 254, prior to overlay. Localized Medium Severity Wheel Track Cracking should be repaired full depth with Item 253. Where Extensive Wheel Track Cracking is found, further analysis (deflection testing) should be performed, to determine structural integrity. Any potholes must be repaired full depth with Item 255 for composite pavements, and Item 253 for flexible pavements. Areas which exhibit localized De-Bonding must be patched in accordance with Item 251, and all existing patches must be in good repair prior to HMA. Areas which exhibit Medium or Hig h Severity L ongitudinal J oint Cracking should be patched with Item 253.
Page 20 Traffic Constraints: Applicable for all traffic levels provided adequate pavement structure exists. Design Considerations: Thin HMA overlays are not intended to add structure to the pavement. However, it essential to specify the correct material in order to extend pavement life and expect good performance. HMA overlays can include either a scratch course or milling in order to achieve a uniform overlay lift thickness. I t is important to understand the L ift Thickness and Specification Guidelines as provided in the ODOT Pa vement Design & Rehabilitation Manual, Section 404. This section provides g uidance for determination of lift thickness and proper I tem Specification usage. Furthermore, where High Stress Locations exist within the project, reference should b e made to Appendix B of the Pavement Design and Rehabilitation Manual. Crack Sealing is not recommended as a pre-treatment for HMA overlay s. Any full depth repairs done on pa vement or shoulders should include an aggregate drain in the repair where outlet is feasible. Traffic Control/Releasing Traffic: Maintenance of t raffic must address t he need t o restrict traffic until the pavement surface cool s below 150 F. Seasonal Construction Limitations: Specifications require air temperature to above 40 F, and the pavement surface temperature to be above 50 F. Anticipated Performance and Service Life: Anticipated life varies based on overlaythickness and condition of pavement. Pavements which are structurally sound due to a recent minor or major rehabilitation and are treated with a thin HMA overlay are expected to last 8 to 12 years. Specification References: Specification 446 and 448. Supplemental Specifications 856, 858, and 1059 Unit Cost for Estimating: Asphalt: $50 - $60 per Sq. Yd.; Milling: $0.75 - $2.25 per Sq. Yd. For More Information Contact: Dave Powers, Office of Materials Management, 614-275-1387 Bill Christensen, Office of Highway Management, 614-644-6634 Aric Morse, Office of Pavement Engineering, 614-995-5994
Page 21 Concrete Pavement Restoration (CPR) - Rigid Pavements Description & Purpose: CPR consists of pavement g rinding and any combination of pavement repair, grout subsealing, dowel retrofit of cracks, and cleaningand sealing of the joints. The purpose of CPR is to restore ride as well as repair any isolated pavement failures. Pavement Condition Considerations: There is not a GQL query for rigid pavements, as there are only a very small percentage of rigid pavements in the state. There is a wide window of opportunity for cost effective CPR of a rig id pavement. In order to assure CPR is specified for the proper pavements and at the proper time, pavement condition must be evaluated. The intent of PM for rig id pavements i s keep existing pavements as smooth as possible to keep the impact loading to a minimum. By selecting only those pavements which require little or no repair, rigid pavements in need of a higher order of CPR will be left for minor rehabilitation. It should be noted that there are always other pavements which are good candidates for cost effective CPR, but these pavements are more appropriate for minor or major rehabilitation. Traffic Constraints: Applicable for all traffic levels. Design Considerations: CPR covers several strateg ies which can be u sed for both preserving a pavement as well as rehabilitating a pavement. For the purpose of preventive maintenance CPR should concentrate on Supplemental Specification 850 Diamond Grinding Portland Cement Concrete Pavement. It must be emphasized, however, that prior to grinding the pavement for smoothness, some repairs may be required. In most instances it is necessary to restore joint sealing after grinding a pavement. This can be done using Supplemental Specification 80 1 Crack and J oint Cleaning and Sealing with Silicone Sealant. Traffic Control/Releasing Traffic: Maintenance of traffic must address the need to restrict traffic until any pavement repairs are cured. In most instances only one lane at a time needs to be closed. Seasonal Construction Limitations: Pavement repairs require a frost free subgrade. Diamond grinding uses water and needs to be done above freezing temperature.
