Moisture Sensitivity of Asphalt Pavements (2003)

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AASHTO Survey

State Treat for Moisture Damage Problems in HMA Pavements Treatment Method / Approach Test for Moisture Susceptibility Test Method(s) Used Stage When Testing Is Done Currently Funds Moisture Damage Research Research Topics YES Alabama requires any mixes with less than 80% TSR or that show any signs of visual stripping to use antistrip. Both liquid and lime antistrips are allowed. Liquid antistrips are more economical for the contractor. YES Modified AASHTO T283 (without the freeze cycle and with less "curing " time). During mix design, field QC, and field QA. YES Two research projects under way related to moisture in HMA. NCAT is doing the research. Contact NCAT for details. 1. Measurement of Rate of Water Intrusion into Pavement Layers Constructed with Superpave- Designed Asphalt Concrete. 2. Development of HMA Moisture Susceptibility Test for Alabama. Liquid Tensile Mix / Acceptance YES Liquid antistrip agent. YES A variation of static immersion test. During the mix design to determine the amount of liquid antistrip to add to the asphalt cement. NO N/A Liquid Compressive Mix YES, if it is indicated as necessary during the HMA design phase. In such case, an antistrip additive must be used. If an antistrip additive is needed, a heat-stable liquid antistrip additive from the Qualified Products List shall be added at the rate of 0.5% or 0.75% by weight of the asphalt binder as determined by laboratory analysis. YES All mix designs are required to be tested for water sensitivity. The agency uses a test modified from an Asphalt Institute test several years ago. Water sensitivity is based on Marshall stabilities before and after conditioning for stripping potential. AHTD Test Method 455A is used; 6-in. gyratory samples are used as test specimens. At the design phase. The contractor is required to design the HMA and provide samples for the design to be verified by the department. The department does not normally verify the water sensitivity test results. In the recent past, the department has used a high percentage of modified asphalt binders, PG 70-22 and PG 76-22, and few designs have required antistrip. YES: One just concluded: TRC- 9804 "ERSA" (Evaluator of Rutting and Stripping in Asphalt) Wheel Track Testing for Rutting and Stripping; Principal Investigator: Dr. Kevin Hall, Univ. of Arkansas. Primary objective was to develop test specs for determining the rutting and/or stripping potential of an asphalt concrete mix using ERSA, to supplement the Superpave mix design procedure for asphalt concrete. A follow-up research project has just begun: TRC-0201, "ACHM Lab Test for Rutting and Stripping"; Principal Investigator: Dr. Kevin Hall, Univ. of Arkansas. Two main global objectives of the research: to finalize criteria for judging mix acceptability relative to the stripping potential of an asphalt mix and to develop mixture design specs for relatively high- performance ACHM targeted for use in intersections. Liquid Stability Mix YES YES NO N/A Treatments are used if the I/C fails. This is about 98% of the time. Lime or portland cement is added to moist aggregates (4% moisture). Immersion / compression test similar to AASHTO T165. Mix design only - no field acceptance. Lime Compressive Mix AZ AR AK RESULTS OF SURVEY ON MOISTURE DAMAGE OF HOT-MIX ASPHALT PAVEMENTS August 4, 2002 Compiled by Tim Aschenbrener, Colorado Department of Transportation AL

