SECTION 536: POLYMER CONCR ETE BRIDGE DECK OVERLAY
536.1 Description
This Work consists of providi ng and applying a polymer concrete Bridge deck overlay.
536.2 Materials
The Contractor shall use epoxy or epoxy urethane from the Depar tment’s Approved Products List. The Contractor shall notify the Project Manager of the selection at least 14 Days before start of Work. The Contractor shall provide Materi als in accordance with Table
536.2 1:1, “Epoxy Physical Requirements” and Table 536.2.1:2, “ Epoxy Urethane Physical
Requirements.”
536.2.1 Epoxy
The Contractor shall provide a two (2) part epoxy, or epoxy ure thane resin base, composed of a 100% solid, thermo setting, moisture-insensitive, flexible, high-elongation compound in accordance with Table 536.2.1:1, “Epoxy Physical Re quirements,” or Table 536.2.1:2, “Epoxy Urethane Physical Requirements.” Table 536.2.1:1 Epoxy Physical Requirements Property Test method Minimum Maximum Remarks Viscosity ASTM D 2393 Brookfield RVT, Spindle #3 @ 20 rpm or ASTM C 881 Seven (7) poises 25 poises — Gel time ASTM C 881, Paragraph 11.2 modified 15 min 45 min — Compressive strength @ three
3.h ASTM C 579 modified (with plastic inserts) 1,000 psi — Mixed with aggregate Compressive strength @ 24 h ASTM C 579 modified (with plastic inserts) 5,000 psi — Mixed with aggregate Tensile strength (neat) @ seven (7) Days ASTM D 638 2,200 psi 5,000 psi — Elongation (neat) @ seven (7) Days ASTM D 638 30% 80% — Adhesive strength @ 24 h ACI 503R, Appendix A, VTM 92 250 psi — Mixed with aggregate with 100% failure in concrete Permeability to chloride ion @ 28 Days AASHTO T 277 — 100 coulombs — Absorption (neat) @ 24 h ASTM D 570 — One percent (1%) — Section 536: Polymer Concrete Bridge Deck Overlay Page 464 Table 536.2.1:1 Epoxy Physical Requirements Property Test method Minimum Maximum Remarks Thermal compatibility ASTM C 884 No delamination of overlay Mixed with aggregate Infrared spectrum AASHTO T 237, Paragraphs 5 and 6 To be established for each component — Table 536.2.1:2 Epoxy Urethane Physical Requirements Property Test method Minimum Maximum Remarks Viscosity ASTM D 2393 Brookfield RVT, Spindle #3 @ 20 rpm 20 poises 70 poises — Gel time ASTM C 881, Paragraph 11.2 modified 15 min 45 min — Compressive strength @ three
3.h ASTM C 579 modified (with plastic inserts) 1,000 psi — Mixed with aggregate Compressive strength @ 24 h ASTM C 579 modified (with plastic inserts) 5,000 psi — Mixed with aggregate Tensile strength (neat) @ seven (7) Days ASTM D 638 2,200 psi 5,000 psi — Elongation (neat) @ seven (7) Days ASTM D 638 30% 100% — Adhesive strength @ 24 h ACI 503R, Appendix A, VTM 92 250 psi — Mixed with aggregate with 100% failure in concrete Permeability to chloride ion @ 28 Days AASHTO T 277 — 100 coulombs — Shore D hardness ASTM D 2240 65 75 — Flexural creep, total movement in seven (7) Days California Test Method 419 0.0065 in — — Flexural yield strength ASTM D 790 5,000 psi — — Absorption (neat) @ 24 h ASTM D 570 — One percent (1%) — Thermal compatibility ASTM C 884 No delamination of overlay Mixed with aggregate Infrared spectrum AASHTO T 237, Paragraphs 5 and 6 To be established for each component —
536.2.2 Submittals
The Contractor shall submit the manufacturer’s recommendations for the proposed Material to the Project Manager 14 Days before use. The Contra ctor shall provide a manufacturer certification verifying the Materials are in accor dance with this Specification. The Contractor shall include a Fourier Transform Infrared Spect rophotometry spectrum in transmittance mode and a bulk sample of each component tested i n the manufacturer’s certification. The Department will maintain confidentiality of the data.
536.2.3 Testing
The Project Manager will Accept the Materials based on the cert ified Laboratory report.
