ITEM 401 ASPHALT CONCRETE FIELD OPERATIONS
401.01 Description. This specification describes the field operation requirements for placing all
types of asphalt concrete material used in pavement surface, intermediate, and base courses. Deviations from these general requirements are covered in the specific requirements for each material type according to the appropriate contract item or items. Use an approved Job Mix Formula (JMF). Control all field operations to ensure that the mixture placed is uniform in composition, conforms to the specification requirements, is free of any defect (ex. segregation, tenderness, lack of mixture and texture uni formity, raveling, flushing, rutting, holes, debris, etc.) within the Contractor’s control at project completion.
401.02 Materials. Furnish materials conforming to:
Asphalt material (401.06, 401.08.D, 401.11) ..................... ........................................ 702.01, 702.04, ........................ 702.09, 702.12, or 702.13 Hot applied joint sealer…………… 702.17 Type 1
401.03 Equipment. Provide equipment meeting the requirements below:
A.Hauling Equipment. Use trucks for hauling asphalt concrete that have tight, clean, smooth metal beds. Equip all truck beds with a securely fastened, waterproof cover of suitable material to protect the mixture from wind and weather during transport. In addition to covers, insulate all truck beds if transporting asphalt concrete at prevailing air temperatures below 50 °F (10 °C) or if the haul distance exceeds 20 miles (32 km).
B.Spreading Equipment. Use self -contained spreading equipment of sufficient size, power, and stability to receive, distribute, and strike-off the asphalt concrete at rates and widths meeting the typical sections and other details shown on the plans. Use spreading equipment tha t has automatic control systems that maintain the screed in a constant position relative to profile and cross -slope references. Ensure control of the screed position is reasonably independent of irregularities in the underlying surface and of the spreader operation. Equip asphalt spreading equipment to prevent segregation of the asphalt concrete when the material moves from the hopper to the screed. Use means and methods approved by the asphalt spreader manufacturer consisting of but not limited to any comb ination of chain curtains, deflector plates, kickback panels, reverse augers, or other such devices. When a safety edge is required, attach a device to the screed that confines the material at the end gate and extrudes it in such a way that results in a compacted wedge shape pavement edge of approximately 30 degrees and not steeper than 40 degrees. Ensure the device maintains contact with the prepared surface and allows for transition to crossroads, driveways, and obstructions. Do not use conventional single plate strikeoff. Obtain the Engineer’s approval for short sections of handwork when necessary for transitions, turnouts, or other areas. The Engineer will base final approval of spreading equipment on the demonstrated capability of the equipment to place the mixture to the required cross-section, profile and alignment in an acceptable, finished condition ready for compaction. Where the use of standard full -scale spreading equipment is impractical due to the size or irregularity of the area to be paved, use specialized equipment or hand methods approved by the Engineer to spread the asphalt concrete.
C.Anti-Segregation Equipment. When anti-segregation equipment is specified, provide a Material Transfer Vehicle (MTV) with paver hopper insert; a Material Transfer Device (MTD) with paver hopper insert; or a remixing paver specifically manufactured to eliminate segregation. Use paver hopper inserts with a minimum capacity of 10 tons (9 metric tons). Remixing may be done by the MTV, MTD, in the paver hopper insert, or by the remixing paver. Provide and operate equipment in a manner that does not result in physical segregation and limits temperature differentials to less than 35 °F (19.5 °C) throughout the mixture as measured behind the paver and before rolling. Construct a test strip accordin g to 401.08.B to demonstrate the equipment meets these requirements. Use anti-segregation equipment when specified for paving intermediate and surface courses of uniform thickness on all mainline lanes of the traveled way including express lanes, collector - distributor lanes, continuous center turn lanes, acceleration/ deceleration lanes, and ramp lanes.
D.Compaction Equipment. Provide steel wheel or pneumatic tire rollers. Ensure the rollers fully and satisfactorily provide the required compaction, are mechanically sound, and meet asphalt industry standards. The Department retains the right to reject the use of rollers that are not in good repair or are not designed to do the work required. Equip drums and wheels with the necessary accessories to prevent adhesion of the mixture.
401.04 Notification. Notify the Engineer at least 24 hours before starting paving. After starting,
if paving operations stop for 1 week or more, notify the Engineer at least 24 hours before resuming paving.
