DAMPPROOFING , WATERPROOFING , SEALING , AND MEMBRANES DESCRIPTION
646.01.01 General. This work consists of bridge deck preparation and furnishing and applying dampproofing,
waterproofing, sealant s, and membrane materials to concrete and masonry elements . MATERIALS
646.02.01 Dampproofing and Waterproofing. Primer shall conform to ASTM D41.
Asphalt shall conform to ASTM D449, Type I for below ground and Type III for above ground, except that the ductility for Type III shall be 5 minimum. Glass f abric for waterproofing shall conform to ASTM D1668.
646.02.02 Crack Sealant. Manufacturers of crack sealants are listed in the QPL.
646.02.03 Surface Sealant. Manufacturers of surface sealants are listed in the QPL.
646.02.04 Sheet Membrane. Manufacturers of sheet membrane s are listed in the QPL.
646.02.05 Liquid Membrane. Manufacturers of liquid membrane s are listed in the QPL.
CONSTRUCTION
646.03.01 Dampproofing. Make concrete surfaces smooth and free of depressions and projections which
might damage the dampproofing. The surface shall be dry and cleaned of dust and loose materials. Do not apply primer or asphalt in wet weather, nor when the surface temperature is either below 4 °C (40 °F) or below that recommended by the manufacturer. Apply a coating of primer and 2 moppings of asphalt. Begin dampproofing application at the low point of the surface being treated. Apply primer at an approximate rate of 0.41 L/m2 (0.09 gal/yd2) and allow to dry before the first coat of asphalt is applied. Apply asphalt at a temperature between 149 °C and 177 ° C (300 °F and 350 °F). Apply each mopping of asphalt at the rate of approximately 1.6 L/m2 (0.35 gal/yd2). The total thickness of the 2 coats shall be approximately 2 mm (0.08 in.). After the first mopping of asphalt has set sufficiently, mop on the second coating. Take special care to ensure that there are no skips in the coatings and that all surfaces are thoroughly covered.
646.03.02 Waterproofing. Make concrete surfaces smooth and free of depressions and projections which
might damage the waterproofing. The surface shall be dry and cleaned of dust and loose materials. Do not apply primer or asphalt in wet weather, nor when the surface temperature is either below 4 °C (40 °F) or below t hat recommended by the manufacturer. Do not apply waterproofing until prepared to follow its application with the placement of the backfill within a sufficiently short time so that the waterproofing will not be damaged as a result of exposure to weatherin g. Remove waterproofing which loses its bond with the concrete and replace with acceptable waterproofing. Apply a coating of primer and 2 layers of glass fabric within 3 moppings of asphalt. Apply primer at an approximate rate of 0.41 L/m 2 (0.09 gal/yd2) and allow to dry before the first coat of asphalt is applied. 646 DAMPPROOFING , WATERPROOFING , SEALING , AND MEMBRANES Apply asphalt at a temperature between 149 °C and 177 °C (300 °F and 350 °F). Apply each mopping of asphalt at a rate not less than 1.6 L/m2 (0.35 gal/yd2) on horizontal surfaces and not less than 2.0 L/m2 (0.44 gal/yd2) on vertical surfaces. Apply waterproofing across all expansion joints unless otherwise directed. Begin at the lowest point of the surface and mop on asphalt slightly wider than half the width of the fabric. Immediately roll a strip of fabric of half the width of the roll onto the hot asphalt and carefully press into place so as to eliminate all air bubbles and obtain close conformity with the surface. Lay fabric so that drainage is over, and not against or along the laps. Mop asphalt on this first strip and an adjacent section of the surface of a width equal to slightly more than half the width of the fabric being used. Then roll a full width of the fabric into this asphalt, completely covering the first strip, and press into place as before. Mop this second strip and an adjacent section of the concrete surface with hot asphalt and shingle on the third strip of fabric so as to lap the first strip by not less than 50 mm (2 in.). Continue this process of lapping each strip of fabr ic at least 50 mm (2 in.) over the strip placed before the last strip until the entire surface is covered with 2 layers of fabric. Lap the ends at least 300 mm (12 in.). Mop the entire surface with hot asphalt after all fabric is placed. Regulate the work so that at the close of the day’s work all fabric in place is mopped. Take special care at all laps to see that they are thoroughly sealed down.