536.2.4 Aggregate
The Contractor shall provide angular grained, stone aggregate f ree of dirt, clay, and Deleterious Material in accordance with Table 536.2.4:1, “Requi red Aggregate Properties,” and Table 536.2.4:2, “Required Aggregate Gradation.” Table 536.2.4:1 Required Aggregate Properties Property Test method Minimum Maximum Remarks Soundness loss, 5 cycles in magnesium sulfate AASHTO T 104 — Eight percent (8%) — Micro-Deval AASHTO T 327 — Ten percent (10%) Aggregate must meet the gradation shown in Table 536.2.4:2, “Required Aggregate Gradation” Moh's hardness — 7 — — Moisture content AASHTO T 255 — 0.2% — Table 536.2.4:2 Required Aggregate Gradation Sieve size % passing Minimum Maximum No. 4 100 — No. 8 15 25 No. 16 0 5 No. 30 0 1 No. 200 0 0.2
536.3 Construction Requirements
536.3.1 Equipment
The Contractor shall only use v ehicles and Equipment that are c lean and do not drip engine fluids, or install drip pans to protect the clean deck a nd overlay.
536.3.1 1 Concrete Surfacing and Cleaning Equipment
The Contractor shall use scabblers, grinding/milling machine, s and blasting, and/or shot blasting. The use of air compressors and/ or vacuum trucks is permitted. The Contractor shall use an air compressor that produces oil-free and moisture-free comp ressed air to remove dust and loose Material from the applicati on surface before applying the prime coat.
536.3.1 2 Placing and Finishing Equipment
536.3.1 2.1 Mechanical Application Equipment
The Contractor shall apply Materials using mechanical metering, mixing and distribution machinery as recommended by the manufacturer of the overlay sys tem. The Contractor shall use an epoxy or epoxy urethane distribution system that complet ely mixes the epoxy or epoxy urethane resin with hardening agent, and provides a uniform dis tribution of the Materials at the required application rate. The use of hand held machine mixing Equipment or hand mixing Equipment is prohibited. The Contractor shall use a self-propelled aggregate spreader th at uniformly applies the dry aggregate at the manufacturer’s recommended application rat e. The Contractor shall use an air compressor that produces oil-fr ee and moisture-free compressed air to remove dust and loose Material from the appli cation surface before applying epoxy or epoxy urethane.
536.3.1 2.2 Hand Application Equipment
The Contractor shall use notched squeegees and brooms that spre ad the epoxy or epoxy urethane Material in accordance with the manufacturer’s require ments. The Contractor shall periodically inspect squeegees duri ng application for wear of t he notch depth, replace any defective squeegees. The Contractor shall use hand tools, as necessary and as approv ed by the Project Manager, for placing aggregate in small areas that are unsuitab le for mechanical spreading. The dry aggregate shall be placed at the minimum rate of ten (1 0) lb per sy or the Manufacturer’s recommended applic ation rate, whichever is great er.
536.3.1 2.3 Vacuum Trucks
The Contractor shall use vacuum trucks that are clean and do no t drip engine fluids, or install drip pans to protect the clean deck and overlay.
536.3.1 2.4 Power Brooms
The Contractor shall use power brooms that are clean and do not drip engine fluids, or install drip pans to protect the clean deck and overlay.
536.3.2 Preapplication
536.3.2 1 Deck Preparation
The Contractor shall complete d eck repairs for patches, delamin ation, and crack filling Section 536: Polymer Concrete Bridge Deck Overlay Page 467 before applying the overlay per Section 533, “Concrete Structur e Repair” and Section 534, “Epoxy Injection” as specified in the Contract. The Contractor shall close and protect deck drains and areas of curb or railing above the proposed surface to ensure epoxy or epoxy urethane and aggregat e does not pass through the drains.
536.3.2 2 Surface Preparation
The Contractor shall prepare the concrete surface per the manuf acturer’s recommendations. In the absence of the manufacturer’s recommen dations, the Contractor shall prepare the concrete surface to produce a surface relief equal to the International Concrete Repair Institute (ICRI) Surface Preparation CSP 5-8, o r ASTM E 965 pavement macrotexture depth from 0.04 inch to 0.10 inch. The Contractor shall provide ICRI concrete surface profile chips to the Project Manager for inspection of prepared surface. ICRI concrete surface profile chips will become the property of the Departmen t.
