00538.00 472 Section 00538 - Crack Injecting Existing Bridges
Description
00538.00Scope - This Work consists of cleaning, sealing, and injecting cracks that are 1/64 inch
and greater in width in existing concrete bridge members as shown.
00538.01Submittals - Submit the following for approval at least 6 Calendar Days before beginning
Work :
• Personnel qualifications. • The manufacturer's recommended Materials. • Describe the M aterials to be used including the properties of each Material and the Spec ifications to which the M aterials comply. Published manufacturer data is acceptable. • An injection procedure for performing the Work .
Materials
00538.10Epoxy Resin - Furnish crack injection epoxy from the QPL
00538.11Surface Seal - Furnish epoxy paste surface seal that is compatible with the epoxy resin
00538.12Portland Cement Concrete Patching Material - Furnish PCC patching Material meeting
the requirements of Section 02015.
00538.13Epoxy Resin Manufacturer's Recommendations - Submit the following manufacturer's
recommendations to the Engineer before beginning Work :
• The range of crack width over which the product is effective. • The horizontal, vertical, and overhead orientation of cracked surfaces that the epoxy resin can be used. • The cleaning requirements for epoxy resin. • The estimated time it will take for the epoxy resin to reach a minimum compressive strength of 1,500 psi at the anticipated installation temperatures.
Labor
00538.30Personnel Qualificatio ns - Provide personnel skilled in the application of epoxy crack
injection. Experience shall be relevant to anticipated conditions, Materials, and construction techniques for epoxy crack injection. The on- site epoxy crack injection supervisor shall have successfully completed at least three projects within the past 5 years. Submit personnel experience documentation and, for the on-site supervisor a brief description of each of the three projects the on- site supervisor supervised. For each project, incl ude the project name, location, year of construction, owner's contact name, and current phone number.
The Engineer will respond within 7 Calendar Days after receipt of the submittal. If, after checking references, the Engineer determines that the proposed personnel are not qualified, they will not be allowed to w ork on the Project. Do not begin crack injection Work until the Engineer has approved, in writing, the proposed personnel.
The Engineer may suspend the epoxy crack injection Work if the Contract or substitutes unapproved personnel during construction. Submit requests to substitute the on-site supervisor or other 00538.50 473 personnel. The Engineer will respond to the substitute request 7 Calendar Days after receiving each request. Additional costs resulting from the suspension of Work due to the changing of personnel is the Contractor's responsibility, and no adjustment in C ontract Time resulting from the suspension of Work will be made.
Construction
00538.40General - Remove dirt, dust, grease, oil, efflorescence, and other foreign material from
surfaces adjacent to the cracks to be injected. Clean the crack with compressed air. Test the compressed air for oil and water according to ASTM D4285. Perform other cleaning requirements that are recommended by the epoxy resin manufacturer. Provide entry ports along the crack at intervals of not more than the thickness of the concrete at that location. Apply epoxy paste surface seal along the entire exposed face of the crack between entry ports. Allow the epoxy paste surface seal to cure before beginning epoxy crack injection Work .
Perform crack injection Work when the ambient girder temperature is above 40 °F or the manufacturer's recommended temperature, whichever is higher.
Begin injection Work at the lowest entry port. Continue injection Work until the crack is filled and epoxy resin appears at the next entry port. If port to port travel of epoxy resin is not apparent, stop Work and notify the Engineer. Do not restart Work until allowed by the Engineer.
After the injected epoxy resi n has cured, remove the epoxy paste surface seal and all epoxy resin runs and spills by grinding or by abrasive blasting.
00538.42Acceptance - Crack injection Work will be accepted visually by determining that the epoxy
resin has set and cured and that all cracks are sealed. If visual inspection reveals suspected failures, the Engineer will require cores samples. When required, provide 2 inch minimum diameter by 6 inch minimum depth core samples. The Engineer will determine the number of core samples and the locations to take the core samples. Take core samples at least 24 hours after the crack injection Work . When the crack injection Work is performed on only one side of the girder, take the core sample from the opposite side of the girder. When obtaining core samples do not cut or damage existing steel reinforcement. Fill core holes with a PCC repair material . If core samples show fully hardened epoxy resin and at least 90 percent of the crack is filled, the crack injection Work for that crack w ill be accepted. If core samples show inadequately hardened or inadequately filled cracks, stop all crack injection Work . Submit a revised crack injection procedure to the Engineer. Do not resume crack injection Work until the revised crack injection pr ocedure has been approved by the Engineer.
After approval of the revised crack injection procedure, re-inject all failed cracks to fill at least 75 percent of the crack volume.
Temporary
00538.50Traffic Control - In addition to the requirements of Se ction 00221 , provide traffic control
beginning with the application of epoxy paste surface seal and continue for 6 hours after completion of the crack injection Work or until the injected epoxy resin has reached a compressive strength of at least 1,500 psi whichever is less.
Unless otherwise shown, stage traffic so that the edge of the nearest travel lane is no closer than the center of the adjacent girder.
00538.80 474 Measurement
00538.80Measurement - The quantities of epoxy injected cracks will be measured on t he length
basis. The length will be determined by measuring the straight line distance between the beginning point and ending point of each filled crack.
Payment
00538.90Payment - The accepted quantities of epoxy injected cracks will be paid for at the Contract
unit price, per foot, for the item "Inject and Seal Cracks".
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 s eparate or additional payment will be made for providing core samples, patching core holes, or re-injecting cracks.