Section 570 — Polyester Polymer Concrete Overlays for Bridge Decks

BRIDGE DECKS

Description

570.01This work consists of providing, placing, finishing, and curing a PPC overlay system on concrete surfaces.

Material

570.02Conform to the following Subsections: High molecular weight methacrylate 725.18 Polyester polymer concrete aggregate 703.19 Polyester resin binder 725.17 Sand 703.14 Sealants, fillers, and seals 712.01

Construction Requirements

570.03Qualifications. Provide a system provider and system provider technical representative with experience placing PPC overlay systems. A t least 30 days before starting PPC overlay work, s ubmit the following for approval:

(a)System provider. Documentation from the system provider describing experience on at least five projects of similar size and scope within the past 5 years. Include project names, overlay system and quantities, construction dates, locations, and contact information for project owners;

(b)System provider technical representative. A résumé describ ing at least 5 years’ experience with PPC overlay systems and at least five PPC overlay projects within the past 5 years. Include project names, overlay system and quantities, construction dates, locations, and contact information for project owners; and

(c)Contractor experience. Documentation describing at least 5 years’ experience and five completed projects placing PPC overlay systems with similar equipment and scope. Include project names, construction date, overlay system and quantities, construction dates, and contact information for project owners.

570.04Submittals. At least 30 days before the PPC pre -paving meeting, submit the following according to Subsection 104.06:

(a)Operations and placement plan. Include the following:

(1)Schedule of surface preparation, overlay work, and testing;

(2)Staging plan describing surface preparation and overlay placement sequence including:

(a)Asphalt removal methods, and other surface preparation operations;

(b)Paving widths and anticipated paving lengths;

(c)Paving directions with paving from hig h side of bridge to low side. Do not include gaps between passes;

(d)Joint locations placing cold joints within 1 foot of the lane lines or centered within a lane; and

(e)Location of proposed test section.

(3)Method for preventing leakage of primer onto areas of deck that have not rec eived surface preparation; (4) Method for isolating expansion joints including pourable joints at abutment and piers;

(5)Method for measuring and maintaining overlay thickness and profile;

(6)Finishing and texturing plan describing methods that will be used to broadcast sand and saw grooves to produce a skid- resistant surface;

(7)Cure time for polyester concrete;

(8)Storage and handling of HMWM resin and polyester concrete components;

(9)Procedure for disposal of excess HMWM resin, polyester concrete, and containers;

(10)Procedure for cleanup of mixing and placement equipment; and

(11)Proposed schedule for closing and opening lanes during milling, surface preparation, and PPC overlay placement. Include estimated duration of lane closures.

(b)Polyester polymer concrete mix design and overlay system. Include a PPC mix design and overlay system conforming to Subsection 570.06 .

(c)Equipment. Include a list of equipment conforming to Subsection 570.07 .

570.05General. Provide an on -site technical representative for the duration of bridge overlay placement including test strip, surface preparation, application, and cure. 570.06 Composition (Polyester Polymer Concrete Mix Design and Overlay System). Design and produce a PPC mixture consisting of polyester resin and aggregate conforming to Table 570-1. Include a compatible primer with the overlay system. Submit the system provider’s materials information, installation instructions, and independent test results for approval. If recommended by the overlay system provider, use accelerators or inhibitors to achieve proper setting time of the PPC. Verify mix design with trial mixes from proposed sources or with previous PPC production data for the mix design submitted from proposed sources. Verify the performance characteristics shown in Table 570-1. Include the following in each mix design submittal:

(a)Project identification;

(b)Name and address of PPC system provider and suppliers;

(c)Materials proportions;

(d)Name and location of material sources for aggregate, binder resin, polymer, and admixtures;

(e)Type of binder resin proposed. Include content in pounds per cubic yard of mix;

(f)The dry batch mass of the aggregate in pounds per cubic yard of mix;

(g)Dosage of admixtures. Do not mix chemical admixtures together in a mix unless they are compatible. Provide supporting documentation of compatibility from the manufacturers;

(h)Test results from aggregate sieve analysis, absorption, and other specified properties;

(i)Results from tests shown in Table 570-1;

(j)Material certifications; an d

(k)Material samples if requested. Table 570-1

Composition of Polyester Polymer Concrete

PPC Property

Minimum

Bond

Strength ,

ASTM C1583 , pounds per square inch(1) Abrasion Resistance, Caltrans Test 550 or approved equivalent test, maximum weight loss, grams(2) Modulus of

Elasticity ,

Range,

ASTM C469 , pounds per square inch(3) Initial Set Time ASTM C266 , minutes Resin Content, by weight of the dry aggregate , percent 250 < 2 1,000,000 to 2,000,000 30 to 120(4) 12±1

(1)After at least 2 4 hours cure time. Test on in -place material. Drill to at least 0.25 inch but no more than 0.50 inch below the bond line. An acceptable test will demonstrate that the overlay bond strength is sufficient by producing a concrete subsurface failure area greater than 50 percent of the test surface area. Repair bond test locations with polymer overlay.