536.3.2 3 Cleaning
Before placing the overlay, the Contractor shall clean the deck s u r f a c e t o r e m o v e Materials that may interfe re with bonding or curing. The Department will consider cleaning Acceptable when the color of the concrete and mortar changes and coarse aggregate particles are exposed. Cle aning shall open the pores of sound mortar. The Department will consider pavement marking s clean when exposed aggregate shows through the markings. The Contractor shall use a vacuum cleaner or air compressor to remove dust and other loose Material. The Contra ctor shall not use brooms. The Contractor shall obtain Proj ect Manager’s approval of Bridg e deck cleaning and preparation before plac ing the first course.
536.3.3 Safety Provisions
The Contractor shall use personnel certified in the safe handli ng of Materials in accordance with the manufacturer’s requirements. The Contracto r shall submit written documentation of Material handlers’ training to the Project Man ager before applying the overlay.
536.3.4 Storage of Materials
The Contractor shall store Materials in accordance with the man ufacturer’s recommendations.
536.3.5 Usage Limitations
The manufacturer’s application requirements shall govern. If t he manufacturer does not provide guidance on the following items, the following shall ap ply: 1. PCC shall not be less than 28 Days of age at the time of ove rlay; 2. The concrete shall be dry at the time of overlay application . The criteria for “dry” shall be established by: a. ASTM D 4263: for every 500 square feet, an 18 inch x 18 inc h plastic sheet shall be taped to the deck with two (2) inch duct tape. The te st area shall be protected from direct sunlight, direct heat, and damage to the plastic. After 16 Section 536: Polymer Concrete Bridge Deck Overlay Page 468 hours, the concrete shall be considered dry when no moisture ap pears on the bottom of the plastic; and b. It is also Acceptable to use a moisture meter in conformance with ASTM F2659; i. Unless otherwise directed by the manufacturer, the reading s hall be four percent (4%) or less; ii. The meter shall be an electrical impedance moisture meter s pecifically developed and calibrated for the non-destructive measurement of the comparative moisture condition in concrete floor slabs; and iii. The moisture meter shall be used and calibrated in accorda nce with the manufacturer’s written recommendations. The moisture meter manufacturer’s recommendations and the calibration data shall b e provided to the Project Manager for Acceptance prior to use on the project; and 3. The air and deck temperature shall be a minimum of 40 °F at the time of overlay application, and for eight (8) h ours after overlay application. Do not use artificial methods to raise the deck temperature. For new Bridge decks with unventilated stay-in-place forms, in addition to the manufacturer’s application requirements, the Contractor shall n ot install the overlay on PCC that is less than 56 Days of age.
536.3.6 Application
The Contractor shall follow the manufacturer’s application inst ructions. Components A and B shall be applied within the temperature rang e recommended by the manufacturer. Broadcasting on c oncrete shall be performed in a ccordance with the manufacturer’s directions and the method approved by the Projec t Manager. The Contractor shall apply the overlay as two (2) separate appl ications with a total coverage of at least 7.5 gal per 100 ft². The Contractor shall apply the first application of polymer at a rate of at least 2.5 gal per 100 ft². The Contractor shall cover with a minimum of ten (10) pounds of aggregate per square yard, or enough to completely cover the epoxy or epoxy u rethane. The Contractor shall apply the second application of polymer at a rate of at least five (5.0) gal per 100 ft². The Contractor shall cover with at leas t 14 pounds of aggregate per square yard, or enough to completely cover the epoxy or epoxy u rethane. The Contractor shall remove and replace first applications that do not receive enough aggregate before the polymer gels, at no additional cost to the Department. The Department will allow second applications not covered with enough aggregat e to remain in place, but the Contractor must apply additional applications before opening to traffic, at no additional cost to the Department.
536.3.7 Curing
The Contractor shall not allow vehicular traffic or Equipment o n the overlay during the curing period. The Contractor shall cure each application of overlay (polymer and aggregate) free from Section 536: Polymer Concrete Bridge Deck Overlay Page 469 vehicular traffic and until vacuuming or broom does not tear or damage the surface, as determined and approved by the Project Manager. After the first application cures, the Contractor shall remove loose aggregate with a vacuum or broom, prior to the second application.