Page 22 Anticipated Performance and Service Life: CPR as a preventive maintenance strategy is expected to restore the smoothness of the pavement. The ride should remain smooth for at least 5 y ears, and as many as 10 y ears, depending on the distresses evident, the structural integrity of pavement, and the level of truck traffic present. Specification References: Item 255 Full Depth Pavement Removal and Rigid Replacement Item 256 Bonded Patching of Rigid Pavements Supplemental Specification 819 Dowel Bar Retrofit Supplemental Specification 812 Grout Subsealing of Existing Concrete Pavement Supplemental Specification 850 Diamond Grinding Portland Cement Concrete Pavement Supplemental Specification 801Crack and Joint Cleaning and Sealing with Silicone Sealant Unit Cost for Estimating: Estimate $4.00 per square yard for preventive maintenance. For More Information Contact: The Office of Pavement Engineering 614-995-5990 Aric Morse, Dave Miller, Roger Green
Page 23 Drainage Preservation - Flexible, Composite and Rigid Pavements Description & Purpose: This activity is intended to preserve and maintain the performance of the pavement drainage system. The activity consists of cleaningsilt, debris and vegetation at under-drain outlets, as well as replacing crushed or destroyed outlets as needed. Pavement Condition Considerations: GQL lists are not available for this action, since there are no unique pavement condition parameters which indicate drainag e preservation is needed. Drainag e preservation is a critical activity for pavements, especially those constructed with a Free Draining Base. However, this activity should be conducted on all pavements which have under-drain sy stems, as a routine maintenance item, regardless of condition. A list, made by County or District, of the pav ements which have been constructed wit h a Free Draining B ase can be obtained by contacting the Office of Pavement Engineering. Traffic Constraints: As this activity is performed several feet off the shoulder, there are no traffic constraints. Design Considerations: It is recommended the outlets be located by review of the construction plans used for the project responsible for the drainage system. Under-drains which empty into a catch basin or storm sewer system do not need to be inspected. Once the outlets are located, some type of referencing system for future inspections is advised. Inspection Considerations: Under-drain clean out should consist of locating the outlet, removing any silt, debris or vegetation material which has built up, and insuring there is positive connection at the outlet pad. Damaged outlet in need of replacement. Plugged outlet in need of cleaning.
