00504.00 414 Section 00504 - Concrete Deck Surface Preparation
Description
.00 Scope - This Work consists of preparing and patching concrete decks prior to surface treatment, membrane installation, or concrete overlay.
00504.01Definitions :
Bonded Membrane - A polymer or spray -on waterproofing membrane system that is fully or partially bonded to the concrete deck.
Class 1 Preparation - Deck surface preparation f or a membrane or overlay system on an existing bridge deck, where the existing concrete is sound, and minimal concrete removal is required to reach sound concrete.
Class 2 Preparation - Deck surface preparation in areas that are determined by the Engineer to have Unsound Concrete that requires concrete removal beyond the limits of Class 1 Preparation.
Class 3 Preparation - Deck surface preparation in areas where concrete removal extends through the full thickness of the deck.
Fabric Membrane - A rolled or sheet waterproofing membrane system that is installed below or between layers of asphalt Pavement.
Unsound Concrete - Delaminated or otherwise deteriorated concrete identified by a deck delamination survey or during surface preparation operations.
00504.02Submittals - Submit the type of Equipment that will be used for deck preparation to the
Engineer for approval at least 21 Calendar Days before the pre-placement conference.
Materials
00504.10Portland Cement Concrete Repair Material - Furnish PCC repair Material meeting the
requirements of Section 02015.
Equipment
00504.20General - Provide Equipment to perform concrete deck surface preparation. Remove all
Equipment that leaks oil or other contaminants from the work area until they are repaired.
00504.21Surface Preparation Equipment :
surface texture.
hydroblasting or shot blasting scarifying Equipment capable of uniformly removing the existing surface to depths required.
made up of diamond cutting blades.
on a rotary drum. Provide Equipment with tooth spacing of not more than 1/4 inch, capable of 00504.40 415 leaving a smooth, uniform pattern of striations. Limit machines to a gross operational weight of no more than 35 Tons and a forward speed to 2.5 feet per minute. Operate at a drum speed of at least 120 RPM.
or multiple blast wheels that cover a width of at least 2.5 feet per Pass, and conform to EPA air pollution requirements by containing dust and steel abrasive media. If the Equipment is not equipped for simultaneous bi -directional blasting, make separate passes in opposite directions to ensure equal cleaning on all sides of the exposed aggregate.
and volume acceptable to the Engineer without leaving a striated surface. Demonstrate the removal rate and accuracy of the Equipment to the Engineer before beginning Work. Hydroblasting may only be used during structural concrete overlay (SCO) installations.
Concrete meeting the following requirements:
Class 2 Preparation Equipment - For Class 2 deck preparation, use chipping hammers equal to or less than a nominal 15 pound class. Class 3 Preparation Equipment - For Class 3 deck preparation, use jackhammers equal to or less than a nominal 30 pound class.
to achieve the required depth.
used for blow -down of prepared surfaces is free of oil.
Construction
00504.40Ge neral Surface Preparation - Furnish surface preparation Equipment according
to 00504.21. Remove surface concrete by approved hand methods that cannot be reached by power - driven Equipment. Repair all damage to abutting concrete surfaces or other surfaces that are damaged by Contractor's operations at no additional cost to the Agency.
surface. Do not allow scarifying, chipping, sawing, sandblasting, shot blasting, water blasting or sweeping material to enter them.
surfaces and Fabric Membranes according to Section 00503.
by grinding, micro -milling, or other approved method. Do not exceed 1/4 inch of deck surface removal. If rutting is present in the existing concrete deck which has resulted in additional thickness of Bonded Membrane material, remove all existing Bonded Membrane material with Equipment that can sufficiently remove the material without exceeding 1/4 inch of PCC deck surface removal.
00504.41 416 (d) Multi -Layer Polymer Concrete Overlay (MPCO) Removal - Remove all existing MPCO material from the deck surface by grinding, micro- milling, or other approved method. Do not exceed 1/4 inch of PCC deck surface removal.
If rutting is present in the existing concrete deck which has resulted in additional thickness of MPCO material, remove all existing MPCO material with Equipment that can sufficiently remove the material without exceeding 1/4 inch of PCC deck surface removal.
deck surface by grinding, micro-milling, or other approved method. Do not exceed 1/4 inch of PCC deck surface removal.
If ruttin g is present in the existing concrete deck which has resulted in additional thickness of PPC material, remove all existing PPC material with Equipment that can sufficiently remove the material without exceeding 1/4 inch of PCC deck surface removal.
surface. Use Equipment that can sufficiently remove the overlay without exceeding 1/2 inch of parent deck removal. When hydroblasting Equipment is used to remove structural overlays, demonstrate that removal process and selected pressure will not exceed 1/2 inch of parent deck removal. If hydroblasting methods are unable to remove the structural overlay without damaging the parent deck, use scarifying equipment ac cording to 00504.21(b) to remove the structural overlay.