(2)At 12 percent resin content by weight of dry aggregate. Provide test results that are less than 1 year old.

(3)At 12 percent resin content by weight of dry ag gregate, and after at least 2 4 hours cure time. Provide test results that are less than 1 year old.

(4)Initial set times less than 30 minutes may be proposed by the system provider. Initial set time may also be defined as the point at which the in-place PPC cannot be deformed by pressing with a finger.

570.07Equipment. Provide equipment to be used to prepare the surface, and to mix, place, finish, and cure the PPC. Provide equipment according to the system provider’s recommendations.

(a)Mobile mixing equipment. Keep the equipment maintained, calibrated, clean, and free of partially dried or hardened material.

(1)Use certified scales, with certification less than one month old, to calibrate mobile mixing equipment. Submit sca le certification within 1 month before production. If any adjustments are made to the scales, submit a new certification. Complete on -site calibration by demonstrating that the computer tickets are within 2 percent of the actual material weights. Produce three consecutive batches of aggregate that have batch tickets and actual materials weights that are within 2 percent of each other. Produce three consecutive batches of resin that have batch weights and actual material weights that are within 2 percent of each other.

(2)Use a continuous mixer with the following capabilities:

(a)Employs an auger screw and chute device;

(b)Measures and records aggregate and resin volumes a utomatic ally with a metering device at least every 5 minutes, including time and date. Equipped w ith controls to regulate the quantity of components required to produce the approved mix;

(c)Displays volumes of aggregate and resin on a v isible readout gauge;

(d)Produces a satisfactory mix consistency; and

(e)Measure s the resin levels in the tank of the mobile mixer during paving operations and allows access to the resin tank. A portable mechanical mixer of appropriate size for the proposed batches and recommended by the system provider may be used.

(b)Paving machine. Submit documentation of the proposed paving machine that establishes its successful use to place PPC overlays on bridge projects. Use a self -propelled slip -form paving machine that is modified or built to place PPC overlay and has the follow capabilities:

(1)Employs a vibrating pan to consolidate and finish the PPC, and is fitted with hydraulically controlled grade automation using substrate grade averaging devices on both sides of the new placement to establish the finished profile. Use devices that average 1 5 feet in front and behind the automation sensor s. Use sensors compatible with string -line control;

(2)Equipped with controls capable of maintaining the screed at the specified transverse slope;

(3)Sufficient engine power and weight to provide adequate vibration of the finishing pan while maintaining consiste nt forward placement speed. Capable of forward or reverse motion; and As an alternative to using a paving machine, an approved self -propelled rotating cylinder machine, either single or double roller, that is capable of forward or reverse movement under positive control may be used. Conform to Subs ection 552.12. Equip the machine with an oscillating screed and other devices required to continuously spread, consolidate, and finish the plastic PPC. Ensure the screed extends the full width of the placement.

(c)Other equipment. Include descriptions of equipment used for the following:

(1)Preparing the surface including grinding and shotblasting;

(2)Applying HMWM resin;

(3)Finishing and curing the polyester concrete overlay;

(4)Applying sand;

(5)Texturing and grooving the PPC surface; and

(6)Protecting and finishing inlets and bridge drains.

570.08Production Start -Up Procedures.

(a)Preparatory phase meeting. Conduct a pre -paving preparatory phase meeting according to Subsection 153.06(a) at least 7 days before the start of PPC overlay operations.

(b)Test section. Submit a proposed location of previously constructed concrete to complete a test section. Provide at least 7 days’ notice before placing the test section. Prepare the substrate concrete surface using the same methods intended for the overlay placement. Co nstruct a test section at least 20 feet long at the same thickness and paving width as the overlay. Use the approved mix design and the same methods of handling, placing, finishing, texturing, and curing intended for actual placement. Determine the initial set time. Complete one or more bond strength tests. See Table 570-1 for requirements. Demonstrate the ability to construct an acceptable test section and competency to perform the work. Repeat the test section process until an acceptable test section is produced. If required, remove and dispose of the test section materials off site according to Subsections 203.05 and 203.07. Start production only after the test section is evaluated and accepted.

570.09Surface Preparation. Do not perform surface preparation within 6 feet of a new overlay until 48 hours after its placement.