State Treat for Moisture Damage Problems in HMA Pavements Treatment Method / Approach Test for Moisture Susceptibility Test Method(s) Used Stage When Testing Is Done Currently Funds Moisture Damage Research Research Topics RESULTS OF SURVEY ON MOISTURE DAMAGE OF HOT-MIX ASPHALT PAVEMENTS August 4, 2002 Compiled by Tim Aschenbrener, Colorado Department of Transportation YES Liquid antistripping additive added at the hot plant. Hydrated lime slurry and marination. NO, not at this time Caltrans is in the process of implementing a test similar to AASHTO T283 for next construction season. NO None Liquid / Lime YES Canada allows both liquid and hydrated lime. However, it only permits the use of lime for dolomitic limestone in dense friction courses. Aggregates are allowed to be prelimed at the supply/quarries provided contractor's QC plan clearly states how the quality in the aggregates is assured before use prior to mixing. Drum premixing with wet aggregates and lime slurry in stockpile are permitted in the specs. YES Stripping potential is assessed by Ontario Laboratory Standard Immersion Marshall (vacuum saturation ratio of wet to dry retained stability >70%), Superpave AASHTO T283. (Studies showed Ontario method equates well with AASHTO T283.) At mix design and verified by QA. NO, not currently. But had jointly funded a project a few years back with Transport Association of Canada. The study was to compile a background document on causes, identification, testing, and mitigation of moisture damage of asphalt pavements and antistripping additives (where methods by Ontario and AASHTO were compared). Liquid / Lime Stability Mix / Acceptance YES Colorado requires hydrated lime. Dry lime on wet aggregates is most commonly used. Lime slurry and marinating are also allowed. YES Modified AASHTO T283. Similar to the original Lottman test. For mix design, field QC, and field QA. NOT at this time None Lime Tensile Mix / Acceptance NO Conditional YES: Only for Superpave mixes. AASHTO T283 As part of the mix design performed by the contractor. NO N/A None Tensile Mix YES Antistrip agents are required in all mixes. Liquid or hydrated lime in slurry form is used. YES ASTM D4867. Mix design. NO N/A Liquid / Lime Tensile Mix NO Aggregates are very good for HMA. No treatments have been needed. YES AASHTO T283. Mix design only. NO N/A Tensile Mix CO CT DC DE CA Canada (Ontario)

State Treat for Moisture Damage Problems in HMA Pavements Treatment Method / Approach Test for Moisture Susceptibility Test Method(s) Used Stage When Testing Is Done Currently Funds Moisture Damage Research Research Topics RESULTS OF SURVEY ON MOISTURE DAMAGE OF HOT-MIX ASPHALT PAVEMENTS August 4, 2002 Compiled by Tim Aschenbrener, Colorado Department of Transportation YES Florida will allow either liquid antistrip (most common approach) or lime (either added in the mixing operation before the addition of the asphalt cement or as a slurry in the aggregate). YES Modified AASHTO T283 with a retained strength of 80%, a minimum unconditioned tensile strength of 120 psi, and a higher saturation level. For the mix design. YES Florida has a contract looking at the basics of moisture damage and focusing on the standardization of the conditioning procedure. Liquid / Lime Tensile Mix YES Georgia requires hydrated lime. The addition of hydrated lime to the aggregate may be accomplished by Method A or B as follows: Method A: dry form; Method B: lime/water slurry. YES Modified Lottman test, GDT-66. Every mix design, and field QC/QA samples. NO, not at this time. N/A Lime Tensile Mix / Acceptance NO NO NO None None YES Iowa does treat for moisture damage when aggregate blend contains a high percentage of siliceous aggregates. Most of Iowa's mixtures use limestone or dolomite. Until this year, hydrated lime was required for treating moisture damage. The agency was forced by the industry to allow liquid antistrips this year. Conditional YES: Only test for moisture susceptibility when liquid antistrips are used or when the contractor attempts to prove that an antistrip is not needed even though the aggregates used would require it by specs. AASHTO T283. Testing is performed on the mix design by the contractor and on QA samples by the agency. YES: Funding research with Iowa State University to develop a more reliable test. The research in progress is intended to find a dynamic test for moisture damage that will simulate the high hydraulic pressure encountered in pavements under traffic. Liquid Tensile Mix / Acceptance YES Essentially all plant mix contains antistrip. Typically 1/2%. The respondent is pushing for a comeback to hydrated lime. YES Immersion Compression AASHTO T165. As part of the mix design confirmation. Consultants include test in mix design. NO N/A Liquid Compressive Mix YES Illinois uses liquid antistrip when an additive is required. Hydrated lime is also allowed and has been required on a couple of contracts awarded this year. Primarily liquids are used. YES Modified AASHTO T283. During mix design with a TSR criterion of 0.75 or greater. NO None Liquid Tensile Mix ID IL IA FL GA HI