Removal of structural overlay below the top of the top mat of reinforcement is considered Class 2 Preparation.
hammering, or other approved method. Do not exceed 1/4 inch of deck surface removal.
00504.41Surface Preparation - Perform surface preparation far enough in advance of resurfacing
that all further deck preparation can be satisfactorily completed. Prepare the Bridge deck according to the following:
using chain drag or other approved methods that locates Unsound Concrete to determine limits of Class 2 Preparation. Class 2 Preparation limits to be verified by the Engineer.
Roughen the existing concrete surface to an exposed aggregate surface texture depth profile of at least 1/16 inch for PPC, MPCO, and membrane applications and 1/8 inch for SCO overlays. Deter mined profile according to ASTM E965 (standard volumetric test). Perform four tests per 500 square yards of concrete surface prepared, with a minimum of four tests per Day. Protect visible reinforcing steel and reinforcing steel where the Plans show it to be within 1/2 inch of the surface. Hydroblasting may only be used when preparing for SCO overlays.
Remove all Unsound Concrete from the lower limit of Class 1 Preparation down to sound concrete. 00504.42 417 Remove a minimum of 3/4 inch of concrete around and below reinforcing steel that is not at least 50 percent embedded in the existing concrete surface. If concrete removal extends to the bottom reinforcing mat, notify Engineer to determine further Class 2 Preparation or Class 3 Preparation limits. Sandblast reinforcing steel coated or pitted with rust to a bright finish.
Engineer and performed according to 00140.30.
Perform Class 3 Preparation as follows:
Remove the full thickness of deck remaining below the lower limit of Class 2 Preparation. Sandblast reinforcing bars pitted with rust to remove all rust.
repair the deck according to the following:
is compatible with the specified membrane or overlay. Cure the repair material according to the manufacturer's recommendations. Place the repair material at least 5 Calendar Days before placing the membrane or overlay or as recommended by the membrane or overlay manufacturer.
Fill repair areas with SCO during the overlay placement.
00504.42Final Surface Preparation -
the membrane or overlay, including vertical contact areas as follows:
Clean the entire surface by shot -blasting within 24 hours of placing the membrane or overlay. Sweep the area magnetically to remove metal residue. Blow clean the surfaces with compressed ai r. Immediately after surface preparation is complete cover the prepared deck with clear plastic, overlapping it to prevent contaminants from construction vehicles or other sources from contacting the deck. Maintain the covering until PPC, MPCO, or membrane installation. If the prepared surface becomes contaminated by spills, rain, or other contaminant before placing the membrane or overlay, prepare the surface again according to this Subsection.
profile of at least 1/8”, determined according to ASTM E965 (standard volumetric test). Perform four tests per 500 square yards of concrete surface prepared, with a minimum of four tests per D ay.
Clean the entires urface by shot -blasting. Shot -blasting is not required on final surfaces that were prepared by hydroblasting, chipping, or jack hammering. If shot-blasting was performed, sweep the area magnetically to remove metal residue. Clean with a power washer and sa turate the surface with water for a minimum of 8 hours before resurfacing. Remove standing water with compressed air or wet -dry vacuum ahead of concrete placement. 00504.80 418 Repeat cleaning and water saturation on areas that are allowed to dry or become contaminated before resurfacing. Immediately after surface preparation is complete cover the prepared deck with clear plastic, overlapping it to prevent contaminants from construction vehicles or other sources from contacting the deck. Maintain the covering until overlay installation.
Measurement
00504.80Measurement - The quantities of Work performed under this Section will be measured on
the area basis with the following exceptions:
Class 1 Preparation will not be measured. Removal of existing asphalt wearings urfaces and Fabric Membranes will be measured according to 00503.80.
Payment
00504.90Payment - The accepted quantities of Work performed under this Section will be paid for
at the Contract unit price, per unit of measurement, for the following items:
Pay Item Unit of Measurement
Payment will be payment in full for furnishing and placing all Materials, and for furnishing all Equipment, labor, and Incidentals necessary to complete the Work as specified. Payment for item (a) includes deck repair within the limits of Class 2 areas , according to 00504.41(e)(1) .
Payment of item (b) includes deck repair within the limits of Class 2 areas according to 00504.41(e)(2).
Payment of item (c), (d), and (e) includes material removal from within wheel ruts.
No separate or additional payment will be made for Class 1 Preparation Work or final surface preparation. Payment will be included in payment made for the appropriate items under which this Work is required. No separate or additional payment will be made for sealant removal.
Class 3 Preparation and deck repair within the limits of Class 3 areas, will be paid for according to 00195.20.
Removal of existing asphalt wearing surfaces and Fabric Membranes will be paid for according to 00503.90.