Page 24 Seasonal Limitations: This activity can be done anytime of the year. Anticipated Performance and Service Life: Without routine maintenance of the drainage system the service life of the pavement will be greatly reduced. Specification References: None available. However, there is a concern that high pressure water jet flushing to remove debris can cause damag e of the sy stem. Geo-Composite edg e drain sy stems are never appropriate for pressurized cleaning. Unit Cost for Estimating: $2,000 - $5,000 per mile. For More Information Contact: David Riley, Office of Structural Engineering, 614-466-2599 Randy Morris, Office of Highway Management, 614-644-6638 Aric Morse, Office of Pavement Engineering, 614-995-5994
Appendix - GQL Logic Page 25 CRACK SEAL ---------- FLEXIBLE PAVEMENT 75<PCR<90, Unlimited ADT, 2-Lane & 4-Lane DISTRESS Raveling Bleeding Patching Potholes/Debonding Crack Seal Deficiency Rutting Settlement Corrugations Wheel Track Cracking Block and Transverse Cracking Longitudinal Joint Cracking Edge Cracking Random Cracking ACCEPTABLE L:OFE, M:O None L:O, M:O L:O OFE L:OFE, M:O L:OFE L:O L:OFE, M:O L:OFE L:OF L:OF, M:OF CRACK SEAL ---------- COMPOSITE PAVEMENT 75<PCR<90, Unlimited ADT, 2-Lane & 4-Lane DISTRESS Raveling Bleeding Patching Surface Disintegration/De-bonding Rutting Pumping Shattered Slab Settlement Joint Reflection Cracking (unjointed base transverse) Intermediate Transverse Cracking Longitudinal Joint Cracking Pressure Damage/Upheaval Crack Sealing Deficiency ACCEPTABLE L:OFE, M:O None L:O. M:O L:O L:OFE, M:O L:O, M:O L:OFE, M:OFE L:OFE, M:OFE L:OFE, M:O OFE
Appendix - GQL Logic Page 26 SINGLE CHIP SEAL ---------- FLEXIBLE PAVEMENT 70<PCR<90, ADT<2500, ADTT<250, 2-Lane only DISTRESS Raveling Bleeding Patching Potholes/Debonding Crack Seal Deficiency Rutting Settlement Corrugations Wheel Track Cracking Block and Transverse Cracking Longitudinal Joint Cracking Edge Cracking Random Cracking ACCEPTABLE L:OFE None L:O, M:O, H:O L:O, M:O, H:O L:OFE L:O L:OF L:OFE L:OF, M:O L:OFE, M:OFE L:OF, M:O, H:O L:OFE, M:OF, H:O SINGLE CHIP SEAL ---------- COMPOSITE PAVEMENT 70<PCR<90, ADT<2500, ADTT<250, 2-Lane only DISTRESS Raveling Bleeding Patching Surface Disintegration/De-bonding Rutting Pumping Shattered Slab Settlement Joint Reflection Cracking Intermediate Transverse Cracking Longitudinal Joint Cracking Pressure Damage/Upheaval Crack Sealing Deficiency ACCEPTABLE L:OFE None L:O, M:O, H:O L:O, M:O, H:O L:OFE None None L:OFE L:O L:OFE, M:O L:O
Appendix - GQL Logic Page 27 SINGLE APPLICATION MICRO-SURFACE ---------- FLEXIBLE PAVEMENT 70<PCR<90, ADT<10,000, 2-Lane & 4-Lane DISTRESS ACCEPTABLE Raveling L:OFE Bleeding M:O Patching L:O, M:O, H:O Potholes/De-bonding L:O, M:O, H:O Crack Seal Deficiency Rutting L:OFE Settlement Corrugations L:OF Wheel Track Cracking L:OF, M:O Block and Transverse Cracking L:OF, M:O Longitudinal Joint Cracking L:OFE, M:OFE Edge Cracking L:OF, M:O, H:O Random Cracking L:OFE, M:O, H:O DOUBLE APPLICATION MICRO-SURFACE ---------- FLEXIBLE PAVEMENT 70<PCR<90, Unlimited ADT, 2-Lane & 4-Lane DISTRESS ACCEPTABLE Raveling L:OFE, M:OFE Bleeding M:OFE Patching L:OF, M:OF, H:OF Potholes/De-bonding L:OF, M:OF, H:OF Crack Seal Deficiency Rutting L:OFE, M:OF, H:O Settlement Corrugations L:OF, M:O Wheel Track Cracking L:OF, M:O Block and Transverse Cracking L:OFE, M:OF Longitudinal Joint Cracking L:OFE, M:OFE Edge Cracking L:OFE, M:O, H:O Random Cracking L:OFE, M:OF, H:O