State Treat for Moisture Damage Problems in HMA Pavements Treatment Method / Approach Test for Moisture Susceptibility Test Method(s) Used Stage When Testing Is Done Currently Funds Moisture Damage Research Research Topics RESULTS OF SURVEY ON MOISTURE DAMAGE OF HOT-MIX ASPHALT PAVEMENTS August 4, 2002 Compiled by Tim Aschenbrener, Colorado Department of Transportation Yes; only a small percentage (about 10%) need it. Almost exclusively liquid antistrip. YES AASHTO T283 with no modifications. The freeze-thaw cycle is required. Mix design only. Not at this time. Liquid / None Tensile Mix YES Kansas allows liquid antistrip agents or lime. Liquids are by far the most commonly used. Approximately 30% to 50% of the mix designs require treatment. YES Modified AASHTO T283. Kansas test on design and samples from behind the paver are tested for QC and QA. NO; watching the national effort. None Liquid Tensile Mix / Acceptance YES Kentucky uses liquid antistripping additives exclusively. Hydrated lime is an option, but no contractors use it. YES Slightly modified version of ASTM D4867. Kentucky tests for moisture damage in the mix design phase by specification and occasionally in the field for information. NO Not applicable. Liquid Tensile Mix YES Louisiana requires liquid antistrip and Lottman with one freeze-thaw cycle for mix design approval. Louisiana also requires modified asphalts, which have improved resistance to moisture. YES Modified AASHTO T283. Similar to the original Lottman test with one freeze-thaw cycle. At design submittal, at plant for JMF verification, and again every 40,000 tons. NO: Louisiana is not but has in the past. None Liquid Tensile Mix NO Not much treatment is done. If any treatment is used, it is typically a liquid antistripping additive. NO N/A NO O Some may be done in the future on Superpave requirements. None YES Chemical YES ASTM D4867. Mix design, field QC and QA. NO N/A Liquid Tensile Mix / Acceptance NO N/A O N/A N/A N N NO No, but discussions on this are in progress. None YES Allow antistrip agents. Contractors choose the manufacturer and recommended dosage. YES AASHTO T283 or ASTM D4867; whichever the contractor chooses. The test is required for mix design, and field samples are requested if the results from the TSR test are deemed marginal or if the materials used in the mixture are from a questionable source. NO N/A Liquid Tensile Mix / Acceptance ME MI KY LA MA MD IN KS

State Treat for Moisture Damage Problems in HMA Pavements Treatment Method / Approach Test for Moisture Susceptibility Test Method(s) Used Stage When Testing Is Done Currently Funds Moisture Damage Research Research Topics RESULTS OF SURVEY ON MOISTURE DAMAGE OF HOT-MIX ASPHALT PAVEMENTS August 4, 2002 Compiled by Tim Aschenbrener, Colorado Department of Transportation YES Allow liquid antistripping additives. They are needed in approximately 30% of the mixes. YES A version of ASTM D4867 is used. Mix design and field acceptance. NO N/A Liquid Tensile Mix / Acceptance YES The contractor is given the option of hydrated lime or a commercial antistrip additive. Although lime was primarily used in the past, liquids are the primary treatment used at this time. YES AASHTO T283 with one freeze-thaw cycle is used. Currently the mix design is tested; testing of field cores is being investigated. YES The testing of plant-produced mix and field cores is being investigated. Liquid Tensile Mix YES With hydrated lime - dry lime on wet aggregate. Note: failing test. YES Modified AASHTO T283. Similar to the original Lottman test. For mix design, field QC, and field QA. NO N/A Lime ensile Mix / Acceptance YES Montana requires hydrated lime. Dry lime added on the cold feed is most common. YES Modified AASHTO T283. Similar to the original Lottman test. For the mix design. NO None Lime T Tensile Mix YES The use of an antistrip additive is required: either hydrated lime, chemical additive, or a combination of the two as needed to obtain the TSR requirements. YES Modified AASHTO T283 with no freeze- thaw cycle. Testing is required both during mix design and during production. NO N/A Liquid / Lime Tensile Mix / Acceptance NO North Dakota has in past years, but recently including additions into the mix has been suspended. Testing is currently being increased, and treatments may be included in future projects. Lime was the predominant addition. YES Modified Lottman. Mix design. NO N/A None Tensile Mix MN ND MO MS MT NC

