1、Standard Practice for Evaluation of Precast Concrete Drainage Products AASHTO Designation: R 73-161Release: Group 2 (June 2016) American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001 TS-4a R 73-1 AASHTO Standard Practice for
2、 Evaluation of Precast Concrete Drainage Products AASHTO Designation: R 73-161Release: Group 2 (June 2016) 1. SCOPE 1.1. This standard practice describes the evaluation of precast concrete pipe, box culverts, manholes, and drainage inlets. This standard also describes criteria for acceptable product
3、s, repairable products, and the rejection of defective products. All repairs shall conform to the criteria found in this document or to contract documents as applicable. 1.2. This standard practice is applicable to storm water management precast concrete products, manufactured by both the wet cast a
4、nd dry cast production methods, after curing and prior to installation. 1.3. This standard practice covers the inspection of finished products manufactured per M 86, M 170, M 199, M 206, M 207, M 242, M 259, and M 273; and ASTM C443, C858, C913, C985, C1417, C1433, C1504, and C1577. 1.4. Evaluation
5、guidelines are included for the following conditions: cracks, manufacturing defects, and damaged ends. 1.5. This standard practice is not intended for the evaluation of installed precast concrete pipe, box culverts, three-sided structures, manholes, drainage inlets, or other precast products. 2. REF
6、ERENCED DOCUMENTS 2.1. AASHTO Standards: M 86, Nonreinforced Concrete Sewer, Storm Drain, and Culvert Pipe M 170, Reinforced Concrete Culvert, Storm Drain, and Sewer Pipe M 199, Precast Reinforced Concrete Manhole Sections M 206, Reinforced Concrete Arch Culvert, Storm Drain, and Sewer Pipe M 207, R
7、einforced Concrete Elliptical Culvert, Storm Drain, and Sewer Pipe M 242, Reinforced Concrete D-Load Culvert, Storm Drain, and Sewer Pipe M 259, Precast Reinforced Concrete Box Sections for Culverts, Storm Drains, and Sewers M 273, Precast Reinforced Concrete Box Sections for Culverts, Storm Drains,
8、 and Sewers with Less Than 2 ft of Cover Subjected to Highway Loadings T 280, Concrete Pipe, Manhole Sections, or Tile 2016 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4a R 73-2 AASHTO 2.2. ASTM Standa
9、rds: C443, Standard Specification for Joints for Concrete Pipe and Manholes, Using Rubber Gaskets C858, Standard Specification for Underground Precast Concrete Utility Structures C913, Standard Specification for Precast Concrete Water and Wastewater Structures C985, Standard Specification for Non-re
10、inforced Concrete Specified Strength Culvert, Storm Drain, and Sewer Pipe C1417, Standard Specification for Manufacture of Reinforced Concrete Sewer, Storm Drain, and Culvert Pipe for Direct Design C1433, Standard Specification for Precast Reinforced Concrete Monolithic Box Sections for Culverts, St
11、orm Drains, and Sewers C1504, Standard Specification for Manufacture of Precast Reinforced Concrete Three-Sided Structures for Culverts and Storm Drains C1577, Standard Specification for Precast Reinforced Concrete Monolithic Box Sections for Culverts, Storm Drains, and Sewers Designed According to
12、AASHTO LRFD 3. TERMINOLOGY 3.1. 0.01-in. crackthe crack has reached 0.01 in. in width when the point of the measuring gauge shown in Figure 1 will, without forcing, penetrate 1/16in. at close intervals throughout the 12 in. in length as shown in Figure 2. Figure 1Measuring/Leaf Gauge; Gauge Made fro
13、m Machinist Leaf of 0.01 in. in Thickness, Ground to a Rounded Point of 1/16in. in width with a taper of 1/4in./in. (Courtesy of ACPA) Figure 20.01-in. Crack Measurement (Photo Courtesy of ACPA) 1/16in.(Gauge Dimension)1/2in.1/4in./in.1/16in.(Crack Measurement)0.01 in. 2016 by the American Associati
14、on of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4a R 73-3 AASHTO 3.2. bleedoutleakage of the paste (cement, water, air, and fine aggregate particles) through form gaps and seams of the form that results in small voids or openings
15、between coarse aggregate particles. 3.3. bug holesbug holes are small irregular cosmetic cavities typically resulting from entrapment of air bubbles or water on the surface of formed concrete during placement and consolidation. 3.4. chipphysical damage (breakage) of the corner or edges of the produc
16、t. 3.5. damagephysical harm which impairs the products normal performance. 3.6. dry cast/packerhead concretea low water-cementitious materials ratio concrete (zero slump) cast by a method in which the product is demolded immediately after consolidating. 3.7. honeycombfailure of mortar to completely