536.3.8 Expansion Joints
The Contractor shall place expansion joints with bond breakers in Bridge deck expansion joints. The Contractor shall apply polymer over the expansion joints. Within 12 h after application and before opening to traffic, the Contractor shall remove the polymer over the expansion joints using the following procedure: 1. Remove the bond breakers; 2. Score the polymer before gelling; or 3. Saw cut after the cure.
536.3.9 Corrective Work
The Contractor shall correct surface variations that exceed ± 1 /4 inch per three (3) ft, unless otherwise directed by the Project Manager. The Contractor shall repair the damaged overlay areas by saw cu tting in rectangular sections to the top of the concrete deck surface and replacing the Material at no additional cost to the Department.
536.4 Method of Measurement
Epoxy (polymer or urethane polym er) concrete Bridge deck overl ay will be measured by the square yard. Deck repair shall be paid under Section 533, “Concrete Structure Repair” unless noted in the contract as Incidental to Section 536, “Pol ymer Concrete Bridge Deck Overlay.” If an existing overlay must be removed prior to the application of the new overlay, removal shall be paid under Section 601, “Removal of Structures and Obstructions” unless noted in the Contract as Incidental to Section 536, “Polymer Co ncrete Bridge Deck Overlay.”
536.5 Basis of Payment
Pay Item Pay Unit Epoxy Polymer Concrete Bridge Deck Overlay Square Yard Epoxy Urethane Polymer Concrete Bridge Deck Overlay Square Yard
536.5.1 Work Included in Payment
The following Work and item(s) will be considered as included i n the payment and will not be measured or paid for separately: 1. ICRI Concrete surface profile chips; and 2. Surface preparation. Section 537: Polyester/Epoxy Concrete Overlay Page 470 SECTION 537: POLYESTER/EPOXY CONCRETE OVERLAY
537.1 Description
This Work consists of providing and applying polyester/epoxy co ncrete overlay for Bridge deck, approach slab, transition sl ab, and PCCP repairs and/or g rade corrections.
537.2 Materials
The Contractor shall use prime coat and polyester or epoxy resi n binder. The Contractor shall notify the Project Manager of the selection at least 14 D ays before start of Work. The Contractor shall provide Materials in accordance with Table 537 .2.1:1, “Prime Coat Physical Requirements” and Table 537.2.2:1, “Resin Binder Physical Requi rements.”
537.2.1 Prime Coat
For polyester concrete (PPC) the prime coat used with the polym er concrete shall be a wax free, high molecular weight methacrylate resin conforming t o the requirements in Table 537.2.1:1, "Prime Coat Physical Requirements." For epoxy p o l y m e r c o n c r e t e ( E P C ) , the prepared surface shall receive a primer layer of two (2)-co mponent, low modulus epoxy resin conforming to the requirements of Table 537.2.1:1, “Prime Coat Physical Requirements,” or as recommended by the manufacturer. Table 537.2.1:1 Prime Coat Physical Requirements Property Test method Minimum Maximum Remarks Viscosity (PPC) ASTM D 2196 0.25 1.75 poise — Viscosity (EPC) ASTM D 2393 or ASTM C 881 1.5 poise Specific Gravity ASTM D1475 0.90 min — — Flash Point* ASTM D3278 180 F — — * Polyester polymer concrete only The promoter/initiator system for the methacrylate resin shall consist of a metal drier and peroxide. If supplied separately from the resin, the metal dri er shall not be mixed with or allowed to contact the peroxide directly. The Contractor shall not store the containers in a manner that will allow leakage or spillage from one (1) Materia l to contact the container or Material of the other.