State Treat for Moisture Damage Problems in HMA Pavements Treatment Method / Approach Test for Moisture Susceptibility Test Method(s) Used Stage When Testing Is Done Currently Funds Moisture Damage Research Research Topics RESULTS OF SURVEY ON MOISTURE DAMAGE OF HOT-MIX ASPHALT PAVEMENTS August 4, 2002 Compiled by Tim Aschenbrener, Colorado Department of Transportation YES Nebraska allows the contractor to select which antistrip additive is used; liquid additives are being used. Whatever liquid additive is used, it must be added to the binder by the supplier and the binder must meet MP-1 after antistrip is added. YES AASHTO T283. For mix design approval. If an antistrip is required, the agency samples at project start-up to verify the design and then make adjustments whenever the TSR is less than 80%. If above or once above 80%, no more samples are taken during production. Not at this time. None Liquid Tensile Mix / Acceptance NO NO New Hampshire has tested for moisture susceptibility in the past, but because no problems have been revealed in the test results or historically in the field, this testing has been discontinued. N/A NO N/A None Not routinely. On the few occasions that the agency has treated, it has used liquid antistrip, but the respondent is not convinced of the efficacy of these treatments. YES AASHTO T283. New Jersey requires T283 at time of design only. NO None None Tensile Mix YES New Mexico requires 1.5% lime in all asphalt concrete mixes. YES AASHTO T165. For mixture design acceptance (laboratory). NO N/A Lime compressive Mix YES NDOT uses hydrated lime added to damp aggregate and stockpiled for a minimum of 48 hours. YES Modified AASHTO T283 Lottman with freeze-thaw cycle. During the mix design and on samples taken from behind the paver. NO: not at this time. N/A Lime Tensile Mix / Acceptance YES: only when aggregates from specific area of the state are used. This is about 10%. The agency leaves it up to the producers to use any additives as long as the TSR minimum value is achieved. On the basis of the test results, liquid antistripping additives are most commonly used. Polymer- modified asphalts also seem to help. Conditional YES: NYSDOT does not test routinely unless necessary. The testing is generally left up to the producer. If necessary to test, New York uses AASHTO T283. During the mixture design phase. NO None. However, the agency has placed small test sites in one area of the state where gravel is the predominant aggregate. These sites were placed to investigate effects of different additives in the HMA in relation to moisture damage. Liquid / None Tensile Mix NV NY NE NH NJ NM

State Treat for Moisture Damage Problems in HMA Pavements Treatment Method / Approach Test for Moisture Susceptibility Test Method(s) Used Stage When Testing Is Done Currently Funds Moisture Damage Research Research Topics RESULTS OF SURVEY ON MOISTURE DAMAGE OF HOT-MIX ASPHALT PAVEMENTS August 4, 2002 Compiled by Tim Aschenbrener, Colorado Department of Transportation Not routinely. Lime or liquid is allowed but must raise to passing level. YES AASHTO T283 with some modifications in air voids and saturation. Mix design only routinely, but can test by spec at any time. YES Ohio has a study to look at 6 inch versus 4 inch and overall AASHTO T283 procedure. Rarely treat. None Tensile Mix YES Chemical antistrip additives are used almost exclusively. Lime has been used for some gravel mixtures, but this is rare. YES OHD L-36 for Hveem mix designs. It is similar to AASHTO T283, which is used for Superpave mixtures. For mix design and field control tests. Mix design T283's TSR is required to be 0.80 minimum. 0.75 is required as a field criterion. OHD L-36 requires 75% retained strength after the freeze-thaw cycle for both field and mix design. In the field it is a go-no go type of spec. Resident engineers decide whether the project may continue if failing results are found. No mix design is transferred if three consecutive failures occur on that mix design. YES, surface energy research on some aggregates and binders is being funded at the University of Oklahoma. Surface energies for a few aggregates in mixtures that failed moisture sensitivity tests and control aggregates and some asphalt binders will be examined. The actual surface energy testing will be performed at Texas A&M. Both universities will collaborate. Texas A&M, through the Texas Transportation Institute, presented a paper at Association of Asphalt Paving Technologies this year. Liquid Tensile Mix / Acceptance YES Oregon uses different treatments depending on location and risk of stripping. The use of lime is mandated in the most severe climates. In less severe areas lime, ultra-pave, or other liquid antistrip agents are allowed on the basis of results of TSR testing. When lime is used, dry lime on wet aggregates is used almost exclusively. YES AASHTO T283. During the mix design phase and again early on during production. Not at this time. N/A Liquid / Lime Tensile Mix / Acceptance YES; not often. Predominately, Pennsylvania's HMA plants have elected to use chemical additives added directly to the asphalt cement. A very low percentage of mixes require treatment. YES Modification of AASHTO T283. Required as part of mix design approval. NO N/A Liquid / None Tensile Mix YES Liquid antistrip is required in friction courses. NO N/A N/A NO N/A Liquid OR PA RI OH OK

