for Highway Construction Page 417 of 71 5 SECTION 553 – EPOXY OVERLAY
553.01 Description.
Prepare and apply an epoxy and aggregate overlay on the concrete bridge deck surface area between the curb faces and from the beginning to the end of the bridge and on the approach slabs as specified. S ubmit the following:
1.Submit the name and phone number of the epoxy material manufacturer’s technical representative at the preconstruction meeting.
2.At least 10 calendar days before the epoxy overlay placement , submit:
a.The epoxy materials manufacturer’s written mixing instructions, safety data sheets, independent test re sults, and a certificate of compliance stating the epoxy materials meet the requirements listed in Table 553.02- 1.
b.Independent test results and a certificate of compliance stating the aggregates meet the requirements listed below in Tables 553.02- 2 and 553 .02-4 or in Tables 553.02- 3 and 553.02 -4 and that it is compatible with the epoxy material.
553.02 Materials.
Provide an epoxy resin base and hardener that is a modified Type III, 2-component system that meets the requirements of ASTM C881, Grade 1, Classes B and C. Store the epoxy in accordance with the manufacturer’s specifications. Ensure epoxy properties meet Table 553.02- 1: Table 553.02- 1 – Epoxy Requirements Property Requirement Test Method Gel Time ≥ 15 to ≤ 45 ASTM C881, Paragraph 11.2 modified Tensile Strength (neat) ≥ 2,000 psi to ≤ 5,000 psi at 7 days ASTM D638 Tensile Elongation (neat) ≥ 40% to ≤ 80% at 7 calendar days ASTM D638 Viscosity > 7 to < 25 poises ASTM D2393, Brookfield RVT Spindle No. 3 at 20 rpm Minimum Compressive Strength at 3 hours 1,000 psi at 75 °F ASTM C579 modified (with plastic inserts), mixed with aggregate Minimum Compressive Strength at 24 hours 5,000 psi at 75 °F ASTM C579 modified (with plastic inserts), mixed with aggregate Minimum Adhesion Strength at 24 hours 250 psi at 75 °F ACI 503R, Appendix A, VTM 92 Permeability to chloride ion at 28 days 100 coulombs maximum AASHTO T 277 for Highway Construction Page 418 of 71 5 Pack materials in puncture, rupture, and leak proof containers. Label each container as part A or part B and clearly mark the name and address of the manufacturer, name of the product, mixing proportions and instructions, lot and batch numbers, date of manufacture, and quantity . Provide aggregate topping that is clean, dry, and without deleterious matter. Ensure the aggregate is compatible with the epoxy material. Furnish aggregates in appropriate packaging that is clearly labeled (i.e., showing the name of the manufacturer and location of processing) and protects the aggregate from contaminates, rain, and other m oisture. Provide aggregate as specified and that meets the properties in Tables 553.02- 2 or 553.02 -4. If aggregate is not specified, either aggregate is acceptable. Provide an aggregate with gradation that meets the requirements in Table 553.02- 3 or 553.02- 5, as appropriate . Table 553.02- 2 – Calcined Bauxite Aggregate Requirements Property Requirement Test Method Resistance to Degradation – LA Abrasion Test 20% maximum AASHTO T 96 or ASTM C131 “D” Grading Resistance to Degradation – Micro -Deval Abrasion Test 5% maximum AASHTO T 327 or ASTM D6928 Moisture Content 0.2% maximum AASHTO T 255 Aluminum Oxide 87% minimum ASTM C25 Mohs Scale Hardness 8 minimum ------ Table 553.02 -3 – Calcined Bauxite Aggregate Gradation Requirements Sieve Size Total Percent Passing No. 4 100 No. 6 95 – 100 No. 16 0 – 5 Table 553.02-4 – Standard Aggregate Requirements Properties Requirement Test Method Resistance to Degradation – LA Abrasion Test 20% maximum AASHTO T 96 or ASTM C131, “D” Grading Resistance to Degradation – Micro -Deval Abrasion T est 10% maximum AASHTO T 327 or ASTM D6928 Moisture Content 0.2% maximum AASHTO T 255 Mohs Scale Hardness 7 minimum ------ for Highway Construction Page 419 of 71 5 Table 553.02 -5 - Standard Aggregate Gradation Requirements Sieve Size Total Percent Passing No. 4 100 No. 10 10-35 No. 20 0-10
553.03 Construction Requirements
Ensure the epoxy overlay manufacturer‘s representative is on the project site at all times and who, upon consultation with the Engineer, may suspend work items that do not meet specification requirements. Work may resume only after taking appropriate remedial action to satisfy the manufacturer’s representative and the Engineer. Plan and perform the work to allocate the specified minimum curing periods, or other longer curing periods prescribed by the manufacturer, before opening to public or construction traffic.