537.2.2 Polyester/Epoxy Resin Binder
Polymer concrete shall consist of polyester or epoxy resin bind er. The polyester polymer concrete, the resin shall be an unsaturated isophthalic polyest er-styrene co-polymer and shall conform to the requirements in Table 537.2.2:1, "Resin Binder P hysical Requirements." For epoxy polymer concrete, the resin shall be a two (2)-component, low modulus epoxy polymer conforming to the requirements of Table 537.2.2:1, "Resin Binde r Physical Requirements.” Section 537: Polyester/Epoxy Concrete Overlay Page 471 Table 537.2.2:1 Resin Binder Physical Requirements Property Test method Minimum Maximum Remarks Viscosity ASTM D 2196 0.75 poise 2.0 poise Test before addition of initiator Specific Gravity ASTM D 1475 1.05 1.10 Test before addition of initiator Tensile strength (neat) @ 7 Days ASTM D 638 2,200 psi 5,000 psi — Elongation (neat) @ 7 Days ASTM D 638 35% 80% — Adhesive strength @ 24 h ACI 503R, Appendix A, VTM 92 250 psi — Mixed with aggregate with 100% failure in concrete Absorption (neat) @ 24 h ASTM D 570 — One percent (1%) — Styrene Content ASTM D 2369 40% 50% % mass as volatiles before addition of initiator Infrared spectrum AASHTO T 237, Paragraphs 5 and 6 To be established for each component — The silane coupler shall be an organosilane ester, gammamethac ryloxy- propyltrimethoxysilane. The promoter shall be compatible with suitable methyl ethyl ketone peroxide (MEKP) and cumene hydroperoxide (CHP) initiators.
537.2.3 Aggregate
Aggregate for polyester/epoxy concrete shall conform to the re quirements of Section
509.2 4, “Aggregate,” except the gradation shall meet the follo wing:
Table 537.2.3:1 Polymer Concrete Aggregate Gradation COMBINED AGGREGATE Sieve Size Percentage Passing 3/8 inch Max. No. 4 Max. 1/2 inch 100 100 3/8 inch 83 - 100 100 Section 537: Polyester/Epoxy Concrete Overlay Page 472 Table 537.2.3:1 Polymer Concrete Aggregate Gradation COMBINED AGGREGATE Sieve Size Percentage Passing 3/8 inch Max. No. 4 Max. No. 4 65 - 82 62 - 85 No. 8 45 - 64 45 - 67 No. 16 27 - 48 29 - 50 No. 30 12 - 30 16 - 36 No. 50 6 - 17 5 - 20 No. 100 0 - 7 0 - 7 No. 200 0 – 3 0 – 3 Aggregate retained on the #8 sieve shall have a maximum of 45 percent crushed particles when tested in accordance with AASHTO Test Method T 2 7. Fine aggregate shall consist of natural sand only. Aggregate absorption shall not exceed one percent (1%) as dete rmined by AASHTO Test Methods T 84 and T 85. At the time of mixing with the resin, the moisture content of t he aggregate, as determined by AASHTO Test Method T 255, shall not exceed one half of the a ggregate absorption.
537.2.4 Wear Surface Sand
The sand shall be commercial quality blast sand, conforming to the absorption capacity and moisture content requirements of polyester/epoxy concrete a ggregate of this Specification. The Contractor shall provide sand such that 95% shall pass the No. 8 sieve and 95% shall be retained on the No. 20 sieve.
537.2.5 Submittals
The Contractor shall submit the manufacturer’s recommendations for the proposed Material to the Project Manager 14 Days before use. The Contra ctor shall provide a manufacturer certification verifying the Materials are in accor dance with this Specification. The Contractor shall submit proposed locations of the longitudi nal and transverse joints for approval. The Contractor sha ll not locate the longitudinal joints in wheel lines.
537.3 Construction Requirements
537.3.1 Equipment
537.3.1 1 Concrete Surfacing and Cleaning Equipment
The Contractor shall use scabblers, grinding/milling machine, s and blasting, and/or shot blasting. The use of air compressors and/ or vacuum trucks is permitted. The Contractor shall use an air compressor that produces oil-free and moisture-free comp ressed air to remove dust and Section 537: Polyester/Epoxy Concrete Overlay Page 473 loose Material from the application surface before applying the prime coat. The Contractor shall use vacuum trucks that are clean and do not drip engine f luids, or install drip pans to protect the clean concrete surfaces and overlay.