401.05 Weather Limitations. Place asphalt concrete only if the surface is dry and if weather
conditions are such to ensure proper handling, finishing, and compaction. Never place asphalt concrete if the surface temperature is below the minimum established in Table 401.05-1. Chemical warm mix asphalt (WMA) additives on the Approved List are required for placement in colder temperatures. TABLE 401.05-1 WEATHER LIMITATIONS Course Thickness Minimum Surface Temperature All Mixes[1] Chemical WMA Required[1] 3.0 inches (75 mm) and over [2] 36 F (2 C) 32 F (0 C) 1.5 to 2.9 inches (38 to 74 mm) 40 F (5 C) 32 F (0 C) 1.0 to 1.4 inches (25 to 37 mm) 50 F (10 C) 40 F (5 C) Less than 1.0 inch (25 mm) 60 F (16 C) 50 F (10 C) Variable Intermediate, 0 to 3.0 inches (0 to 75 mm) 40 F (5 C) 32 F (0 C) [1] If used or required, only use chemical WMA additives on the Approved List according to 402.05.B. [2] When paving on an aggregate base or subgrade, use a minimum air temperature of 40 °F (5 °C), or a minimum air temperature of 32 °F (0 °C) when using chemical WMA. In addition to the above surface temperature requirements, do not place surface courses if the air temperature is less than 40 °F (5 °C) without chemical WMA or 32 °F (0 °C) with chemical WMA. For any surface course with a polymer modified asphalt binder, ensure that the paving surface and the air temperature are at least 50 °F (10 °C) without chemical WMA or at least 40 °F (5 °C) with chemical WMA. In addition, for 424 mixes ensure the paving surface and air temperatures are at least 60 °F (15 °C) without chemical WMA or at least 50 °F (10 °C) with chemical WMA. Do not schedule the placement of any surface course with a polymer modified asphalt binder after November 1, regardless of pavement and air temperatures. Obtain the approval of the Engineer to place any surface course with a polymer modified asphalt binder after November 1. Use an approved chemical WMA additive during production, if approved, with the minimum pavement and air temperatures of 40 °F (5 °C). The use of chemical WMA, as described above, may be denied if density acceptance does not achieve at least a pay factor of 1.00.
401.06 Conditioning Existing Surface. Clean the surface on which the asphalt concrete is to be
placed and keep it free of accumulations of materials that would, in the judgment of the Engineer , contaminate the mixture, prevent bonding, or interfere with spreading operations. Where approved subgrade, aggregate, or pavement courses previously constructed under the Contract become loosened, rutted, or otherwise defective, correct the deficiency ac cording to the contract item or items involved before spreading a subsequent pavement course. If placing asphalt concrete against a vertical pavement face, curb, gutter, manhole, or other structure, clean the surface of foreign material and apply a thick, uniform coating of certified 702.01 PG binder,
702.09 Hot Applied Asphaltic Joint Adhesive, or 702.13 SBR Asphalt Emulsion to provide 100 percent
coverage.
401.07 Hauling. Before loading, apply a thin coating of an approved release agent to the inside
surfaces of the truck bed to prevent adhesion of mixture to the bed surfaces. OMM maintains a list of approved release agents. Do not use diesel or fuel oil for this purpose. Any use of non-approved release agent, diesel, or fuel oil may result in suspension of truck, driver, or both for up to one year. Drain truck beds after applying the release agent and before loading. Cover truck beds with the secure, waterproof cover before hauling. At the request of the Engineer , remove bed covers before dumping into the paver. The Engineer may reject loads exhibiting segregation. Obtain OMM approval before making any procedure changes for better mix handling. The Engineer will verify the required temperature of the mixture on arrival at the project site based on the temperature range in the JMF and heat losses in transit. Completely discharge the mixture into the spreading equipment within 90 minutes of loading. Ensure the entire quantity of mixture discharges smoothly into the spreading equipment. Do not clean out truck beds on the roadway ahead of the paver. Provide a location away from the roadway or off the project for cleaning trucks. If there is excessive sticking of material in truck beds, the sticking is in areas of the truck that would indic ate excessive cooling of the mix (front corners, bottom, etc.) due to a long haul, and it is not resolved in a reasonable time, the Engineer will require an insulated bed. Do not exceed a haul distance of 50 miles (80 km) from the asphalt concrete plant to the paving site regardless of prevailing air temperature except by specific permission of the Department.
