00536.00 468 Section 00536 - Internal Shear Anchors
Description
00536.00Scope - This Work consists of constructing internal shear anchors in existing concrete
beams that includes drilling and preparing holes, inserting epoxy resin, inserting steel rods, and repairing, patching, and finishing the concrete surface.
00536.02Plans - Plans of t he existing Structure are available from the Engineer . Prints of these
plans are available upon request.
00536.03Submittals - Submit the following for approval at least 12 Calendar Days before beginning
internal shear anchor Work :
• The manufacturer's recommended Materials. • Describe the M aterials to be used including the properties of each Material and the Specifications to which the M aterials comply. Published manufacturer data is acceptable. • Proposed changes to the required installation procedure.
Materials
00536.10Epoxy Resin - Furnish crack injection epoxy products from the QPL
00536.11Threaded Shear Anchors - Furnish fully threaded shear anchor rods meeting the
requirements of ASTM A449 or ASTM A193 (Grade B7). Furnish one extra anchor r od from each separate lot for check testing.
00536.12Concrete Repair - Furnish PCC repair Material meeting the requirements of
00536.13Epoxy Resin Manufacturer's Recommendations - Submit the following manufacturer's
recommendations to the Engineer before beginning installation:
• Confirmation that the proposed products are suitable for the internal shear anchor application. • Confirmation that the proposed products can be installed according to 00536.41 and 00536.42 or, if not, the manufacturer's recommended changes to the installation procedures. • The estimated time it will take the epoxy resin to reach a minimum compressive strength of 3,000 psi at the anticipated installation temperatures.
Construction
00536.40General - Mark anchor locations on the bridge member for each entire span before drilling
anchor holes for that span. Obtain the Engineer's approval of each span, before drilling the holes.
Install the epoxy resin according to the manufacturer's recommendations and the following:
• Install epoxy resin and anchors when the ambient air temperature is above 50 ºF. • Complete installation of the internal shear anchors within 12 Calendar Days of dril ling the holes.
00536.41 469 00536.41 Internal Shear Anchors - Bottom :
installed from the bottom in the presence of the Engineer using the same Materials, Equipment , and installation methods that will be used for the final installation. Perform the de monstration according to the following:
• Construct a frame that can support and orient a PVC pipe at the angles and the lengths of the finished installed anchors. For variable angles and non-variable lengths perform the demonstration using the closest to vertical angle. For variable angles and variable lengths, perform either two demonstrations or one demonstration as follows: • For two demonstrations, perform the first demonstration using the longest anchor length at that anchor's corresponding angle. Perform the second demonstration using the closest to vertical angle at that anchor's corresponding length. • For one demonstration, perform the demonstration using the longest anchor length at the closest to vertical angle. • Use clear Schedule 40 PVC pipe that ha s an internal diameter that matches the internal diameter of the specified anchor hole within a tolerance of ± 1/4 inch. Cap the top of the PVC pipe. • Insert the anchor rod into the PVC pipe then inject the epoxy resin. Simulate the anchor rod placement c onditions including temperature, humidity, geometry, injection pressure, and the method that will be used to prevent the epoxy resin from escaping. Measure the quantity of resin injected. • After curing, cut the demonstration specimen into three separate sections, as directed. • If required, perform additional demonstrations until the Engineer is satisfied that the epoxy resin has been fully distributed throughout the PVC pipe.
Do not begin drilling holes in the Bridge until the Engineer has provided written approval of the demonstration.
shear anchors from below:
• Lay out and mark proposed anchor locations. • Locate existing reinforcement by using an electronic rebar mapping device or by removing a 6 inch maximum diameter plug of concrete, as required, to expose the existing bottom layer of longitudinal reinforcement at the locations shown. If locations are not shown, perform concrete removal at enough locations to determine the location of the existing bottom longitudinal reinforcement. • After locating the reinforcement, drill an 8 inch deep hole using a carbide bit rotary hammer. If existing reinforcement is encountered, stop drilling and adjust the hole location. Unless shown or approved, adjust the hole location up to 3 inches in any direction. If existing reinforcement is not encountered, drill the hole to the required depth using a diamond bit core drill. • Clean and scarify the hole with a high- pressure water sy stem that has a rotating tipped wand and can deliver water at a water pressure of approximately 17,000 psi. • Brush the hole with a nonmetallic brush. • Flush the hole with water and compressed air. 00536.42 470 • Tie a sponge or rag to a section of scrap rebar. Test the dr illed hole for concrete dust and debris by touching the tip and sides of the hole with the sponge or rag. Repeat water flush and compressed air procedure until no evidence of concrete dust and debris is observed on the sponge or rag. • Measure and record th e length and diameter of the drilled hole. • Let all water drip from the hole before proceeding. • Insert the anchor rod into the hole and inject the epoxy resin. Measure and record the volume of epoxy resin used. • Patch the beam bottom surface using a PCC repair material . • Submit the measured depth, diameter, and volume of epoxy resin of each hole and the total recorded volume of epoxy after installation is complete.
00536.42Internal Shear Anchors - Top - Unless otherwise approved, use the following procedure
to install internal shear anchors from above:
• Lay out and mark proposed anchor locations. • Locate existing reinforcement by using an electronic rebar mapping device or drill an 8 inch deep hole using a carbid e bit rotary hammer. If existing reinforcement is encountered, stop drilling and adjust the hole location. Unless shown of approved, adjust the hole location up to 3 inches in any direction. If existing reinforcement is not encountered, drill hole to the required depth using a diamond bit core drill. • Clean and scarify the hole with a high-pressure water system that has a rotating tipped wand and can deliver water at a water pressure of approximately 17,000 psi. • Vacuum the hole with a minimum 30 hp vacuum . Attach a PVC pipe or other type of extension to the end of the vacuum hose to reach the bottom of the hole. • Tie a sponge or rag to a section of scrap rebar. Test the drilled hole for standing water and debris by touch the bottom of hole with the sponge or rag. Repeat vacuuming until no evidence of water or debris is observed on the sponge or rag. • Plug the hole until epoxy resin is installed. • Before installing the anchor rod and epoxy resin, remove the plug and perform testing and cleaning described above. • Inject the epoxy resin into the hole to cover the top of the anchor rod. • Insert the anchor rod and twist it at least 360 degrees during the insertion process. • Remove excess liquid epoxy resin from the top of the hole. • Repair the deck with a PCC repair material . Remove all loose material according to the manufacturer's recommendations for patch preparation. Provide a patched surface finish that matches the appearance of adjacent deck sections. • Cure the epoxy resin to the manufacturer's recommended time to reach 3,000 psi compressive strength and cure the PCC repair material as recommended by the manufacturer before opening the section to traffic.
Measurement
00536.80Measurement - The quantities of Work performed under this Section will be measured
according to the following:
00536.90 471 Payment
00536.90Payment - 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.
No separate or additional payment will be made for anchor rods used for check testing, for adjusting and redrilling holes, repairing, patching, or surface finish Work .