537.3.1 2 Placing and Finishing Equipment
A continuous mixer, employing an auger screw/chute device, will be approved for use by the Project Manager contingent on a demonstration that the devi ce can consistently produce a satisfactory product. The continuous mixer shall 1) be equippe d with a metering device that automatically measures and records the aggregate volumes and th e corresponding resin volumes, and 2) have a readout gage, visible to the Project Manager at all times, that displays the volumes being recorded. The volumes shall be recorded at n o greater than five (5) minute intervals along with the time and date of each recording. A pr intout of the recording shall be furnished to the Project Manager at the end of each Work shift. The Contractor shall furnish slip-form finishing Equipment with an automatic grade control d evice to strike off the overlay to the established grade and cross section, unless otherwise pre-a pproved by the State Bridge Engineer. The Contractor shall fit finishing Equipment with vi brators or other means of consolidating the overlay Materi al. Finishing machines shall b e self-propelled and capable of forward and reverse movement under positive control. Finishing machines shall be operated normal to the longitudinal Bridge or Roadway centerline. Equipment shall be fitted with suitable traps, filters, drip pa ns, or other devices as necessary to prevent oil or other Deleterious Material from bei ng deposited onto the existing concrete surfaces.
537.3.2 Pre-Application
537.3.2 1 Material Suppliers
The polyester/epoxy concrete overlay system Supplier shall make available a technical representative for a minimum of three (3) Days to make recommen dations to facilitate overlay installation. This shall include, but not be limited to, trial batch preparation, trial overlay placement, surface preparation, o verlay application and overlay cure. The system Supplier shall also provide health and safety traini ng for personnel who are to handle the Materials.
537.3.2 2 Trial Batches and Trial Overlay
The Contractor shall mix one (1) or more trial batches of polye ster/epoxy concrete for various percentages of resin bin der according to manufacturer’s recommendations. The approximate percentage of polyester/epoxy resin binder to use w ill be determined from the trial batches. The Materials, methods, and Equipment used in the trial batches shall be the same as those intended for use in the trial overlay. If at any time di fferent Materials, methods, or Equipment are to be used, new t rial batches will be required. The Contractor shall place one (1) or more trial overlays on a previously constructed concrete base to demonstrate the effectiveness of the proposed mixing, placing, and finishing Equipment. Each trial overlay shall be 12 ft wide, at least si x (6) ft long, and the same thickness as the overlay to be c onstructed. The trial overlay area shall be within the Project limits and at a location approved by the Project Manager. Section 537: Polyester/Epoxy Concrete Overlay Page 474 The Contractor shall remove and dispose of all Materials used i n the trial batches, including the concrete base .
537.3.2 3 Deck Preparation
The Contractor shall complete concrete repairs for patches, del amination, and crack filling per Section 533, “Concrete Structure Repair” as specifi ed in the Contract, before applying the overlay. The Contractor shall use polyester/epoxy concrete as a patching Material. The Contractor shall apply patch Material at least o ne (1) hour before placing the overlay or place the patch Mater ial and overlay monolithically. The Contractor shall close and protect Bridge deck drains and a reas of curb or railing above the proposed surface to ensure that the prime coat, polye ster/epoxy concrete and aggregate do not contaminate these areas. The Contractor shall adequately isolate expansion joints and w eakened plane joints before overlaying or saw them by approved methods within four ( 4) hours after overlay placement.
537.3.2 4 Surface Preparation
The Contractor shall prepare the concrete surface per the manuf acturer’s recommendations. In the absence of the manufacturer’s recommen dations, the Contractor shall prepare the concrete surface to produce a surface relief equal to the International Concrete Repair Institute (ICRI) Surface Preparation CSP 5-8, o r ASTM E 965 pavement macrotexture depth from 0.04 inch to 0.10 inch. The Contractor shall provide ICRI concrete surface profile chips to the Project Manager for inspection of prepared surface. ICRI concrete surface profile chips will become the property of the Departmen t.
537.3.2 5 Cleaning
Before placing the overlay, the Contractor shall clean the conc rete surface to remove Materials that may interfere with bonding or curing. The Contr actor may use a vacuum truck or air compressor to remove dust and other loose Material. The Contractor shall not use brooms or power brooms. The Contractor shall obtain Pr oject Manager’s inspection of con crete cleaning and preparation before placing the prime coat.
537.3.3 Safety Provisions
The Contractor shall use personnel certified in the safe applic ation and handling of Materials in accordance with the manufacturer’s requirements. The Contractor shall provide a soap and water wash station for the workers at the job site. T he Contractor shall submit written documentation of Material applicators’ training to the Project Manager before applying the overlay.
537.3.4 Storage of Materials
The Contractor shall store Materials in accordance with the man ufacturer’s recommendations.