401.08 Placement Operations. Do not co -mingle multiple JMFs in the same asphalt paver.
Spread the mixture at a rate calculated using the specified thickness and the compacted width of the pavement course being placed, and the weight -to-volume conversion factors established by OMM. If there is not an OMM established rate, the conversion factors in 440.07 apply. Maintain the actual rate of spreading equal to the required calculated rate within the tolerance specified in 401.08.A. For pavement courses specified for leveling, the actual rate of spreading may vary from the required calculated rate as approved by the Engineer to accomplish the intended purpose. Spread the mixture using approved equipment or methods. Preheat screeds and extensions before placing any asphalt concrete. Use side plates sufficient to contain the mixture laterally during spreading. Use only screed extensions, rigid or extendable, having the same features as the main screed including, but not limited to, vibration, heating, pre -strikeoffs, and tamping bars. When using front - mounted hydraulically extendable screeds at a fixed paving width use full width auger extensions and full tunnel ex tensions. When using fixed screed extensions use full width auger extensions and full tunnel extensions. Do not allow a buildup of excess material in front of the screed. Where excessive buildup of material is not controlled, the Engineer will require paver changes to correct the problem. Ensure the paver operation, screed, screed extension, and mix design provide a mat, before compaction, that is free of texture inconsistencies, shadowing, streaking, tearing, pulling, or other deficiencies. Take immediate action to correct the paver operat ion, screed, screed extensions, or mix design. The Engineer may stop placement until corrections are completed. Use strike-off plates/strike-off extensions only on irregular areas such as mailbox turnouts, driveway turnouts, and other irregular non-travelled roadway areas. The Engineer may approve the use of strike- off plates/extensions on variable width shoulders if the use of a standard extendable screed extension with the same features as the main screed is not practicable. Perform supplemental hand forming and tamping where irregularities develop and where placing the mixture by hand methods. Take prompt corrective action if placed mixture exhibits any defect (ex. segregation, tenderness, lack of mixture and texture uniformity, raveling, flushing, rutting, holes, debris, etc.) within the Contractor’s control and as determined by the Engineer. Coordinate the spreading operation with the rate of production and delivery of the mixture to attain uniform, continuous progress. Avoid erratic spreader operation due to irregular contact with the hauling vehicle, surging in the feed, distribution of the mixture, or other cause. Maintain sufficient control of the spreading equipment with regard to line and grade references so that the pavement course, when compacted as specified, is in reasonable conformance with the Contract Documents. Do not displace or damage bridge deck waterproofing membranes during spreading operations on the membranes. Cease the paving operation in the event of equipment breakdown, inability to consistently provide a mat free of physical segregation, inability to consistently meet the temperature differential requirements, or any combination. Do not resume paving until e quipment is replaced with suitable equipment. When anti -segregation equipment is required the Engineer may allow paving to continue if an isolated area of mat temperature differential is in excess of 35 °F (19.5 °C). The Engineer may require additional evaluation of the area to determine the acceptability of the material.
A.Application Rate. If a uniform course is specified, make checks and adjustments to maintain the application rate within a tolerance of ±5 percent of the required calculated weight per unit of area. If a variable depth course is specified, place the mixture as shown on the plans.
B.Anti-Segregation Test Strip . When using anti -segregation equipment, perform a test strip a minimum of 1000 feet (300 m) in length on the first day or night of paving any JMF. Notify the Engineer a minimum of 24 hours before performing the test strip. Demonstrate to the Engineer that the selected equipment is not physically segregating the mix and consistently limits the temperature differential of the mat surface, measured transversely behind the paver and before rolling, to 35 °F (19.5 °C) or less. Document results of each test strip on Department form CA-FP-5. Remove equipment or JMF that provides a mat with physical segregation, does not meet the temperature differential requirement, or both. Perform a new test strip any time placement equipment or JMF is replaced. If the Contractor is unable to produce a satisfactory test strip in two attempts per JMF, cease paving and provide a written plan to the DCA for approval before continuing the paving operation.
C.Night Work. Do not start night work or carry on day work into night work without operating an adequate and approved lighting system. Night work is work performed from 30 minutes after sunset to 30 minutes before sunrise. Operation of adequate lighting system consists of furnishing, installing, operating, maintaining, moving, and removing nighttime lighting to illuminate construction work areas for night work. Obtain the Engineer’s approval of the lighting at the beginning of the project and before starting the paving operation by measuring the luminance. Provide an illuminated zone around all operating machinery. Provide an illuminated zone of at least 5 Foot-candles (55 lux) of lighting luminance in the immediate vicinity of pavers, rollers, grinding equipment, material transfer vehicles, etc., and at lea st 1 Foot-candle (10 lux) at 25 feet (7.6 m) from this equipment. Provide an illuminated zone of at least 5 Foot -candles (55 lux) of lighting luminance in the immediate vicinity of coring equipment and at least 1 Foot -candle (10 lux) at 10 feet (3 m). Position the light sources so they don’t interfere with or impede traffic in any direction and do not cause glare for motorists or point onto adjacent properties. Provide a photometer capable of measuring the level of luminance on each night project. Take lumi nance measurements at a height of 20 inches (500 millimeters) above the roadway. Obtain the luminance level any time requested by the Engineer. Test the illumination levels on the site each time a change in lighting configuration is made. Replace non-functioning lamps immediately. Check the luminaires aiming daily. Clean the luminaires regularly. Correct any deficient lighting within one hour or the Engineer will terminate construction activities. When the total project includes more than one continuous lane mile (including bridges) of surface course paving in combination with night paving and there is no pay item for anti -segregation equipment, provide anti -segregation equipment according to 401.03.C, for only the surface course. Construct a test strip according to 401.08.B. No additional payment will be made for this anti - segregation equipment.
