CATEGORY 500 PAVING HIGH FRICTION SURFACE TREATMENT

Transcription

1 505 HIGH FRICTION SURFACE TREATMENT 1 of 5 CATEGORY 500 PAVING HIGH FRICTION SURFACE TREATMENT DESCRIPTION. Construct a High Friction Surface Treatment (HFST) using Bauxite Aggregate and Polymer Resin Binder at locations as specified or directed. MATERIALS. Provide certification per TC 1.03 at least 30 days prior to construction that the aggregate and binder conform to the specified requirements. All materials must be submitted to the Office of Materials Technology (OMT) for testing at least 45 days prior to construction. All testing must be performed by an accredited laboratory. Polymer Resin Binder. The Polymer Resin Binder shall consist of a two-part thermosetting modified compound that conforms to requirements per PP 79. Deliver one quart each of Part A and Part B of the binder to the OMT s Structural Materials and Pavement Markings Division as specified. Bauxite Aggregate. The material shall be clean, dry, free from foreign matter, and conform to the requirements in Table 1. The sample submitted for testing shall be from the same quarry used for the project. Provide a 55 lb bag of aggregate and one quart each of Part A and Part B of the binder to OMT s Soils and Aggregate Technology Division as specified. Deliver the bauxite to the site in clearly labeled packaging that protects the aggregate from contamination and from exposure to moisture. Table 1 - Aggregate Requirements Test Requirements Test Method Gradation 100% Passing No % minimum Passing No % maximum Passing No. 16 T 27 Apparent Specific Gravity 3.1 minimum T 84 Sodium Sulfate Soundness 12% maximum T 104 LA Abrasion Test 20% maximum T 96 - C grading Moisture Content 0.2% maximum T 255 Aluminum Oxide 87% minimum C 25 Dynamic Friction Value (20 km/hr) 1 Loose aggregate placed last 0.90 minimum on sample with a mean profile depth of 0.9 to 1.4 mm per E E 1911 MSMT 215 MSMT 216 1

2 505 HIGH FRICTION SURFACE TREATMENT 2 of 5 CONSTRUCTION. Qualifications. Provide documentation showing a minimum of three HFST projects on which a cumulative minimum of 10,000 square yards of HFST has been placed within the past three years the projects shall have demonstrated a friction reading of 65 FN40R when tested per T 242. Contractors who do not meet the minimum must be certified by the manufacturer to install HSFT and a manufacturer s representative must be on site during placement. Quality Control (QC) Plan. Submit a QC Plan 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 Quality Control Plan shall contain at a minimum: (a) Key personnel and contact information. (b) Polymer resin production plants, plant locations, personnel qualifications, inspection and record keeping methods, equipment calibration records, accreditation certificates, and minimum frequencies of sampling and testing. (c) Aggregate plant locations, personnel qualifications, inspection and record keeping methods, equipment calibration records, accreditation certificates and minimum frequencies of sampling and testing per Table 2. (d) Methods to control aggregate moisture. (e) All certifications as specified. (f) Procedures for stockpiled and onsite materials storage. (g) Procedures for materials blending and HFST placement. (h) Cleaning and maintenance schedule for Truck Mounted Application Machine. (i) Corrective actions to be taken for unsatisfactory construction practices and deviations from specifications. (j) A manufacturer s representative must be available during application as necessary. (k) Field friction testing after application. 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 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. Weather Restrictions. Do not apply the binder on wet surfaces when the ambient temperature is less than 40 F or above 105 F, or when the anticipated weather conditions or pavement surface temperature would prevent proper application. Condensation moisture on construction vehicles in front of binder applications must be removed prior to placement. Ensure the binder

