580STRUCTURAL CONCRETE REPAIR

580.01 DESCRIPTION . This work shall consist of the removal and disposal of delaminated and unsound

concrete from an existing superstructure or substructure and its replacement with new Portland cement concrete or concrete repair material. The work under this section shall be performed in accordance with these provisions, the Plans, and Section 541.

580.02 MATERIALS . Materials shall meet the requirements of the following subsections:

Portland Cement ................................ ................................ ................................ ...... 701.02 Portland -Limestone Cement ................................ ................................ ..................... 701.0 5 Epoxy Bonding System, Type V ................................ ................................ .............. 719.0 1(b) Concrete Curing Materials ................................ ................................ ....................... 725.01 Water ................................ ................................ ................................ ....................... 745.01 Concrete Repair Material, Type I ................................ ................................ ............. 780.01(a) Concrete Repair Material, Type II ................................ ................................ ............. 780.01(b) Concrete Repair Material, Type III ................................ ................................ ............ 780.01(c) Concrete Repair Material, Type IV ................................ ................................ .......... 780.01(d) Coarse aggregate for concrete shall meet the requirements of Table 704.02 B. Concrete shall meet the requirements of Section 541 .

580.03 GENERAL REQUIREMENTS . The depth of superstructure repair shall be as defined in Table

580.03A and the depth of substructure repairs shall be as defined in Table 580.03B . For each identified repair area, concrete shall be removed until sound concrete is encountered and the minimum depth of the required repair classification is met. If sound concrete is not encountered within the removal limits for a given repair classification, concrete removal shall continue and the repair shall conform to the requirements of the subsequent r epair classification. If the Contractor removes sound concrete to a depth greater than the maximum allowed in the required classification, and exposes more than half of the bar diameter for reinforcing steel beyond the maximum removal limits , the concrete repair area shall be extended to the next classification of repair at no additional cost to the Agency. 5-345 TABLE 580.03A – SUPERSTRUCTURE REPAIR CLASSIFICATIONS Superstructure Repair Class Minimum Removal 1 Maximum Removal 1 Class I 1 inch Closest face of first mat of reinforcing Class II 3/4 inch beyond the furthest face of first mat of reinforcing Closest face of second mat of reinforcing Class III Full deck thickness N/A 1 As measured from the plane of the original concrete surface in the repair area. TABLE 580.03B – SUBSTRUCTURE REPAIR CLASSIFICATIONS Substructure Repair Class Reinforced Concrete Unreinforced Concrete Minimum Removal 1 Maximum Removal 1 Minimum Removal 1 Maximum Removal 1 Class I 1 inch Closest face of first mat of reinforcing 0 inches 3 inches Class II 3/4 inch beyond the furthest face of first mat of reinforcing 6 inches 2 3 inches 6 inches Class III 6 inches 2 N/A 2 6 inches N/A 1 As measured from the plane of the original concrete surface in the repair area. 2 If reinforcing steel is encountered within the specified removal limits and more than half of the bar diameter is exposed, additional concrete shall be removed to a minimum of 3/4 inch beyond the furthest face of the bar. The maximum removal limit for the specified class shall be extended to meet this requirement if necessary. Unless otherwise specified on the Plans, all superstructure repairs shall be performed with Class HPAA concrete, all substructure repairs shall be pe rformed with Class HPAA concrete or Class SCC concrete, and all overhead repairs shall be performed with Type I concrete repair material. When the use of concrete repair material is specified on the Plans, it shall be used in accordance with Table 580.03C . 5-346 TABLE 580.03C – CONCRETE REPAIR MATERIAL APPLICATIONS Type of Concrete Repair Material Position Formed or Unformed Type I Vertical or overhead Unformed Type II 1 Vertical or horizontal Formed Type III 1 Vertical or horizontal Formed Type IV 2 Overhead, vertical, or horizontal Formed or unformed 1 The layer thickness of the repair area shall be used to determine whether Type II concrete repair material or Type III concrete repair material will be used for formed vertical and horizonta l repairs. 2 Type IV concrete repair material shall only be used when specified on the Plans.

580.04 PROPORTIONING AND MIXING . All concrete repair materials shall be mixed with a

mechanical mixer at the project site in accordance with the manufacturer's recommendations on the project packaging, one bag (unit) at a time. The product shall not be extended with sand or gravel, except for Type III concrete repair material when mixed with approved aggregates in conformance with the manufacturer’ s recommendations. At no time shall the recommended water content be exceeded, nor shall any mixture be re -tempered by adding water or remixing once the material has reached initial set. Type III concrete repair material shall be mixed with approved materials in the proportions designated by the manufacturer or by the Structural Concrete Engineer.