D.Joints. Place the asphalt concrete mixture as continuous as possible. Set up joints at the proper height above the adjacent construction to receive maximum compaction. Where the edge of the new pavement is significantly rounded, trim it to a vertical face before placing the adjacent pavement. On projects where traffic is allowed to cross the edge of the new pavement lane, complete the longitudinal joint of the adjacent lane or shoulder within 24 hours. Construct longitudinal joints using string line or other controls as a point of reference to provide a straight longitudinal joint. Before placing adjacent pavement, trim any locations along the longitudinal joint that deviate horizontally from the point o f reference. Maintain a consistent overlap of 1 to 1 1/2 inches (25 to 38 mm) on adjacent pavement when closing longitudinal joints. Where phasing for maintenance of traffic will not allow lapping cold longitudinal joints according to Standard Construction Drawing BP-3.1, provide a minimum of 6 inches (150 mm) offset between cold joints for each course placed. Form hot longitudinal joints using pavers operating in contiguous lanes, one just ahead of the other. Maintain the distance between pavers in adjacent lanes such that it does not exceed the distance that a normal size load of mixture will cover. Alternate loads of mixture between the pavers. Do not allow rollers performing the initial rolling operation in one lane closer than 12 inches (0.3 m) to the longitudinal joint until the adjacent lane is placed. Inst ead of hot joint construction using multiple pavers, the Contractor may use full width construction with a single unit paver. Seal all cold longitudinal joints by coating the entire face of the cold joint with a certified 702.01 PG binder or 702.09 Hot Applied Asphaltic Joint Adhesive to provide 100 percent coverage of the joint face and extend at least 1/2 inch (13 mm) on both surfaces. Seal all cold transverse construction joints with a certified 702.01 PG binder, 702.09 Hot Applied Asphaltic Joint Adhesive, or 702.13 SBR Asphalt Emulsion to provide 100 percent coverage of the joint; or with a certified 702.04 or 702.12 emulsified asphalt applied at a rate of 0.25 gallon per square yard (1 L/m²). For surface courses, form or cut all transverse construction joints to a vertical before sealing. If placing asphalt concrete against a vertical pavement face, curb, gutter, manhole, or other structure, clean the surface of foreign material and apply a thick, uniform coating of certified 702.01 PG binder, 702.09 Hot Applied Asphaltic Joint Adhesive, or 702.13 SBR Asphalt Emulsion to provide 100 percent coverage. Apply a 2 to 4 inch wide strip of approved 705.04 material or 702.01 approved PG binder at butt joints where a new asphalt surface course meets existing asphalt concrete pavement, including at project limits, drives, and intersections. After completion of the surface course, seal gutters at curbing, median barriers, concrete medians, and traffic islands with certified 702.01 PG binder as directed by the Engineer. Apply the binder at a uniform width of approximately 4 inches (100 mm) and at a rate just sufficient to fill surface voids. The Contractor may open the surface course to traffic before sealing the gutters.
E.Compaction. Unless otherwise directed, begin rolling at the sides and proceed longitudinally parallel to the centerline at a slow, uniform speed. On superelevated curves, begin rolling at the low side and progress toward the high side. After each coverage or complet e round trip, move the roller towards the crown of the road to begin the next pass, overlapping the previous pass by at least one-half the width of the previous pass. Continue rolling until full coverage of the course is complete and all roller marks are eliminated. When constructing a longitudinal joint, roll the joint then follow the applicable rolling procedure. During compaction, take care to prevent displacement of the mat edge and changes to the surface profile. Where displacement or changes occur, correct the area immediately in a manner satisfactory to the Engineer. When constructing a safety edge, operate the rollers in a manner that does not damage or obliterate the tapered edge. Do not roll the taper. Keep drums and wheels properly moistened with water, water containing a detergent, or water containing an approved additive. Do not use excess liquid. Cease production if compaction causes bumps in the mix or the mix is excessively tender. Compact shoulders using the same equipment and procedures as used on the mainline pavement. Along curbs, headers, walls, and in other areas not accessible to rollers, thoroughly compact the mixture with hot, hand tampers or with mechanical tampers. On depressed areas, the Contractor may use trench rollers or rollers fitted with compression strips. Replace mixture that becomes loose, broken, contaminated, or otherwise defective with fresh, hot mixture. Compact it to match with the surrounding area.
