514High Friction Surface Treatment

— HIGH FRICTION SURFACE TREATMENT [Spec Year] STANDARD SPECIFICATIONS FOR CONSTRUCTION AND MATERIALS CATEGORY 500 PAVING

514.01DESCRIPTION

Construct a High Friction Surface Treatment (HFST) using calcined bauxite aggregate and polymeric resin binder at locations as specified or directed.

514.02MATERIALS

High Friction Surface Treatment Section 928

514.03CONSTRUCTION

Provide certification per TC 1.03 at least 30 days prior to construction that the aggregate and binder conform to the specified requirements.

.01 Qualifications. Provide documentation showing a minimum of three HFST projects

on which a cumulative minimum of 5000 yd2 of HFST has been placed within the past three years using calcined bauxite, excluding bridge decks. The projects shall have demonstrated a friction reading of 65 FN40R when tested per E 274, or Dynamic Friction Value of 0.7 per E 1911 at 20 km/hr. Contractors who do not meet the minimum must be certified by the polymeric resin binder manufacturer to install HFST.

.02 Application Quality Control (QC) Plan. Submit a QC Plan for Application and

provide a copy to the OMT for approval at least 45 days prior to placement. The QC Plan shall show proposed methods to control the equipment, materials, mixing, and paving operations to ensure conformance with the specifications. Discuss the QC Plan requirements at the pre- construction, pre-pave, and progress meetings. The QC Plan shall contain at a minimum:

inspection and record keeping methods, equipment calibration records, accreditation certificates, and minimum frequencies of sampling and testing.

qualifications, inspection and record keeping methods, equipment calibration records, accreditation certificates and minimum frequencies of sampling and testing per the Soils 680 — HIGH FRICTION SURFACE TREATMENT [Spec Year] STANDARD SPECIFICATIONS FOR CONSTRUCTION AND MATERIALS and Aggregates Testing Division (SATD) QA Manual (Frequency Guide, https://roads.maryland.gov/OMT/QAM-SATD.pdf) and Table 928B.

from specifications. Record of issues encountered in the last three years and remedial actions that were implemented.

application as necessary.

plastic stage.

The QC Plan shall designate a Plan Administrator who shall have full authority to institute any action necessary for the successful operation of the Plan. The Plan Administrator may supervise the QC plan on more than one project, if that person can be in contact with the job site within one hour after being notified of a concern. A field technician provided by the contractor shall be present at the job site unless otherwise approved in the QC Plan. The technician shall be responsible for the required field quality control sampling and testing in conformance with the approved quality control plan and contract documents. Maintain and make available upon request complete records of sampling, testing, actions taken to correct problems, and quality control inspection results. Any deviation from the approved QC Plan shall be cause for immediate suspension of operations.

.03 Weather Restrictions. The pavement must be dry. Do not apply the binder on wet

surfaces or when the anticipated weather conditions or pavement surface temperature would prevent proper application. Condensation moisture from construction vehicles in front of binder applications must be removed prior to placement. Do not apply the binder when the ambient and pavement temperatures are less than 40 F. 681 — HIGH FRICTION SURFACE TREATMENT [Spec Year] STANDARD SPECIFICATIONS FOR CONSTRUCTION AND MATERIALS

.04 Equipment

approved self-propelled truck mounted application machine capable of continuously and thoroughly mixing the binder components to the ratio recommended by the manufacturer and applying at a minimum coverage rate of 15 gal/min at varying widths up to 12 ft. The applicator vehicle shall mechanically mix, meter, monitor, and apply the binder resin system and spread the aggregate a minimum of 12 ft wide in one uniform and continuous pass. The aggregate should be spread at a rate of 12 lb/sy to 16 lb/sy in varying widths of up to 12 ft with a maximum height from spreader to pavement surface of 12 in. If recommended by the manufacturer, metering pumps shall be heated.

power brooms capable of cleaning the existing pavement and removing loose aggregate without dislodging the aggregate. If it is desired to re-use loose aggregate, the sweeper must be capable of recycling loose aggregate into clean, uncontaminated, and dry aggregate. The sweeper must be capable of being used without water for dust suppression to ensure a dry surface will be maintained.