646.03.0 3 Crack Sealant. Prior to application, the concrete surfaces shall be dry according to the
manufacturer’s recommendations. Prior to starting work, submit material safety data sheets for the selected material . Protect pedestrians, vehicles, private property , and the adjacent traveled way during application. Arrange to have a skilled technical representative from the manufacturer on- site to provide training and guidance on mixing proportions, equipment, storage, handling, application, protective clothing, and safety. Have the qualified representative present prior to placement and on site until released by the Engineer. During application, t he concrete surface temperature shall be between 10 °C and 38 °C (50 °F and 100 °F) or as required by the manufacturer. Methods proposed to heat or cool the concrete surfac e shall be subject to approval. Apply the sealant using methods and equipment recommended by the manufacturer. Apply sealant at an approximate rate of 0.41 L/m 2 (0.09 gal/yd2). The application rate may be adjusted within the manufacturer’s recommended range and as advised by the technical representative. Flood surfaces with sealant allowing penetration and filling of all cracks. Redistribute the applied sealant in cracks by squeegees or brooms. The quantity of prepared sealant shall be no more than what i s needed for application. A noticeable increase in viscosity prior to placement shall be cause for rejection. Cover the treated area with dry sand at a rate of 1.0 kg/m2 to 1.2 kg/m2 (1.8 lb/yd2 to 2.2 lb/yd2), according to the manufacturer’s recommendations or before the crack sealant has begun to cure. Provide sand such that 95% shall pass the 2.36 mm (No. 8) sieve, and 95% shall be retained on the 850 μm (No. 20) sieve. Spread sand by a mechanical spreader. T he moisture content of the sand shall not exceed 1/2 of the aggregate absorption. Before the sealant begins to cure, fill areas with standing liquid with sand and finish to a uniform surface. Do not permit traffic on the treated surface until the sand cov er adheres sufficiently to resist brushing by hand.
646.03.0 4 Surface Seal ant. Prior to application, the concrete surfaces shall be dry according to the
manufacturer’s recommendations. Before starting work, submit material safety data sheets for the selec ted material . Protect pedestrians, vehicles, private property , and the adjacent traveled way during application . Arrange to have a skilled technical representative from the manufacturer on- site to provide training and guidance on mixing proportions, equipment, storage, handling, application, protective clothing, and safety. Have the qualified representative present prior to placement and on site until released by the Engineer. The surface temperature of areas receiving treatment shall be between 10 °C and 38 °C ( 50 °F and 100 °F) or within the temperature range recommended by the manufacturer. Do not apply material during rain, blowing winds , or other conditions that prevent proper application. DAMPPROOFING , WATERPROOFING , SEALING , AND MEMBRANES 646 Apply the sealant using methods and equipment recommended by the manufacturer . Apply sealant at an approximate rate of 0.41 L/m2 (0.09 gal/yd2). The application rate may be adjusted within the manufacturer’s recommended range and as advised by the technical representative. If required by the manufacturer, after application of the sealant , wet the concrete surface to insure proper reaction. Use the sealant as supplied by the manufacturer and do not dilute or alter in any way. Do not allow traffic on the treated surface until the solution has completely penetrated, been wetted (if required), and is completely dry.
646.03.0 5 Sheet and Liquid M embranes. Prior to application, the concrete surfaces shall be dry according to
the manufacturer’s recommendations. Before placing membranes , have the supplier fur nish the following:
1.A technical representative to provide on- site training to contractor personnel on equipment and procedures for preparing concrete surfaces and placing the membrane. The technical representative shall be present for the initial application of the membrane and for subsequent applications as directed.