17、surround coarse aggregate in concrete, leaving empty spaces (voids) between the coarse aggregate particles. 3.8. riflinga series of tool marks resembling spiral grooves on the interior of a round structure. These grooves are caused by the manufacturing process and are not typically an indication of
18、insufficient reinforcement cover. 3.9. sealing surfacearea of the joint which the gasket is capable of sealing. 3.10. semi-dry cast concretegreater than zero slump concrete that is consolidated with or without vibration in which the product is demolded once the concrete stiffens to the point where i
19、t can stand on its own. 3.11. slab offa result of separation (delamination) of freshly placed concrete, prior to initial set, which typically occurs at a steel reinforcement plane. 3.12. spallThe chipping or splintering of a localized area of cured concrete (usually in a circular or oval shape) brea
20、king loose from the steel reinforcement plane. 3.13. wet cast concrete greater than zero slump concrete that is consolidated with or without vibration in which the product is demolded after reaching a specified stripping and handling strength. 4. ACCEPTABLE DEFECTS IN PRECAST CONCRETE PRODUCTS 4.1.
21、Minor defects, which do not affect the performance or design life of the product as described in Sections 4.2 through 4.8, will not be cause for rejection or repair. 4.2. Acceptable Cracks for Nonreinforced Pipe: 4.2.1. Fractures or cracks not passing through the wall or joints, or a single end crac
22、k less than 2 in. in length at either end of a pipe, unless these defects exist in more than 5 percent of the entire shipment or delivery, shall be acceptable. 4.3. Acceptable Cracks for Reinforced Pipe: 4.3.1. A single end crack that does not exceed the depth of the joint as, shown in Figure 3, sha
23、ll be acceptable. 2016 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4a R 73-4 AASHTO Figure 3Acceptable Single End Crack (Photo Courtesy of ACPA) 4.3.2. Any continuous crack having a surface width less
24、than 0.01 in. wide, provided it does not pass through the wall as shown in Figure 4, shall be acceptable. Figure 4Acceptable Surface/Curing Crack (Photo Courtesy of ACPA) 4.3.3. Any continuous crack having a surface width of 0.01 in. or greater and less than 12 in. long, provided it does not pass th
25、rough the wall, shall be acceptable. 4.4. Acceptable Cracks for Precast Concrete Products Other Than Pipe: 4.4.1. A single end crack that does not exceed the depth of the joint as shown in Figure 5 shall be acceptable. 4.4.2. Cracks not passing through the wall shall be acceptable. 2016 by the Ameri
26、can Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4a R 73-5 AASHTO Figure 5Acceptable Cracks; Single End Crack Does Not Exceed Depth of Joint 4.5. Acceptable Manufacturing Defects: 4.5.1. Minor defects that do not affec
27、t the strength, durability, or function shall be acceptable. Examples include, but are not limited to: bug holes as shown in Figure 6 or imperfections as shown in Figure 7 inherent in the manufacturing process, or rifling as shown in Figure 8 less than 1/4in. in height. Acceptable cosmetic dimension
28、s of bug holes may be determined by the owner. Bug holes more severe than a cosmetic defect shall be subject to criteria in Section 5.3.2.1 and Section 6.4.4. Figure 6Acceptable Bug Holes and Shallow Pitting (Photo Courtesy of ACPA) 2016 by the American Association of State Highway and Transportatio
29、n Officials.All rights reserved. Duplication is a violation of applicable law.TS-4a R 73-6 AASHTO Figure 7Acceptable Lines Caused by Form Jacket during Stripping (Photo Courtesy of ACPA) Figure 8Acceptable Rifling (Photo Courtesy of ACPA) 4.6. Acceptable Damage and Chips to Ends of Non-Reinforced Pi
30、pe: 4.6.1. A single fracture or spall in the joints not exceeding 3 in. around the circumference of the pipe, nor 2 in. in length into joint, unless these defects exist in more than 5 percent of the entire shipment or delivery, shall be acceptable. 4.7. Acceptable Damage and Chips to Ends: 4.7.1. Da
31、mage or chips to ends that do not affect the function of the joint as shown in Figure 9 shall be acceptable. This damage can include handling marks, chips, and spalls. 2016 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of ap
32、plicable law.TS-4a R 73-7 AASHTO Figure 9Acceptable Chip on Bell End (Photo Courtesy of ACPA) 4.8. Exposed Positioning Devices: 4.8.1. The exposure of the ends of longitudinals, stirrups, or spacers that have been used to position the cages during the placement of the concrete, as shown in Figures 1