A.Equipment. For mechanical applications, provide equipment with at least an epoxy distribution system, aggregate spreader, application squeegee, moisture and oil -free compressed air, and a source of lighting if work will be performed at night. Ensure the epoxy distribution system accurately blends the epoxy materials in accordance with the manufacturer’s written specifications and distributes epoxy at the specified application rates to cover 100 percent of the work area. Propel aggregate spreader to uniformly and accurately apply the aggregate. For manual applications, provide equipment with calibrated containers for measuring epoxy volumes, a paddle- type mixer , squeegees, shovels, and brooms that are suitable for mixing the epoxy and applying the epoxy and aggregate at the specified application rates.
B.Preparation of Concret e Surfaces. Repair minor potholes and delamination in the dec k surface by removing the damaged concrete and patching with an Engineer -approved cementitious patching material before installation of the overlay. Epoxy overlay material is an acceptable alternate patching material. Strike off patches so they are level with the existing deck and finish with wooden floats. Portland cement concrete patches require a minimum cure period of 28 calendar days before application of the overlay. Before placing the overlay, oblit erate all pavement markings and thoroughly clean the entire concrete deck by steel shot blasting to ensur e proper bonding between the epoxy and the concrete substrate. Achieve a final surface texture meeting numbers 5 through 7 as defined in ICRI Guideline No. 03732 and as shown by surface profile samples available from ICRI, or ASTM E965 pavement macrotexture depth of 0.04 to 0.08 inches. Shot blasting is meant to expose the coarse aggregate and ensure the surface is cleaned of asphalt material, oil, dirt, rubber, curing compounds, paint carbonation, laitance, weak surface mortar, and other potentially detrimental materials, which may interfere with the bonding, or curing of the overlay. Remove and repair loosely bonded patches and remove pavement markings. Use moisture and oil -free compressed air or high volume leaf blowers to remove dust that adheres to the prepared surface. To determine the adequacy of the surface preparation, perform at least 1 bond test per lane of each bridge. For each test, apply palm -sized patties of binder aggregate , ¼ to 3/8 inch thick at 3 locations. After the samples have cured, remove the patties with a hammer, and chisel to examine the fracture and delamination for Highway Construction Page 420 of 71 5 plane. Verify concrete with fractured aggregate has attached to the entire underside of the patty. If only lattice or small particles of concrete are attached, further deck preparation is required.
C.Overlay Application. Handle and mix the epoxy resin and hardening agent in a safe manner to achieve the desired results in accordance with the specifications and the manufacturer's written instructions. Only apply epoxy overlay materials when weather or surface conditions allow the material to be properly handled, placed, and cured within the specified requirements for project sequencing, traffic control, or when rain is not imminent within the manufacturer’s recommended cure times. Completely dry the prepared surface when applying epoxy. The Engineer may allow moisture and oil -free heat sources or torches to dry the surface. Ensure the temperature of the deck surface, epoxy, and aggregate components are at least 55 °F and rising at the time of application. Do not apply epoxy if the gel time is less than 5 minutes or if deck surface temperatures exceed 115 °F. In situations where road closures are not under strict time constraints, obtain the Engineer’ s approval to apply epoxy at lower temperatures. Apply the epoxy overlay and aggregate using a double pass method. The double pass method applies the epoxy and aggregate in 2 separate layers at the corresponding application rates specified in Table 553.03- 1. Table 553.03- 1 – Double Pass Method – Epoxy & Aggregate Application Rates Double Pass Method Estimated Epoxy Rate – gal/yd2 Aggregate – lb/yd2 (a) 1st cour se 0.22 10 2nd course 0.45 14.5
a.Application of aggregate must be of sufficient quantity to completely cover the epoxy . Mix the epoxy at a volume ratio of 1 part A to 1 part B and mechanically stir with a paddle- type mixer for 3 minutes or according to the epoxy manufacturer’s written instructions. After the epoxy has been properly mixed, immediately and uniformly apply to the pavement surfa ce with a 3/16 to ¼ inch V -notched squeegee. Apply the aggregate to cover the epoxy material while the epoxy material while the epoxy is still fluid. Remove and replace first course applications that do not receive enough aggregate before gelling. Ensure each course of epoxy overlay cures before removing the excess unbonded aggregate to prevent tearing or damaging of the surface. Use moisture and oil -free compressed air, high -volume leaf blowers, or vacuum broom to remove excess aggregate. After loose aggregate is removed, remove remaining dust using moisture and oil -free compressed air, high- volume leaf blowers, or vacuum broom. Obtain the Engineer’s approval before opening the first course to traffic. Begin application of the second course only after removing dust. The Department prohibits traffic on the overlay until it has cured sufficiently to prevent damage from wheel loads as specified in Table 553.03- 2. Table 5 53.03 -2 – Typical Curing Times Average