537.3.5 Usage Limitations
Section 537: Polyester/Epoxy Concrete Overlay Page 475 The manufacturer’s application requirements shall govern. If t he manufacturer does not provide guidance on the following items, the following shall ap ply: 1. PCC shall not be less than 28 Days of age at the time of ove rlay; 2. The concrete shall be dry at the time of overlay application . The criteria for “dry” shall be established by: a. ASTM D 4263: for every 500 square feet, an 18 inch x 18 inch plastic sheet shall be taped to the deck with two (2) inch duct tape. The te st area shall be protected from direct sunlight, direct heat, and damage to the plastic. After 16 hours, the concrete shall be considered dry when no moisture ap pears on the bottom of the plastic; b. It is also Acceptable to use a moisture meter in conformance with ASTM F2659; i. Unless otherwise directed by the manufacturer, the reading s hall be four percent (4%) or less; ii. The meter shall be an electrical impedance moisture meter s pecifically developed and calibrated for the non-destructive measurement of the comparative moisture conditi on in concrete floor slabs. iii. The moisture meter shall be used and calibrated in accorda nce with the manufacturer’s written recommendations. The moisture meter manufacturer’s recommendations and the calibration data shall b e provided to the Project Manager for Acceptance prior to use on the Project; and 3. The air and deck temperature shall be a minimum of 40 °F at the time of overlay application, and for eight (8) h ours after overlay application. Do not use artificial methods to raise the deck temperature. For new Bridge decks with unventilated stay-in-place forms, in addition to the manufacturer’s application requirements, the Contractor shall n ot install the overlay on PCC that is less than 56 Days of age.
537.3.6 Application
The Contractor shall follow the manufacturer’s application ins tructions. The prime coat shall be uniformly applied to completely cover the surface to receive the polyester/epoxy concrete. The Contractor shall apply the prime coat at an approximate rate of 0.09 to 0.11 gal/yd 2 or per the manufacturer’s reco mmendations prior to placement o f polyester/epoxy concrete. The Contractor shall flood concrete surfaces with the prime coat, allowing penetration into the concrete and filling of all crack s. The Contractor shall redistribute the applied prime coat in cracks by squeegees or brooms. The q uantity of initiated, promoted resin shall be no more than what is needed to apply a prime coa t. A noticeable increase in viscosity prior to placement will be cause for rejection. If t he primed surface becomes contaminated, or if there is a failure of the Material, the Con tractor shall clean the contaminated or failed area by a brasive blasting and re-prime. Immediately after the prime coat has been applied, the polyeste r/epoxy concrete overlay shall be placed, in accordance with manufacturer’s guidelines. The Contractor shall mix polyester/epoxy concrete in mechanical ly operated mixers. The Contractor shall use a sufficient amount of initiator in the po lyester/epoxy concrete to produce set times between 30 and 120 minutes after placement. Accelerators or inhibitors may be required to achieve proper se t times and shall be used as recom mended by the resin Supplier. Section 537: Polyester/Epoxy Concrete Overlay Page 476 The Contractor shall place and finish polyester/epoxy concrete before gelling or within 15 minutes following addition of the initiator, whichever occurs f irst. The Contractor shall discard polyester/epoxy concrete not placed within this time. The Contractor shall construct longitudinal construction joints parallel to the Roadway alignment only at the submitt ed and approved locations. The Co ntractor shall construct vertical joints perpendicular to the deck surface. The smoothness of the polyester/epoxy concrete surface will be tested with a straightedge. The surface shall not vary by more than 0.02 fee t from the lower edge of a ten
10.foot +/- 0.2 feet long straightedge placed in any directio n . A n y s u r f a c e t h a t f a i l s t o conform to the above tolerance shall be ground to meet this req uirement. The Contractor shall apply abrasive sand finish to polyester/ep oxy concrete surfaces. The Contractor shall apply the s and finish by mechanical means immediately after overlay strike-off. The Contractor shall broadcast sand uniformly onto the surface before gelling occurs at the rate from the manufacturer’s application instruct ions. For polyester concrete Materials, it is Acceptable to tine or groove. For epoxy concrete Materials, grooving is requi red, tining is not allowed. The Contractor shall groove in accordance with Section 512.3.1 0.3, “Grooving of Hardened Concrete.” For tining of polyester concrete Materials, after application of the sand finish and before gelling occurs, the Contractor shall texture the overlay by tin ing with a steel-tined rake with tines 1/8 inch wide and spaced from ¾ inch to 1-1/2 inches apar t. The Contractor shall tine to a depth of 1/8 inch to 3/16 inch. The surface texture of the o verlay shall be uniform and shall have a coefficient of friction not less than 0.35. If the coef ficient of friction is less than 0.35, the Contractor shall additionally groove in accordance with Sec tion 512.3.10.3, “Grooving of Hardened Concrete.”