580.05 SURFACE PREPARATION FOR REPAIRS AND MEMBRANES . Surfaces to be repaired shall

be remo ved to sound concrete as directed by the Engineer using approved hand tools, power -driven chipping hammers, or hydro -demolition. When existing reinforcing steel is specified to remain, concrete removal methods shall avoid damaging the reinforcing steel. If the methods of concrete removal cause any damage to reinforcing steel, the Contractor shall replace the damaged reinforcing steel at no additional cost to the Agency and lighter methods of concrete removal shall be used. The use of machine mounted hydraul ic hammers is prohibited. 5-347 When removing unsound portions of an existing structure in preparation for repair, the edges of all areas to be repaired shall be saw -cut in straight lines to a minimum depth of 1 inch. If methods of concrete removal damage squ are saw -cut edges, they shall be recut at no additional cost to the Agency. After complete removal of unsound concrete, the entire concrete surface to be patched, and all exposed steel which will have concrete placed against or around it, including metal plate expansion joints, scuppers, finger plate expansion joints, reinforcing steel, etc., shall be abrasive blast -cleaned a maximum of 24 hours prior to placing the new concrete. Exposed steel shall be abrasive blast -cleaned to a white metal finish. All re pair areas shall be flushed using high -pressure air or water to remove all loose particles, dust, and debris. Air used for cleaning shall be free of oil and other contaminants. After blast -cleaning, once the concrete is wet, whether from flushing or rain, the concrete shall be kept wet until the placing of concrete materials. If the concrete is allowed to dry out or the 24 -hour time limit has lapsed, the entire area shall be blast - cleaned and flushed again. Where concrete repair materials are specified, s urface preparation required by the manufacturer shall be performed in addition to the requirements of this subsection. Surface preparation for membranes shall include all necessary griding required to produce a smooth uniform surface for application of a waterproofing membrane. Hand -held grinders, or a wheel mounted grinder unit specifically designed for the purpose, shall be used. Ridges or areas of unevenness designated by the Engineer shall be ground so that no surface deviation greater than 1/16 inch r emains. Further surface preparations shall be performed as required by the manufacturer of waterproofing membrane system. Where the pay item Surface Preparation for Membrane is not included on the Plans, preparing surfaces of superstructure repairs for mem brane will be considered incidental to the applicable superstructure repair item.

580.06 FORMS . In addition to the requirements of Subsection 541.08 , the forms shall be constructed in

such a manner that the final concrete surface has the same architectural score marks and exterior face appearance as the original surface.

580.07 PLACING CONCRETE . In addition to the requirements of Subsection 541.07 and Subsection

541.09 , the following is applicable to concrete repair:

580.08 CURING CONCRETE . Concrete repairs shall b e cured in accordance with Subsection 541.15

and the requirements of this subsection. All concrete repairs shall be cured for 7 days regardless of the curing method chosen. Concrete patches shall be wet cured using one of the methods provided in Subsection 541.15(b) . The method described in Subsection 541.15(b)(6) may only be used for unformed vertical and overhead repairs performed with Type I concrete repair material. Membr ane-forming curing compounds shall be removed from the concrete surface prior to the application of silane per the manufacturer’s instructions. If the method used does not produce the desired results, alternate curing procedures may be required by the Engi neer. Evidence of improper cure could be a dry surface, a cracked or cracking surface, or a streaked or blotchy appearance of the surface. Concrete repair materials shall be cured in accordance with the manufacturer's recommendations on the product packagi ng or specification sheet. Where the manufacturer’s recommendations do not specify curing requirements, the concrete repairs shall be cured in accordance with this subsection.

580.09 METHOD OF MEASUREMENT . The quantity of Repair of Concrete Superstructure Surface,

Class I and Repair of Concrete Superstructure Surface, Class II to be measured for payment will be the number of square yards of concrete surfaces repaired. The quantity of Repair of Concrete Superstructure Surface, Class III to be measured for payment will be the number of cubic yards of concrete or concrete repair material, as applicable, placed. The quantity of Repair of Concrete Substructure Surface, Class I and Repair of Concrete Substructure Surface, Class II to be measured fo r payment will be the number of square yards of substructure surfaces repaired. The quantity of Repair of Concrete Substructure Surface, Class III to be measured for payment will be the number of cubic yards of concrete or concrete repair material, as appl icable, placed. The quantity of Surface Preparation for Membrane to be measured for payment will be the number of square feet of surface prepared. Payment will be made for surface preparation of existing surfaces, with no deductions made for areas of new patches. 5-349 The quantity of Concrete Repair Material, Type I; Concrete Repair Material, Type II; and Concrete Repair Material, Type III to be measured for payment will be the number of cubic feet of material mixed for use, as approved by the Engineer. The volume will be computed on the basis of the quantity identified as being contained in the product packaging. The quantity of Concrete Repair Material, Type IV to be measured for payment will be the number of cubic yards of material mixed for use, as approv ed by the Engineer. The volume will be computed on the basis of the quantity identified as being contained in the product packaging.