2.A letter from the technical representative denoting the specific contractor personnel that the representative has provided job specific training to and is deemed qualified to supervi se installation of the membrane.
3.Health and safety training for personnel w ho are to handle the materials.
4.Material safety data sheets. Apply the materials using methods and equipment recommended by the manufacturer. Apply a primer if recommended by the manufacturer. Allow primer to dry until tack free before applying the membrane. Re- prime areas not covered with membrane within 24 hours. Apply sheet membranes in a manner that a shingling effect is achieved in the dir ection that water will drain. Roll with hand rollers or other equipment to develop a firm and uniform bond with the primed concrete surface minimizing wrinkles and air bubbles. At open joints, deck drains , and other locations as directed, cut the membrane sheet to extend into the opening and bond in place. Provide protection and take measures to ensure the function of bridge expansion joints and deck drains are not adversely impacted by the membrane installation. Extend the membrane up faces of barriers and curbs as shown in the plans or as recommended by the manufacturer. Provide flashing, fitted coverings , or other approved materials around projecting conduits or other elements passing through the membrane. Do not permit public traffic or non- essential construction traffic on prepared or primed surfaces. Patch damaged areas and areas with inadequate overlap according to the manufacturer’s recommendations. Apply suitable membrane top coat materials according to the membrane manufacturer’s recommendations for subsequent placement of bituminous surfacing. Use paving equipment that will not damage the membrane during placement of bituminous surfacing.
646.03.0 6 Bridge Deck Preparation. Use power sweeping, air blasting, shot blasting, sand blasting, high
pressure water washing, or steam cleaning methods to clean and prepare concrete surfaces for sealant and membrane applications . Do not unduly damage the concrete surface, remove or alter the existing surface texture, or expose the coarse aggregate of the c oncrete by the cleaning process. Detergents not to exceed 2% by mass may be used to aid in the cleaning process. Protect pedestrians, vehicles, private property , and the adjacent traveled way during cleaning and preparation. Prepare concrete surfaces as prescribed herein and in accordance with the recommendations of the manufacturer of the sealant or membrane to be applied to the surface. Remove all traces of curing compound, laitance, dust, dirt, salt, oil, asphalt , traffic stripes, pavement markings, and other foreign materials. 646 DAMPPROOFING , WATERPROOFING , SEALING , AND MEMBRANES Before preparing the entire surface, clean and prepare a test area of 2.3 m2 (25 ft2) minimum using the proposed methods and equipment. The test area will be evaluat ed as to whether the methods and equipment can produce the req uired surface preparation. If the specified surface preparation cannot be achieved, provide new methods or equipment that can produce the specified surface preparation. Provide written approval from the technical representative that proper surface preparation has been completed prior to commencing installation of the sealant or membrane. Do not allow traffic on cleaned and prepared concrete surfaces. Prior to applying sealant s, power sweep the entire concrete surface and blow all loose material from the surface and visible cracks using high pressure air. METHOD OF MEASUREMENT
646.04.01 Measurement. Bridge deck preparation will be measured by the square meter (square yard) .
Dampproofing and waterproofing will be measured by the square meter (square yard) of area covered. Crack sealant and surface sealant will be measured by the liter (gallon) based on mixed material actually placed. Sheet membrane and liquid membrane will be measured by the square meter (square yard) of area covered. BASIS OF PAYMENT
646.05.01 Payment. The accepted quantities, measured as provided above, will be paid for at the contract
price per unit of measurement for the pay items listed below that are shown in the proposal. Payment will be full compensation for the work pr escribed in this Section. Payment will be made under: Pay Item Pay Unit Bridge Deck Preparation .............................................................................................................................. Square Meter (Square Yard) Dampproofing ................................ ................................ .............................................................................. Square Meter (Square Yard) Waterproofing ................................ ................................ .............................................................................. Square Meter (Square Yard) Crack Sealant ................................ ................................ ...................................................................................................... Liter (Gallon) Surface Sealant ................................ ................................................................................................................................... Liter (Gallon) Sheet Membrane ......................................................................................................................................... Square Meter (Square Yard) Liquid Membrane ......................................................................................................................................... Square Meter (Square Yard) SECTION 660 P NEUMATICALLY PLACED CONCRETE MORTAR DE SCRIPTION 660.