537.3.7 Curing
The Contractor shall protect the finished overlay from moisture , Equipment, and public traffic until the overlay achieves an average Schmidt hammer re ading of 24. The Schmidt hammer test shall consist of the average of ten (10) readings ( strikes), all taken in an area approximately 18 inches in diameter. The Contractor shall perf orm one (1) such test per 500 sq ft of overlay. Traffic may be allowed on the overlay when t he reading of 24 is achieved. The Contractor shall not contaminate concrete surfaces during c lean-up of tools and Equipment. The Contractor shall not dump or spill polyester/ep oxy concrete Materials or cleaning solvents in areas that w ill cause environmental or fir e hazards.
537.3.8 Reserved
537.3.9 Testing
The Contractor shall provide the necessary Equipment and suppli es for conducting adhesion tests on the completed overlay. The Contractor shall perform adhesion tests according to ACI 503R - Appendix A of the ACI Manual of Concret e Practice. Adhesion tests shall obtain a 250 psi minimum pulloff or cohesive failure with in existing concrete. The Contractor shall perform tests at a frequency of one (1) test p er every 1600 sq ft of deck Section 537: Polyester/Epoxy Concrete Overlay Page 477 surface in a random location. The Contractor shall prime and p atch test holes with polyester/epoxy concrete immediately after testing.
537.3.10 Corrective Work
The Contractor shall correct surface variations that exceed ± 0 .02 ft per ten (10) ft, unless otherwise directed by the Project Manager. The Contractor shall repair damaged overlay areas by saw cuttin g in rectangular sections to the top of the concrete surface and replacing the Material a t no additional cost to the Department. In the event that the testing performed under 537.3.9, "Testing ” does not meet minimum pulloff; the Material shall be removed and replaced in the area s in which low adhesion is determined from additional testing . Any additional testing req uired shall be Incidental to the Work.
537.4 Method of Measurement
Polyester/epoxy concrete will be measured by the cubic yard. T he volume to be paid for will be determined from calculations based on the quantity of r esin binder used, the percent by weight of resin binder in the polyester/epoxy concrete, and a u nit weight of 135 pcf. The Contractor shall furnish suitable measuring devices to assure c orrect proportioning of Materials and accurate measurement for calculating payment quan tities. The payment quantity shall be the calculated quantity of polyester/epoxy co ncrete used in the Work, exclusive of Material used in trial overlay and any wasted or u nused Material. Payment quantity will include patches. The Contract price paid per cubic yard for polyester/epoxy conc rete shall include full compensation for furnishing all labor, Materials, tools, Equipm ent, Incidentals, and for doing all the Work involved in placing polyester/epoxy concrete, includin g furnishing methacrylate resin prime coat and furnishing Materials for trail overlays, removal of unsound concrete and preparation of repair areas when polyester/epoxy concrete is us ed as the patching Material, and as shown on the Plans, as specified in the Standard Specifi cations and as directed by the Project Manager. Removal of loose concrete and preparation of repair areas for p atching Material other than polyester/epoxy concrete will be measured by the square ya rd in accordance with Section 533, “Concrete Structure Repair.”
537.5 Basis of Payment
The Accepted quantities, measured as provided above, will be pa id for at the Contract price per unit of measurement for the pay items listed below th at are shown in the proposal. Payment will be full compensation for the Work described in thi s Section. Pay Item Pay Unit Polyester/Epoxy Concrete Bridge Deck Overlay Cubic Yard
537.5.1 Work Included in Payment
The following Work and item(s) will be considered as included in the payment for polyester/epoxy concrete and will not be measured or paid for s eparately: 1. ICRI concrete surface profile chips; Section 537: Polyester/Epoxy Concrete Overlay Page 478 2. Surface preparation; and 3. Technical representative. Section 540: Steel Reinforcement Page 479
Source: New Mexico Standard Specifications for Highway and Bridge Construction, 2019 Edition. Pages 0–0 of 974.