(a)Removal of asphalt and membrane. Remove asphalt, asphalt membranes, and other deleterious material without damaging the concrete bridge deck. Micro mill according to Section 413 to remove the existing asphalt to a depth ½ inch away from the concrete deck surface. Use other approved methods to remove the remaining asphaltic material. Repair concrete according to Section 572. Do not place PPC until concrete repair material has cured at least 5 days and there is no moisture in the repair areas. Test for moisture in concrete according to ASTM D4263 at locations as directed.

(b)Surface cleaning. Do not start cleaning operations until concrete repairs are complete and the deck is dry. Use equipment and procedures that do not obstruct the view or travel way of motorists in adjacent roadways. Do not power wash. Shot blast to remove grease, oil, asphalt, coating material, membrane, concrete laitance, and other contaminants that could interfere with the proper adhesion of the overlay syste m. Use steel shot conforming to SSPC -AB3 , Ferrous Metallic Abrasive or recycled steel shot conforming to SSPC -AB2 , Cleanliness of Recycled Ferrous Metallic Abrasives. Complete enough passes at a travel speed that results in loose surface concrete being removed, aggregates of the concrete being exposed, and a visible change in concrete color occurring. Capture debris from shotblasting and dispose according to Subsection 203.07. Cover the prepared surface with polyethylene sheeting to prevent contamination. Do not expose cleaned surfaces to traffic. Immediately before placing primer, remove loose particles by oil- free compressed air, magnets, or vacuuming. Make a final complete pass of the area to be overlaid with oil -free compressed air to clean and dry the concrete substrate.

570.10Handling and Storing Material. Prevent segregation, contamination, or other harmful effects during handling and storage of material . Provide aggregate with uniform moisture content at the time of batching. Submit and follow the system provider’ s recommendations.

570.11Delivery. Produce and deliver PPC to allow a continuous placement with no PPC achieving initial set before the remaining PPC being placed adjacent to it. Deliver PPC through the conventional chute of a mobile mixer directly to the paving machine or use another approved delivery process.

570.12Quality Control of Mix. Conform to Subs ection 552.06, except as modified in Table 570-2.

570.13Application of the Polyester Polymer Concrete Overlay. Application methods may be modified according to the system provider’s recommendations and as approved.

(a)Moisture conditions. Do not start placement of HMWM primer and PPC overlay unless the concrete substrate is dry. Do not start placement of the PPC overlay if there is standing water, darkening of substrate surface due to moisture, or evidence of moisture in the substrate cracks. Artificial drying methods , such as usin g oil-free compressed air or a propane torch , may be applied as approved. Do not start placement of HMWM primer and PPC overlay if the relatively humidity is greater than 85 percent or if precipitation is anticipated during the planned production and placement period for the PPC overlay.

(b)Concrete surface temperature. Apply HMWM primer and PPC overlay when the concrete substrate is between 40 °F and 100 °F, unless otherwise recommended by the system provider.

(c)HMWM primer. Apply primer according to the system provider’s recommendations. Mix all components of the HMWM resin. Place primer within 5 minutes of mixing and at a rate of 90 square feet per gallon, or at the rate recommended by the system provider. Uniformly spread primer to completely cover the concre te substrate to be overlaid. Do not allow leakage of primer on unprepared areas and areas that will not receive an overlay. Apply primer with push brooms or rollers. Avoid excess application that results in puddling. Remove excess material to meet the required application rate. Reapply primer to areas that appear dry after 1 5 minutes of absorbing the material.

(d)PPC. Apply PPC within a timeframe of 1 5 minutes to 2 hours after the primer has been applied. Apply PPC before gelling or 15 minutes following addition of initiator, whichever occurs first. Completely blend and initiate the polyester resin binder. Add the aggregate and mix for at least 2 minutes, or as recommended by the system provider. Remove and replace PPC that does not attain an initial set within the range shown in Table 570-1. Consolidate and finish the PPC to the required grade and cross -section. Control the profile and cross- section by a taut reference string line on both sides of the paving machine. Do not start placement operations until the reference elevation and string line are approved. Use the paving machine as the primary finishing device. Hand finish in areas that are inaccessible to the paving machine . Finish to produce a slight resin bleed.

(e)Texturing. Produce a skid resistant surface texture using the following methods:

(1)Sand friction finish. Completely cover the overlay by uniformly broadcasting at least 2.2 pounds per square yard of sand onto the glossy PPC surface immediately after finishing and before resin gelling occurs. Repair smooth or low friction areas from insufficient quantities of sand according to the system provider’s recommendations and as approved.