01.01 General. This work consists of constructing reinforced pneumatically placed concrete mortar
surfaces for soil nail retaining walls. P neumatically placed concrete mortar (shotcrete) consists of either dry mixed fine aggregate and Portland cement applied by a suitable mechanism, to which water is added immediately before its expulsion from the nozzle, or mortar premixed by mechanical methods and pneumatically applied through a no zzle onto the prepared surface. P erform shotcrete construction concurrently with soil nail wall construction as specified in Section 644. 660.
01.02 Qualifications. Use workers, including foremen, nozzlemen, and delivery equipment operators,
experienced to perform the work. Shotcrete nozzlemen shall have experience on at least 3 projects in the past 3 years in similar shotcrete application work and demonstrate ability to satisfactorily place the shotcrete. I nitial qualification of nozzlemen will be based either on previous ACI certification or satisfactory completion of qualification test panels. The requirement for nozzlemen to shoot qualification test panels will be waived for nozzlemen who can submit documented proof they have been certified in accordance with the ACI 506.3R Guide to Certification of Shotcrete Nozzlemen. The Certification shall have been done by an ACI recognized shotcrete testing lab and/or recognized shotcreting consultant and have covered the type of shotcrete to be used (plain wet-mix, plain dry -mix). All nozzlemen will be required to periodically shoot production test panels during the course of the work at the frequency specified herein. G ive notification not less than 2 days prior to the shooting of qualification test panels to be used to qualify nozzlemen without previous ACI certification. Use the same shotcrete mix and equipment to make qualification test panels as those to be used for the soil nail wall shotcrete facing. Initial qualification of the nozzlemen will be based on a visual inspection of the shotcrete density and void structure and on achieving the specified 3 day and 28 day compressive strength requirements determined from test specimens extracted from the qualification tes t panels. Conduct qualification test panels, core extraction, and compressive strength testing in accordance with ACI 506.2 and AASHTO T24/ASTM C42, unless otherwise specified herein. 660.
01.03 Submittals. Submit 5 copies of the following information for review and approval at least 15 days
prior to beginning shotcrete placement: 1.D ocumentation of the nozzlemen's qualifications. 2.P roposed methods of shotcrete placement and of controlling and maintaining facing alignment and s hotcrete thickness. 3.S hotcrete mix design in accordance with Subsection 501.02.05, except cores from test panels or production panels will be used instead of cylinders and they will be tested as specified herein. 4.Manuf acturer Certificates of Compliance for drainage geotextile, geocomposite drain strip, drain grate and accessories, and PVC drain piping. 5.F ormwork dimensions and details for casting the CIP facing over the shotcrete construction facing. Include details for formwork connections to the shotcrete facing and/or nails (if applicable), proposed concret e pl acement method and placement rates, and accompanying structural calculations verifying the structural adequacy of the formwork, connections, and shotcrete facing and/or nails to support the loading induced bythe fluid CIP concrete. When anchors embedded into the shotcrete facing will be used to support the 1- sided CIP face form, include calculations illustrating the anchor design load (calculated as the design concrete fluid pressure times the anchor tributary area). The structural calculations shall be prepared and sealed by a Registered Professional Engineer licensed in the State of Nevada. A pproval or rejection of submittals will be given within 10 days after receipt of a complete submission. Do not begin shotcrete construction or incorporate materials into the work until the submittal requirements are satisfied and found acceptable. Changes or deviations from the approved submittals shall be re- submit ted for approval. No adjustments in contract time will be allowed due to incomplete submittals.
Source: Nevada Standard Specifications for Road and Bridge Construction, 2014 Edition. Pages 501–504 of 610.