.05 Preparation. Perform roadway patching as specified in Section 505. Clean and fill all

inadequately sealed joints and cracks 1/4 in. to 1-3/4 in. wide as specified in Section 510 or Section 523 with a sealant approved by resin manufacturer. Where HFST will be applied on new asphalt surface in the same location, construct HFST a minimum of 30 days after placement of underlying and adjacent pavement. Completely remove all curing compounds on new Portland cement concrete surfaces prior to installation. Adequately cover and protect all utilities and existing pavement markings in areas where markings will be left in place prior to HFST placement or remove all existing pavement markings as specified in Section 558. On Portland cement concrete pavement, perform surface abrasion as specified in Section 512 prior to installation. On all pavement surfaces, clean existing surfaces with a sweeper without dust suppression water, or by methods approved by the manufacturer’s representative and the Engineer prior to construction. Clean asphalt pavement surfaces using mechanical sweepers and high-pressure air wash with sufficient oil traps. Mechanically sweep all surfaces to remove dirt, loose aggregate, debris, and deleterious material. Vacuum sweep or air wash, using a minimum of 180 ft 3/minute and 80 lb/in 2 of clean and dry compressed air, all surfaces to remove all dust, debris, and deleterious material. Wash pavement surfaces with a mild detergent solution to remove all dust, oil, grease, debris and any other material that might interfere with the bond between the polymeric resin binder and existing surfaces, and dry using a hot compressed air lance.

.06 Test Section. Select a location and construct a test section a minimum of 200 yd 2 at a

minimum of 24 hours prior to beginning the project to demonstrate equipment has been properly calibrated, and appropriate application procedures have been established. If the project site is used for the test section, open the test section to traffic after curing has completed and no uncovered binder remains exposed. Correct deficient areas before opening to traffic as directed at no 682 — HIGH FRICTION SURFACE TREATMENT [Spec Year] STANDARD SPECIFICATIONS FOR CONSTRUCTION AND MATERIALS additional cost. Approval of the Test Section must be granted by the engineer prior to subsequent placement.

.07 Binder Application. Measure and record the surface temperature of the pavement

Mix the binder components proportionally in accordance with the manufacturer’s recommended ratio. Apply mixed binder at a uniform application thickness of 60 ± 5 mils onto the pavement section to be treated, within the pavement surface temperature range specified by the binder manufacturer. Measure the binder thickness using a global wet film thickness gauge every 200 ft. Do not allow the mixed binder to separate in the mixing lines, cure, dry, chill, set up, or otherwise impair retention bonding of the high friction surfacing aggregate. Ensure that no seams are visible in the middle of the traffic lanes after application of the surface aggregate.

.08 Aggregate Application. Immediately after placing the binder, apply the aggregate at a

uniform rate of 12 lb -16 lb. per square yard. Completely cover the wet binder with aggregate to achieve a uniform surface with no exposed binder remaining visible on the surface prior to gelling. The binder shall not be exposed for more than 5 minutes, or half of the polymeric resin binder working time relative to the pavement temperature at the time of placement, whichever is shorter. Sprinkle or vertically drop the aggregate without splashing the wet film during placement. Spread the aggregate without displacing the wet binder film during placement.

.09 Manual Application. Manual application may be used when less than 300 yd2 will be

used. Mix the binder components to the correct proportion within 4 percent by weight using a low-speed high torque drill fitted with a helical stirrer. Hand-apply the mixed components onto a prepared pavement surface using a serrated edged squeegee. Use spiked shoes to minimize the contamination or disturbance of applied binder. Avoid contact or contamination of the wet uncured binder prior to application of the aggregate. Remove and replace damaged, contacted or contaminated sections at no cost. The aggregate may be applied manually.

.10 Semi-Automated Application. Semi-Automated application may be used when less

than 2000 yd2will be used, and consists of machine mixing of binder, hand squeegee work to apply mixed binder, and machine application of aggregate. Use equipment to continuously mix, meter, and monitor the binder. If recommended by the binder manufacturer, use a heated metering pump. Mix the binder according to the manufacturer’s specifications (± 2 percent by volume). Immediately after the binder application, use a serrated squeegee to distribute a uniform binder thickness. Mechanically apply the aggregate immediately after placing the binder. Manually spreading the aggregate is allowed as a secondary method if the mechanized equipment cannot physically be used.

.11 Automated Application. Automated application consists of machine mixing and

application of binder, and machine application of aggregate. No hand squeegee work is allowed. The aggregate drop spreader must be used.

.12 Sampling and Testing. During construction, sample and test binder and aggregate per

Table 928A and Table 928B at the start of the project and at a minimum frequency of 1 split set per new lot/batch thereafter, providing one set to the Engineer or as directed. Laboratory Dynamic 683 — HIGH FRICTION SURFACE TREATMENT [Spec Year] STANDARD SPECIFICATIONS FOR CONSTRUCTION AND MATERIALS Friction Value testing is waived for Quality Control testing. Sample and label the material under direct observation.