State Treat for Moisture Damage Problems in HMA Pavements Treatment Method / Approach Test for Moisture Susceptibility Test Method(s) Used Stage When Testing Is Done Currently Funds Moisture Damage Research Research Topics RESULTS OF SURVEY ON MOISTURE DAMAGE OF HOT-MIX ASPHALT PAVEMENTS August 4, 2002 Compiled by Tim Aschenbrener, Colorado Department of Transportation YES South Carolina requires hydrated lime. The agency requires to damp mix hydrated lime in a pug mill with at least 3% moisture in the aggregate. This system has worked for South Carolina for some time now. YES Modified AASHTO T283. For mix design and has an option for field QC. NO None: In the past, both South Carolina and Georgia had done extensive research in the area of hydrated lime use for moisture susceptibility purposes and should have several good research reports on this topic. Lime ensile Mix YES South Dakota requires hydrated lime. YES ASTM D486 for Marshall mix designs and AASHTO T283 for Superpave mix designs. At the mix design stage by the contractor with DOT verification. YES South Dakota is in third year of a 3-year study on moisture damage. Peter Sebaaly from the University of Nevada is the researcher evaluating the use of hydrated lime and liquid antistripping agents. South Dakota would like to find a moisture damage test that could be conducted in the field in less time than the current AASHTO T283 procedure. Lime T Tensile Mix YES A majority of the mixes require treatment. Liquid antistripping additives are used. YES A version of AASHTO T283 is used. Mix design and field acceptance. NO N/A Liquid Tensile Mix / Acceptance YES Texas allows hydrated lime or liquid antistrip agents that prove effective. Lime works best on siliceous aggregates but is not always effective on limestone (yes, limestone can strip). YES Modified AASHTO T283. Similar to the original Lottman test. Texas is looking at eliminating this test in favor of the Hamburg wheel track test results. The Hamburg is the more severe test. Test for mix design. A companion Louisiana boil test is performed on mix that passes the modified Lottman. The Louisiana boil test is performed during production (QC) and is used to screen for running the modified Lottman. If the boil test fails, the agency runs the modified Lottman as a QA. The agency also runs Hamburg on the mix design (either lab or trial batch). The agency runs at least one additional Hamburg during production; however, the agency can run as many as needed to verify mix compliance. YES; Texas is currently supporting a pooled-fund study, and the agency continues to support Hamburg testing research. Stripping and Hamburg testing. Liquid / Lime Tensile/Hamburg Mix / Acceptance SD TN TX SC

State Treat for Moisture Damage Problems in HMA Pavements Treatment Method / Approach Test for Moisture Susceptibility Test Method(s) Used Stage When Testing Is Done Currently Funds Moisture Damage Research Research Topics RESULTS OF SURVEY ON MOISTURE DAMAGE OF HOT-MIX ASPHALT PAVEMENTS August 4, 2002 Compiled by Tim Aschenbrener, Colorado Department of Transportation YES Utah uses a hydrated lime slurry with three parts water and one part lime by weight. The lime content is 1.0% by weight of the aggregate. Marinating is also allowed, but with 1.5% lime. YES AASHTO T283 and the Hamburg rut test. Mix design approval. Utah reserves the right to spot test if it perceives a problem. NO N/A Lime Tensile/Hamburg Mix YES Virginia allows either hydrated lime or chemical antistripping additive. If hydrated lime is used, it must be applied to moist aggregate (at least 3% moisture). Liquid antistripping additives are used almost exclusively. YES AASHTO T283. During mix design; depending on the district, production is occasionally checked. YES Virginia has a current project to try to determine whether the magnitude of visual stripping observed in a statewide coring survey several years ago is detrimental from a reduced service-life standpoint. Note: cores revealed quite a bit of visual stripping but mostly only cracking as a distress. The agency is simulating various degrees of stripping on laboratory specimens and running fatigue tests on the specimens. Liquid Tensile Mix YES Vermont requires the use of an antistrip additive in any mix that contains granite or quartzite materials unless testing shows otherwise. The agency requires a minimum of 0.50% additive. When required, all producers currently use a liquid additive. The additive is generally "Wet-Fix 312" produced by Akzo Nobel. Hydrated lime is acceptable but not required. Additive can be blended in asphalt storage tank or added by an in-line injection system. Most use injection system. Conditional YES: only on new aggregate sources and all Superpave designs. AASHTO T283 is used with 4-inch specimens. Testing is done prior to acceptance of any new aggregate source and is required on all Superpave designs. Designing of all mixes is the responsibility of mix producer. NO; not to the respondent's knowledge. N/A Liquid Tensile Mix YES Washington uses liquid antistrip, on the basis of results from a modified Lottman test. YES Modified Lottman. At the time the design mix is developed in the agency's laboratory. This is true for all mixes. NO, not directly, although several groups with which the agency is affiliated are reviewing moisture susceptibility tests. None Liquid Tensile Mix WA UT VA VT