(2)Grooving. After the bond strength as shown in Table 570-1 is attain ed, groove according to Subsection 552.14(g) . Complete grooving within 7 days of completing PPC overlay placement. Limit traffic speeds to 25 miles per hour or less until grooving is complete. Continuously remove slurry and other residue from the PPC overlay by vacuum pickup or other approved methods. D ispose of slurry and other residue according to Subsection 203.07 .

(f)Joints. Install construction joints and saw cut joint locations as shown in the plans. If no joint locations are shown in the plans, submit a jointing plan for approval. Form the vertical edge at construction joints by bulkhead or saw cut. Make construction joints straight and vertical. If uncontrolled cracking occurs, repair the crack according to the system provider ’s recommendations and as approved. Seal joints according to the system provider’ s recommendations and as approved.

(g)Curing. Protect the overlay from moisture for at least 4 hours. Do not open to traffic until at lea st 4 hours of curing has been completed.

(h)Roughness. Check PPC overlay surfaces with a 10 -foot metal straightedge. Check the entire surface in both the longitudinal and transverse directions with the straightedge. Overlap the straightedge at least one- half of the length of the previous straightedge placement. Defective areas are deviations between the surface and the bottom of the straightedge more than ¼ inch between the two contacts of the straightedge, or deviations more than ¼ inch measured at the end of the straightedge. Correct defective areas. Obtain approval for the method of correction.

(i)Tapers. Complete one lane of PPC placement for the entire length of the bridge in one placement operation. If the need arises to suspend operations and complete a transverse taper, use a bond breaker and construct an asphalt taper with a 1V:10H slope. C ompletely remove the bond breaker and temporary asphalt taper and clean the surface according to Subsection 570.09(b) before resuming PPC placement .

570.14Acceptance. See Table 570-2 for sampling, testing, and acceptance requirements. Material for PCC overlays will be evaluated under Subsections 106.02 and 106.03. Submit a production certification with each shipment of cementitious material. The PPC overlay mix will be evaluated under Subsections 106.02 and 106.04. Construction of PPC overlays for bridge decks will be evaluated under Subsections 106.02 and 106.04. Concrete repairs will be evaluated under Section 572. Micro milling will be evaluated under Section 413.

Measurement

570.15Measure the Section 570 pay items listed in the bid schedule according to Subsection 109.02 .

Payment

570.16The accepted quantities will be paid at the contract price per unit of measurement for the Section 570 pay items listed in the bid schedule. Payment will be full compensation for the work prescribed in this Section. See Subsection 109.05 . Table 570-2 Sampling, Testing, and Acceptance Requirements

Material or

Product

(Subsection) Type of

Acceptance

(Subsection) Characteristic Category Test Methods

Specifications Sampling

Frequency Point of

Sampling Split

Sample Reporting

Time Remarks

Mix Design

PPC

composition Measured & tested for conformance (106.04 & 105) All − Subsection

570.061 per mix design Source of material Yes, if requested 28 days minimum before pre- paving meeting − Production Start -up (Test Section)

PPC Measured &

tested for conformance (106.04 ) Minimum bond strength , psi(1) − ASTM C1583 2 locations per test section minimum In-place after curing is complete No Upon completing tests −

Initial set time ,

minutes − ASTM C266(3) 1 per test section In-place to measure initial set time " " − Table 570- 2 (continued) Sampling, Testing, and Acceptance Requirements

Material or

Product

(Subsection) Type of

Acceptance

(Subsection) Characteristic Category Test Methods

Specifications Sampling

Frequency Point of

Sampling Split

Sample Reporting

Time Remarks

Production

PPC Measured &

tested for conformance (106.04 ) Minimum bond strength , psi(1) − ASTM C1583 1 per 300 yd2 but not less than one per day In-place after curing is complete No Upon completing tests −

Surface

tolerance (roughness) − Subsection 570.13(h) Complete coverage, see

Subsection

570.13(h) Finished

PPC

overlay surface " " −

Process

control (153.03 ) Initial set time , minutes − ASTM C266(3) Continuously during production In-place to measure initial set time No Upon completing tests − Yield(2) − (2) Daily (2) " Before starting the following day’s placement −

(1)After at least 24 hours cure time. Tested on in- place material. Drill from 0.25 inch to 0.50 inch below the bond line. An acceptable test will demonstrate that the overlay bond strength is sufficient by producing a concrete subsurface failure area greater than 50 percent of the test surface area. Repair bond test locations with polymer overlay.

(2)Complete a comparison of the actual yield for each day’s placement to the theoreti cal yield. Theoretical yield is based on the actual area paved and the planned thickness of the mixture being placed. When the variance is greater than 5 percent include a written explanation and corrective measures, as appropriate.

(3)Initial set time may also be defined as the point at which the in -place PPC cannot be deformed by pressing with a finger.