.13 Curing and Clean Up. Allow the treatment to cure in accordance the manufacturer

recommendations. Clean up by removing the excess aggregate on the treated area and adjacent areas with raveled aggregate with the regenerative air sweeper. Perform initial clean up before opening to traffic. Excess aggregate can be reused on the following day’s installation provided the reclaimed aggregate is clean, dry, and uncontaminated. Recovered aggregate may only be reused once and must be blended with new aggregate at a rate of 2:1 (two parts new aggregate to one part recovered aggregate). Perform secondary cleanup 3 days to 5 days after construction. Perform final cleanup 3 weeks to 5 weeks after construction. Where pavement markings are required to be placed on HFST, use temporary pavement markings until final cleanup is performed. Apply final pavement markings after final clean up.

.09 Manual Application. After the second aggregate sweeping as specified in 514.03.13,

remove and re-apply HFST to areas with bare asphalt or concrete pavement, areas with binder material only, and areas with poor aggregate retention at no additional cost. Contact the Office of Materials Technology to schedule field acceptance testing per Table 514Aafter final clean up and within 60 days after construction. Optionally perform FN40R Quality Control testing per Table 514A under the engineer’s supervision and submit for approval. OMT will conduct the testing per Table 514A, whether or not the contractor performs optional testing. Remove and replace polymeric resin binder and aggregate at deficient locations as directed and per Table 514C. TABLE 514A FIELD ACCEPTANCE TESTING REQUIREMENTS PROPERTY REQUIREMENTS FREQUENCY TEST METHOD FN40R (Corrected field FN by adding the correction in Table 514B) Refer to Table 514C Every 0.1 mile in each lane. By SHA E 274 using a ribbed tire Mean Profile Depth (inches) 0.04 Minimum Every 0.1 mile in each lane. By SHA E 1845 684 — HIGH FRICTION SURFACE TREATMENT [Spec Year] STANDARD SPECIFICATIONS FOR CONSTRUCTION AND MATERIALS TABLE 514B HFST SPEED CORRECTION FACTORS FOR E 274 TESTING Test Speed (mph) FN Correction Test Speed (mph) FN Correction Test Speed (mph) FN Correction 20 -6.7 30 -3.3 40 0.0 21 -6.3 31 -3.0 41 0.3 22 -6.0 32 -2.7 42 0.7 23 -5.7 33 -2.3 43 1.0 24 -5.3 34 -2.0 44 1.3 25 -5.0 35 -1.7 45 1.7 26 -4.7 36 -1.3 46 2.0 27 -4.3 37 -1.0 47 2.3 28 -4.0 38 -0.7 48 2.7 29 -3.7 39 -0.3 49 3.0 TABLE 514C ACCEPTANCE AND PAYMENT FACTOR PER HFST SITE Average FN40R (per HFST Site) HFST Acceptance Item Pay Factor (%) (added to initial 50% payment) ≥ 72 Yes 50 65 to < 72 Yes 40 < 65 No Remove and replace, or reapply, at no additional cost to the Administration to obtain acceptable FN40R. Manufacturer’s technical representative must approve any proposed reapplication treatments and be present during all corrective work. Engineer must approve all corrective work plans before implementation. If Average FN40R values are at 65 or higher after reapplication, payment per the first two rows of this table shall apply.

514.04MEASUREMENT AND PAYMENT

High Friction Surface will be measured and paid for at the Contract unit price per square yard. 50 percent of the payment will occur after placement. If performing optional QC testing, the next 25 percent shall be paid if the Average FN40R is at least 65. The remaining shall be paid after Field Acceptance Testing is complete per 514.03.14 and Table 514C, or if OMT does not perform the Field Acceptance Testing per the timelines in 514.03 14. The payment will be full compensation for furnishing and placing the polymeric resin binder and aggregate, tie-ins to entrances and connecting roads, test section, sweeping, sampling and Quality Control testing, Quality Control plan, clean up, and for all material, labor, equipment, tools, and incidentals necessary to complete the work. 685 — HIGH FRICTION SURFACE TREATMENT [Spec Year] STANDARD SPECIFICATIONS FOR CONSTRUCTION AND MATERIALS No deduction will be made for the areas occupied by manholes, inlets, drainage structures, pavement markings, or by any public utility appurtenances within the area. Material placed outside of the designated treatment area will not be included in computing the quantity.

.01 Asphalt Patches will be measured and paid for as specified in 505.04

.02 Removal of Pavement Markings will be measured and paid for as specified in

Section 558.

.03 Filling Cracks in Asphalt Pavement will be measured and paid for as specified in

Section 510.

.04 Surface Abrasion on Portland Cement Concrete Surface will be measured and paid for

as specified in Section 512. 686