401.09 Asphalt Binder Compatibility. If excess fat spots, regular random areas of flushing, or
excess drain down occur on a project that are not attributable to over rolling, plant operation, or mix quality compared to the JMF, the Department will consider the neat asphalt binder incompatibl e with the polymer additive or other mix materials. The Department will reject any on -hand asphalt binder because of incompatibility. The Department will determine if problem areas can be corrected, or if removal and replacement is required. Demonstrate to OMM through testing analysis the compatibility of another asphalt binder and that proper equipment is in place in order to be allowed to resume.
401.10 Surface Tolerances. If a longitudinal profile is specified by elevations on the plans, do
not allow the completed pavement surface to deviate more than 1/2 inch (13 mm) at any point from parallel with the specified profile. Before placing the surface course, check the profile of the preceding course at 50-foot (15 m) intervals along the outside edge of each traffic lane and along any additional line described in superelevation tables, and submit to the Engineer a tabulation of all results that includes documentation of all deviations from the above tolerance. Perform corrective work necessary for compliance with the profile tolerance before placing the surface course. The requirements of this paragraph do not apply to small incidental areas of pavement less than 500 feet (150 m) in length. Do not vary the transverse slope of the surface of any completed course from the specified slope by more than 3/8 inch in 10 feet (10 mm in 3 m). For surface and intermediate courses, do not vary the surface of each completed course from the testing edge of a 10 foot (3 m) rolling straightedge by more than 1/4 inch (6 mm). Furnish straightedges, straightedges equipped with levels, or other devices s uch as approved profilers conforming to Supplement 1058 and using ProVAL software. Obtain the Engineer’s approval of the equipment used. For base courses, do not vary the surface of each completed course from the testing edge of a 10 - foot (3 m) straightedge by more than 3/8 inches (10 mm). If using Asphalt Concrete Base as a subbase for a rigid pavement or base, do not exceed a variation of 1/4 inch (6 mm). Furnish straightedges, straightedges equipped with levels, or other devices satisfactory to the Engineer. Check the surface of each course placed for variations in slope or surface exceeding the tolerances and at locations of suspected bumps when directed by the Engineer. Correct variations in excess of slope or surface tolerance by removing mixture to neat lines and replacing, or by surface grinding in a manner satisfactory to the Engineer.
401.11 Opening to Traffic. Do not allow traffic, including construction traffic, on the compacted
mixture until it has cooled sufficiently to prevent damage. Remove and replace, or otherwise correct in a manner satisfactory to the Engineer , any portion of the pavement course found to be defective in surface texture or composition regardless of whether the defect was identified before or after opening to traffic.
401.12 Method of Measurement. The asphalt concrete pavement thickness shown on the plans
or stated in the Proposal is for calculating the weight required to be placed per unit of surface area. The Contractor is responsible for recording the net weight of each truckload of mixture to the nearest 100 pounds (50 kg) in triplicate on plant ticket forms approved by the Department. If the pay quantities are established by platform scales, provide a tare weight for each truck at the beginning of each day’s operation and a minimum of every 4 hours of operation each day. The Engineer may require additional tare weight measurements at any time. The Engineer will have the right to monitor all weighing operations and may require reweighing trucks at any time or location. Correct any discrepancies immediately. Continued non-compliance will result in the Department taking necessary and appropriate action, such as, but not limited to, assigning a Department ticket writer to the plant. Send one copy of the plant ticket with each load delivered to the paver and present it to the Engineer. The Engineer will convert the total of the weights recorded on the plant tickets representing mixture finished according to contract requirements to cubic yards (cubic meters) using a conversion factor established by OMM. OMM will establish this conversion factor from the approved JMF. If a uniform course is specified, the Department will not pay for cubic yards (cubic meters) that exceed the quantity calculated from plan lines and dimensions.
Referenced in this section
Get an email when 401 changes
Ohio revises spec sections through supplementals and new editions. We check this one every week and email you the day it changes. Free, no account.
Source: Construction and Material Specifications, 2023 (rev. 7/17/2026) Edition. Pages 157–165 of 892. View official source ↗