683 Curing Compound ....................................................... 912.01 Epoxy-Resin-Base System .......................................... 909.11 20 Fine Aggregate ............................................................ 904.02 Hydrated Lime ............................................................. 913.04 Masonry Cement ......................................................... 901.01(c) Packaged Patc hing Products ........................................ 901.08 Portland Cement, Type I .............................................. 901.01(b) Reinforcing Bars .......................................................... 910.01 Mortar shall consist of 1 part cement to 2 parts No. 23 fine aggregate, by volume. Packaged patching products containing magnesium phosphate or calcium 30 aluminate cement shall not be used. The Contractor shall provide product-specific documentation for proportioning, mixing, placement, curing, clean up and disposal of excess patching materials. CONSTRUCTION REQUIREMENTS
710.03 Patching Concrete Structures
a.Concrete Removal 40 Areas of unsound concrete to be remo ved will be marked by the Engineer. A saw cut shall be made perpendicular to the existing concrete surface a minimum of 1 in. outside marked areas. The cut shall be a minimum 1 in. deep or to the top of the reinforcement, whichever is less. Removal of unsound concrete shall not exceed 6 in. in depth and shall be performed by means of handchipping. Handchipping tools may be hand or mechanically driven. Jackhamm ers shall not be heavier than nominal 45 lb class and chipping hammers shall not be heavier than nominal 15 lb class. Only chipping 50 hammers shall be used when removing concrete within 1 in. of the reinforcement. Mechanically driven tools shall be operated at a maximum angle of 45° to concrete surfaces. Where the bond between the existing concrete and the reinforcement has been destroyed, concrete adjacent to the rein forcement shall be removed to a minimum clearance of 1 in. around the entire periphery of the exposed reinforcement. Exposed reinforcement shall not be damaged due to the removal operations. Reinforcement damaged by the Contractor shall be replaced. 60 Regardless of the method used, removal operations shall cease if sound concrete is being removed beyond the limits approved by the Engineer. Removal methods shall be adjusted to prevent unnecessary removal of sound concrete prior to resuming removal operations. 710.03
b.Replacement of Reinforcement Existing reinforcement that has lost 50% or more of its original cross-sectional area shall be removed and replaced with ne w reinforcement of th e diameter of the original reinforcement. Repl acement reinforcement shall be lapped a minimum of 3 in. along the existing reinforcement. 70
c.Patching After concrete removal operations are comp leted and just prior to placing patches, all patch areas shall be sandblasted to expo se aggregates in concrete surfaces and to remove rust, residual concrete, and la itance layers from the surface of the reinforcement. All surfaces shall be free of du st, chips, water, and foreign material to produce a firm, solid surface for adherence of patching concrete. Cleaning shall precede application of the patching material by not more than 24 h when packaged patching products are used. Air lines for sandblasting and air cleaning shall be equipped with oil and water traps. 80 Cavities of 1/2 in. depth or greater shall be filled with concrete or a packaged patching product. Cavities of less than 1/2 in. depth shall be filled with mortar or a packaged patching product. When using concrete or mortar patching materials, the surfaces of prepared cavities and all exposed reinforcement within the cavities shall be coated with an epoxy resin adhesive in accordance with 722.07(a)1. When packaged patching products are to be applied, all surface preparation and the use of bonding agents shall be as directed by the manufacturer. The surface shall be in saturated surface damp condition with no standing water on the surface unless otherwise directed by the manufacturer. 90 The packaged patching product shall be applied only to specific surface locations recommended by the manufacturer. Lifts of packaged patching products shall not be thicker than recommended by the manufacturer. Curing compound shall not be used between lifts. Packaged patching products may be extended with aggregate in accordance with the manufacturer’s recommendations. Concrete patches shall be finished to match the texture and finish of abutting existing concrete. 100
d.Curing For patched areas that require forms, forms may be removed after 24 h and surfaces cured in accordance with 702.22 or the forms may be left in place for 72 h and no additional curing will be required. Patched areas that do not require forms shall be cured in accordance with 702.22. Patches filled with packaged patching products shall be cured in accordance with the manufacturer’s recommendations.
710.04 Repointing Rubble Masonry 110
Joints in rubble masonry shall be cleaned of all loose mortar and foreign material. 710.04 685 All spaces around the rubble aggregate, after being cleaned, shall be filled with mortar and trowel finished. All loose rubble shall be settled into place before the mortar has set.
710.05 Repointing Dressed Stone and Brick Masonry Joints in masonry shall be cleaned of all loose mortar and foreign material for a
depth of at least twice the width of the joint. Joints shall be filled with mortar and trowel finished. 120
710.06 Method of Measurement
Patching concrete structures and repoi nting rubble, dressed stone and brick masonry in structures will be measured by the square foot of actual surface area of patching or repointing. Individual areas of less than 1 sq ft in area will be considered as 1 sq ft. Areas greater than 1 sq ft will be recorded as the actual measurement of the repaired area to the nearest 0.1 sq ft.
710.07 Basis of Payment
The accepted quantities of patching concrete structures will be paid for at the contract unit price per square foot, complete in place. Repointing rubble, dressed stone, 130 and brick masonry in structures will be paid for at the contract unit price per square foot of repointing masonry, complete in place. Payment will be made under: Pay Item Pay Unit Symbol Patching Concrete Structures..................................................... SFT Repointing Masonry in Structures ............................................. SFT Areas where patching concrete structures or repointing rubble, dressed stone, or brick masonry in structures exceeds an average of 4 in. in depth will be paid for at a price calculated by means of multiplying the contract unit price for the respective item by the following factors: (a) for portions whose average depth is greater than 4 in. but less than 6 in. ................................................ 1.25
b.for portions whose average depth is greater than or equal to 6 in. but less than 8 in. .............................. 1.50 150
c.for portions whose average depth is greater than or equal to 8 in. but less than 10 in. ............................ 1.75
d.for portions whose average depth is greater than or equal to 10 in. but less than 12 in. .......................... 2.00
e.for all portions whose average depth is greater than or equal 710.07 686 to 12 in., the work shall be done as extra work. Payment will be made in accordance with 104.03. 160 The cost of removing the existing concrete or masonry cement, furnishing, hauling, and placing all materials, preparin g the surface, and all necessary incidentals shall be included in the pay items in this section. The cost of replacing damaged reinforcement shall be included in the cost of patching concrete structures.
Source: Indiana Standard Specifications, 2024 Edition. Pages 692–696 of 1,248.