State Treat for Moisture Damage Problems in HMA Pavements Treatment Method / Approach Test for Moisture Susceptibility Test Method(s) Used Stage When Testing Is Done Currently Funds Moisture Damage Research Research Topics RESULTS OF SURVEY ON MOISTURE DAMAGE OF HOT-MIX ASPHALT PAVEMENTS August 4, 2002 Compiled by Tim Aschenbrener, Colorado Department of Transportation YES Contractors are allowed to use either hydrated lime or liquid antistripping agents (any liquid agents used are further restricted by specification limits that tie to changes in the viscosity and penetration of the original asphalt binder). Liquid antistripping agents have been the additive of choice for the agency's contractors since about 1994-1995 (otherwise a lot of hydrated lime was seen here as well). YES ASTM D4867 with a minimum threshold limit of 70% without the aid of additives, and a minimum 75% if additives are being used. It is required as part of meeting original mix design parameters, but only requires field QC testing if a mixture had indicated the need for use of an antistripping agent. At the present time, the department does not do any sampling or testing as part of its QA verification process (dependent on contractor data during production). YES Research was funded 3 years ago and is currently ending an additional funded project from 2001-2002 budgets. The title is "Evaluation of the Extent of HMA Moisture Damage in Wisconsin as it Relates to Pavement Performance." Liquid Tensile Mix NO West Virginia has not had moisture damage issues. NO N/A N/A NO N/A None YES Wyoming requires hydrated lime. Dry lime on wet aggregate is most commonly used. Slurry is allowed, and marinating would be allowed if precautions are taken to prevent leaching. YES Modified AASHTO T283 with freeze cycle. Will most likely use the new T283 without modification when it is published. Wyoming requires for mix design testing and does some mixture checks; no QA testing at this time. NO None Lime ensile Mix YES: it is required on all mixes with the exception of CA or limestone aggregates. Dry lime on wet aggregates through a pug mill with at least 15 seconds of retention time. YES AASHTO T283 for Superpave and compaction is allowed by either Kneading (T247) or gyratory compactor. ICs are used for Hveem mixes. Mix design and on test strip samples. NO None Lime T Tensile Mix / Acceptance YES, when needed. 99% of the time, liquid antistrip is used. YES AASHTO T283. Mix design only. NO None Liquid Tensile Mix YES Hydrated lime added to wet aggregates and mixed prior to entering the heating and mixing drum. YES AASHTO T165 and T167 Immersion- Compression. Mix design. NO None Lime Compressive Mix FHWA (WFLHD) WV WY FHWA (CFLHD) FHWA (EFLHD) WI

State Treat for Moisture Damage Problems in HMA Pavements Treatment Method / Approach Test for Moisture Susceptibility Test Method(s) Used Stage When Testing Is Done Currently Funds Moisture Damage Research Research Topics RESULTS OF SURVEY ON MOISTURE DAMAGE OF HOT-MIX ASPHALT PAVEMENTS August 4, 2002 Compiled by Tim Aschenbrener, Colorado Department of Transportation YES/NO Tally Type of Treatment YES/NO Tally Type of Test Time of Test YES/NO Tally See above topics. 42 YES's 25 Liquid antistripping additive 44 YES's 39 Tensile (AASHTO T283, ASTM D4867, etc.) 30 Mix design only 11 YES's 3 YES(not often) 7 Liquid or lime 4 YES's with condition 5 Compressive test (AASHTO T165) 18 Mix design and field acceptance 44 NO's 10 NO's 13 Hydrated lime total 7 NO's 2 Retained stability Breakdown of Hydrated Lime Total 2 Wheel-tracking and tensile test 15 Dry lime on wet aggregates 6 Lime slurry 4 Lime slurry and marination TOTAL 55 45 55 48 48 55 SUMMARY: A total of 55 responses have been received and tabulated in this survey. A brief summary of the results is given below:

TOPIC 2 Chemical and Mechanical Processes of Moisture Damage in Hot-Mix Asphalt Pavements