Appendix - GQL Logic Page 28 SINGLE APPLICATION MICRO-SURFACE ---------- COMPOSITE PAVEMENT 70<PCR<90, ADT<10,000, 2-Lane & 4-Lane DISTRESS ACCEPTABLE Raveling L:OFE Bleeding L:OFE, M:O Patching L:O, M:O, H:O Surface Disintegration/De-bonding L:O, M:O, H:O Rutting L:OFE Pumping None Shattered Slab Settlement Joint Reflection Cracking (unjointed base transverse) L:OFE Intermediate Transverse Cracking L:O Longitudinal Joint Cracking L:OFE, M:O Pressure Damage/Upheaval L:O Crack Sealing Deficiency DOUBLE APPLICATION MICRO-SURFACE ---------- COMPOSITE PAVEMENT 70<PCR<90, Unlimited ADT, 2-Lane & 4-Lane DISTRESS ACCEPTABLE Raveling L:OFE, M:OFE Bleeding M:OFE Patching L:O, M:O, H:O Surface Disintegration/De-bonding L:O, M:O, H:O Rutting L:OFE, M:OF, H:O Pumping None Shattered Slab Settlement Joint Reflection Cracking (unjointed base transverse) L:OFE, M:OFE Intermediate Transverse Cracking L:O, M:O Longitudinal Joint Cracking L:OFE, M:OFE Pressure Damage/Upheaval L:O Crack Sealing Deficiency
Appendix - GQL Logic Page 29 POLYMER MODIFIED ASPHALT CONCRETE---------- FLEXIBLE PAVEMENT 70<PCR<90, Unlimited ADT, 2-Lane & 4-Lane DISTRESS ACCEPTABLE Raveling L:OFE, M:OFE Bleeding M:O Patching L:O, M:O, H:O Potholes/De-bonding L:O, M:O, H:O Crack Seal Deficiency Rutting L:OFE Settlement Corrugations L:OF Wheel Track Cracking L:OF, M:O Block and Transverse Cracking L:OF, M:O Longitudinal Joint Cracking L:OFE, M:OFE Edge Cracking L:OF, M:O, H:O Random Cracking L:OFE, M:O, H:O POLYMER MODIFIED ASPHALT CONCRETE---------- COMPOSITE PAVEMENT 70<PCR<90, Unlimited ADT, 2-Lane & 4-Lane DISTRESS ACCEPTABLE Raveling L:OFE, M:OFE Bleeding L:OFE, M:O Patching L:O, M:O, H:O Surface Disintegration/De-bonding L:O, M:O, H:O Rutting L:OFE Pumping None Shattered Slab Settlement Joint Reflection Cracking (unjointed base transverse) L:OFE Intermediate Transverse Cracking L:O Longitudinal Joint Cracking L:OFE, M:O Pressure Damage/Upheaval L:O Crack Sealing Deficiency
Appendix - GQL Logic Page 30 THIN HOT MIX OVERLAY ---------- FLEXIBLE PAVEMENT 70<PCR<90, Unlimited ADT, 2-Lane & 4-Lane DISTRESS ACCEPTABLE Raveling L:OFE, M:OFE, H:OFE Bleeding M:OFE, H:OFE Patching L:OF, M:OF, H:OF Potholes/De-bonding L:OF, M:OF, H:OF Crack Seal Deficiency Rutting L:OFE, M:OFE, H:OFE Settlement Corrugations L:OFE, M:OFE Wheel Track Cracking L:OF, M:O Block and Transverse Cracking L:OFE, M:OF Longitudinal Joint Cracking L:OFE, M:OFE Edge Cracking L:OFE, M:OF, H:O Random Cracking L:OFE, M:OF, H:O THIN HOT MIX OVERLAY ---------- COMPOSITE PAVEMENT 70<PCR<90, Unlimited ADT, 2-Lane & 4-Lane DISTRESS ACCEPTABLE Raveling L:OFE, M:OFE, H:OFE Bleeding M:OFE, H:OFE Patching L:OF, M:OF, H:OF Surface Disintegration/De-bonding L:OFE, M:OFE, H:OFE Rutting L:OFE, M:OFE, H:OFE Pumping None Shattered Slab Settlement Joint Reflection Cracking (unjointed base transverse) L:OFE, M:OFE Intermediate Transverse Cracking L:O, M:O Longitudinal Joint Cracking L:OFE, M:OFE Pressure Damage/Upheaval L:O, M:O, H:O Crack Sealing Deficiency