Temperature of Deck, Epoxy, and Aggregate Components in °F Course 60-64 65-69 70-74 75-79 80-84 Above 85 (a) 1 4 hr 3 hr 2.5 hr 2 hr 1.5 hr 1 hr 2 6.5 hr 5 hr 4 hr 3 hr 3 hr less than 3 hr for Highway Construction Page 421 of 715 (a) Refer to manufacturer’s written instructions. Apply the second course at the rates specified in Table 553.03- 1. Apply epoxy to ensure the wet epoxy does not coat the wear (top) surface of the aggregate. Once the epoxy is cured, remove loose aggregate from the surface with moisture and oil -free compressed air, high volume leaf blowers, or vacuum broom. After removing loose aggregate, if there are a ny areas where epoxy has coated the top surface stone, remove the excess epoxy using a light shot or sandblast. Protect the bridge deck expansion joints with a bond breaker (e.g., duct tape) that can adequat ely seal the joints from the epoxy . The Contractor may also use duct tape to delineate application areas. The Department recommends taped areas or bond breakers be removed before epoxy starts to harden. The Contractor may also remove epoxy by scoring the overlay before gelling or by saw cutting after cure. Feather the overlay out at the end of the bridge or approach slab and at expansion joints (edge of armor angle) in accordance with the manufacturer’s w ritten instructions. If the Contractor' s operations or actions damage or mar the overlay, remove the damaged areas and reapply the overlay to the Engineer’s satisfaction. In the event that part of the epoxy mixture does not cure, completely remove the overlay from the affected area and discard. Completely remove residual epoxy remaining on the pavement by mechanical means (e.g., steel shot, abrasive blasting, scarifying) before reapplying the overlay. Maintain and provide records for each batch provided, including:
1.Number of batches mixed and volume per batch.
2.Location of batches as placed on deck , referenced by stations.
3.Batch time.
4.Gel time (50 milliliter sample).
5.Temperature of the air, deck surface, and epoxy components.
6.Loose aggregate removal time.
7.Time open to traffic.
553.04 Method of Measurement.
The Engineer will measure acceptably completed work by the square foot of deck surface.
553.05 Basis o f Payment .
The Department will pay for accepted quantities at the contract unit price as follows: Pay Item Pay Unit Epoxy Overlay ....................................................................................... SF Surface preparation, inclu ding obliteration of pavement markings, is incidental . Patch and repair of concrete will be paid under 582. 554-559 for Highway Construction Page 422 of 715 SECTIONS 554 -559 - RESERVED for Highway Construction Page 423 of 71 5 SECTION 560 – DEWATERING FOUNDATION
560.01 Description.
Provide, install, maintain, and remove dewatering system necessary for removing and/or diverting water around foundations to allow excavation, pile installa tion, construction of footings, columns, and riprap placement as specified or as directed. Water removal may be accomplished by draining, pumping, bailing, stream diversion, construction of cribbing, or cofferdams. Earthen cofferdams are not allowed .
A.Submittals.
1.Submit the materials, installation, maintenance, and removal information of the dewatering system for approval as specified in 105.02. Submit a dewatering plan including drawings and written descriptions of the proposed procedures for dewatering, pumping, and disposal of fluidiz ed materials.
2.Design temporary retaining structures that meet the most recent AASHTO Guide Specifications for Bridge Temporary Works. Calculations for the proposed configuration of the dewatering system must be signed and sealed by an Idaho licensed professional engineer.
560.02 Materials.
Not specified.
560.03 Construction Requirements.
Secure and comply with all permits and Idaho Department of Water Resources requirements for this work as specified in 107.02. Meet the environmental protection requirements as specified in 107.17. Construct as specified in 210 and 501.03. Select and design a dewatering system that isolates anticipated stream flows from construction areas. Ensure the dewatering method will accommodate seal concrete placement to the elevations specified. Vent cofferdam walls to prevent excessive hydrostatic pressure from developing below the seal concrete during probable flooding at the time of construction. Any suspended sediment and turbidity resulting from streambed dewatering activities must not violate applicable in- stream turbidity criteria. Once the dewatering system is installed, in- stream turbidity levels must not exceed ambient background water quali ty for the duration of use. All sediment and erosion control measures must be in place before the commencement of the dewatering system construction. Maintain a safe, clean, and accessible project site and repair any damage caused by failure of the dewatering system. Provide adequate clearances in all directions as required for the execution of the work to be performed in the dewatered area. This must include room for the dewatering pumps, installation, and removal operations.
A.Seal Concrete. Place seal concrete within the dewatered area at the pier after pile driving is completed and accepted. Place seal concrete as specified in the applicable provisions of 502.03. Before dewatering, cure the seal concrete at least 3 calendar days and until concrete reaches minimum compressive strength of 2,500 psi.
Source: Idaho Standard Specifications for Highway Construction, 2023 Edition. Pages 453–458 of 768.