580.10 BASIS OF PAYMENT . The accepted quantity of Repair of Concrete Superstructure Surface,

Class I; Repair of Concrete S uperstructure Surface, Class II; Repair of Concrete Substructure Surface, Class I; and Repair of Concrete Substructure Surface, Class II will be paid for at the Contract unit price per square yard. The accepted quantity of Repair of Concrete Superstructur e Surface, Class III and Repair of Concrete Substructure Surface, Class III will be paid for at the Contract unit price per cubic yard. Payment will be full compensation for performing the work, including surface preparation as specified, removal and repl acement of concrete, satisfactory completion of curing, and for furnishing all forms, materials (including joint filler), labor, tools, admixtures, equipment, and incidentals necessary to complete the work. The cost of heating or cooling materials and prot ecting the concrete against cold weather and any additional cost for cement shall be included in the Contract unit price for the applicable concrete repair item in the Contract. Duplicate payment will not be made for preparation of concrete surfaces in any area. For example, if an area is originally prepared as Class I and the Engineer orders a change to the Class II depth, the area will be paid as Class II. The accepted quantity of Surface Preparation for Membrane will be paid for at the Contract unit pric e per square foot. Payment will be full compensation for furnishing all labor, tools, equipment, and incidentals necessary to complete the work. The accepted quantity of Concrete Repair Material, Type I; Concrete Repair Material, Type II; and Concrete Repa ir Material, Type III will be paid for at the Contract unit price bid per cubic foot. Payment will be full compensation for furnishing, transporting, storing, handling, and placing the materials specified and for furnishing all labor, tools, equipment, and incidentals necessary to complete the work. The accepted quantity of Concrete Repair Material, Type IV will be paid for at the Contract unit price per cubic yard. Payment will be full compensation for furnishing, transporting, storing, handling, and placi ng the materials specified and for furnishing all labor, tools, equipment, and incidentals necessary to complete the work. 5-350 Payment will be made under: Pay Item Pay Unit 580.1001 Repair of Concrete Superstructure Surface, Class I ................................ ..Square Yard 580.1002 Repair of Concrete Superstructure Surface, Class II ................................ Square Yard 580.1003 Repair of Concrete Superstructure Surface, Class III ............................... Cubic Yard 580.1101 Repair of Concrete Substructure Surface, Class I ................................ .....Square Yard 580.1102 Repair of Concrete Substruc ture Surface, Class II ................................ ...Square Yard 580.1103 Repair of Concrete Substructure Surface, Class III ................................ ..Cubic Yard 580.1201 Concrete Repair Material, Type I ................................ ............................ Cubic Foot 580.1202 Concrete Repair Material, Type II ................................ ........................... Cubic Foot 580.1203 Concrete Repair Material, Type III ................................ ........................... Cubic Foot 580.1204 Concrete Repair Material, Type IV ................................ ......................... Cubic Yard 580.1600 Surface Preparation for Membrane ................................ ........................... Square Foot 5-351 SECTION 590 – BUILDINGS

590.01 DESCRIPTION . This work shall consist of constructing buildings at the locations shown in the

Plans and as directed by the Engineer.

590.02 MATERIALS . Materials shall meet the requirements of the following subsections:

Mortar, Type IV ................................ ................................ ................................ ......... 707.0 1(e) Joint Sealant, Elastomeric ................................ ................................ .......................... 707.1 6 Joint Sealant, Latex ................................ ................................ ................................ ....707.1 7 Structural Lumber and Timber ................................ ................................ ................... 709.01 Structural Steel ................................ ................................ ................................ ........... 714.02 Carbon Steel Bolts, Nuts, and Washers ................................ ................................ .....714.04 Anchor Bolts for Bearing Devices ................................ ................................ ............. 714.08 Roofing Systems ................................ ................................ ................................ ........ 715.0 4 Epoxy Bonding System s ................................ ................................ ............................ 719.01 Paint shall be a durable, latex -based, exterior paint. The paint shall be a green color that matches the green roof color as closely as possible. The color shall be approved by the Engineer. The moisture content requirements of Subsection 709.01(b) will not apply to timbers where the actual (dressed) width and thickness of the timber are both greater than or equal to 5 inches. Oil sealers shall maintain stability under freeze/thaw conditions, provide deep penetration, shall be capable of being reapp lied without sanding or stripping, contain no toxic solvents or chemicals, and provide UV, mildew, and rot protection.