3 505 HIGH FRICTION SURFACE TREATMENT 3 of 5 components are capable of being mixed at lower than ambient temperatures if the components are stored outdoors. Equipment. (a) Truck Mounted Application Machine. Use an approved self-propelled truck mounted application machine capable of continuously and thoroughly mixing the binder components to the ratio recommended by the manufacturer at a minimum coverage rate of 15 gal/min at varying widths up to 12 feet. The machine must include an aggregate drop spreader capable of continuously spreading bauxite aggregate at a minimum rate of 13 lbs/sy in varying widths of up to 12 feet, with a minimum height from spreader to pavement surface of 24 inches. (b) Regenerative Air Sweeper. Use a self-propelled Regenerative Air Sweeper with power brooms capable of cleaning the existing pavement and removing loose aggregate without dislodging the 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. Preparation. Perform roadway patching per Section 505. Clean and fill all inadequately sealed joints and cracks 1/4 to 1-3/4 in. wide per 510 or 523 with a sealant approved by resin manufacturer. Where HFST will be applied on new asphalt surface in the same project, 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. Remove all existing pavement markings as required per 565. Clean existing surfaces with the sweeper without dust suppression water, or by other methods approved by the manufacturer s representative and the Engineer prior to construction. Surfaces may need to be washed with a mild detergent, rinsed, and then dried using a hot compressed air lance. Receiving surfaces must be clean, dry and free of all dust, oil, debris and any other material that might interfere with the bond between the binder and existing surfaces. Test Section. Select a location then construct a test section a minimum of 200 square yards at a minimum of 24 hours prior to beginning the project to demonstrate equipment has been properly calibrated. 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 additional cost. Mechanical Binder Application. Mix the binder components proportionally in accordance with the manufacturer s recommended ratio. Apply binder at a uniform application thickness of 60 mils onto the pavement section to be treated within the temperature range specified. Do not allow the 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.

4 505 HIGH FRICTION SURFACE TREATMENT 4 of 5 Hand Mixing and Binder Application. Hand application may be used when less than 300 square yards will be used. Mix the binder components to the correct proportion within 4% 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 resulting in a minimum coverage rate of 3.5 square yards per gallon with a uniform thickness of 60 mils onto the pavement. Walking, standing or any form of contact or contamination with the wet uncured binder prior to application of the aggregate without the use of spiked shoes to minimize the disturbance will result in that section being removed and replaced at no cost. Aggregate Application. Apply the aggregate immediately after placing the binder at a uniform rate of lbs 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. The aggregate drop spreader must be used unless less than 300 square yards will be applied in a project, then hand application may be used. Sprinkle or vertically drop the aggregate without splashing the wet film during placement. Sampling and Testing. During construction, sample and test binder and aggregate per Table 1 and PP-79 at a minimum frequency of 1 split set per 2,000 square yards, providing one set to the Engineer or as directed. LA Abrasion, Petrographic Analysis, and Laboratory Dynamic Friction Value tests are waived for Quality Control testing. Sample and label the material under direct observation. Curing and Clean Up. Allow the treatment to cure in accordance the manufacturer recommendations (3 hours max at an ambient temperature of at least 75 o F). Clean up by removing the excess aggregate on the treated area and adjacent areas with raveled aggregate with the sweeper. Perform initial clean up before opening to traffic. Excess Bauxite aggregate can be reused on the following day s installation provided the reclaimed aggregate is clean, dry and uncontaminated. Perform secondary clean up 3 to 5 days after construction. Perform final clean 3 to 5 weeks after construction. Field Acceptance Testing. Ensure the coverage rate of the retained aggregate is lbs per square yard. Remove and re-apply HFST where patches of exposed resin exist at no additional cost. The HFST area will be tested per Table 2 within 60 days after construction. Remove and replace deficient locations as directed. Table 2 Field Acceptance Testing Requirements Property Requirements Frequency FN40R (Corrected field FN by Every 0.1 mile in each lane. By 72 Minimum adding the correction in Table 3) MDSHA Field Dynamic Friction Value 0.90 Minimum 1 per each location, or 1 per every (20 km/hr) (By MDSHA) 1,500 lane-feet, whichever is shorter. By MDSHA Mean Profile Depth (mm) 1.0 Minimum 1 per each location, or 1 per every 1,500 lane-feet, whichever is shorter. By MDSHA Test Method E 274 using a ribbed tire E 1911 E 2157

5 505 HIGH FRICTION SURFACE TREATMENT 5 of 5 Test Speed (mph) Table 3 HFST Speed Correction Factors for E274 Testing FN Test Speed FN Test Speed Correction (mph) Correction (mph) FN Correction MEASUREMENT AND PAYMENT. High Friction Surface will be measured and paid for at the Contract unit price per square yard of accepted work. Payment will be full compensation for furnishing and placing the Polymer Resin binder and aggregate, tie-ins to entrances and connecting roads, test strip, sweeping, sampling and QC testing, cleanup, and for all material, labor, equipment, tools, and incidentals necessary to complete the work. 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. Asphalt Patches will be measured and paid for per Removal of Pavement Markings will be measured and paid for per Section 565. Filling Cracks in Asphalt Pavement will be measured and paid for per Section 510.