33、0 and 11, shall be acceptable. Figure 10Acceptable Exposed Longitudinal Reinforcement (Photo Courtesy of ACPA) 2016 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4a R 73-8 AASHTO Figure 11Acceptable Expo
34、sed Cage Spacer (Photo Courtesy of ACPA) 5. REPAIRABLE DEFECTS IN PRECAST CONCRETE PRODUCTS 5.1. Defects which can affect the function or design life of the precast product that can be adequately repaired to meet specification requirements shall be acceptable for repair as described in Sections 5.2
35、to 5.4. Any repairs made must be performed such that the structural integrity is not compromised and does not change the dimensional requirements of the product. Repairs made using commercially approved materials must be performed in accordance with the manufacturers recommendations. 5.2. Repairable
36、 Cracks in Reinforced Products: 5.2.1. Cracks can be repaired in accordance with Sections 5.2.2 and 5.2.3. 5.2.2. For pipe, cracks 0.01 in. or wider and longer than 12 in. that are not passing through the wall can be repaired with an approved repair material as described in the contract or approved
37、by the owner. 5.2.3. For other products, cracks passing through the wall can be repaired with an approved repair material as described in the contract or approved by the owner. 5.3. Repairable Uncured Manufacturing Defects: 5.3.1. Repairs specific to uncured dry cast, packerhead, and semi-dry cast p
38、roduct for slab off areas extending to the reinforcing steel shall commence within 1 h of casting the product by trowel-applying batched concrete from the same mix design, or approved concrete mix into the slab off area. 5.3.2. Repairs of Surface Defects in Cured Products: 5.3.2.1. Honeycombing and
39、bleedout surface conditions less severe than stated in Section 6.4.4, as shown in Figures 12, 13, and 14, are repairable. The repair area of any single defect must be less than 4 percent of the total external surface area. The cumulative repair area must be less than 10 percent of the external surfa
40、ce area in a product. 2016 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4a R 73-9 AASHTO Figure 12Repairable Honeycombing (Photo Courtesy of ACPA) 5.3.2.2. Form bleedout less severe than stated in Secti
41、on 6.4.4, as shown in Figures 13 and 14, is repairable. Before After Figure 13Acceptable Repair of Form Bleed (Photos Courtesy of ACPA) Figure 14Repairable Form Bleed on a Box Culvert (Photo Courtesy of ACPA) 2016 by the American Association of State Highway and Transportation Officials.All rights r
42、eserved. Duplication is a violation of applicable law.TS-4a R 73-10 AASHTO 5.3.2.3. For repairs, use plant-mixed or commercial patching material and techniques approved by the contract documents or approved by the owner. Remove all laitance, loose materials, form oil, curing compound, and any delete
43、rious matter from the repair area down to solid concrete. 5.3.3. Repairs of Slab Offs and Spalls in Cured Products: 5.3.3.1. Repair of slab offs and spalls less severe than stated in Section 6.4.5 is permissible. Remove substandard concrete, beyond the reinforcement if the product contains reinforci
44、ng to anchor the repair, and eliminate all feathered edges prior to repair as shown in Figure 15. The repair area of any single defect must be less that 4 percent of the total internal surface area. The cumulative repair area must be less than 10 percent of the internal surface area in a product. Be
45、fore After Figure 15Acceptable Repair of Box Culvert Sl ab Off (Photos Courtesy of ACPA) 5.3.3.2. Spalled areas at lifting holes as shown in Figure 16 (where lifting holes are allowed) that extend to reinforcing steel are acceptable for repair, provided these repairs do not compromise the design or
46、integrity of the lifting hole. Minor spalls at the lifting holes can be repaired at the same time the lifting hole is plugged in the field after installation of the product. Figure 16Repairable Damage to Lifting Holes (Courtesy of ACPA) 5.3.3.3. For repairs, use a plant-mixed or commercial patching
47、material as described in the contract or approved by the owner. Remove loose concrete materials and laitance prior to repair. Note 1As an option, concrete from the original mix design or a cementitious repair material using the same cement, fine aggregate, and coarse aggregate (if required due to de
48、pth, size of DDSection D-D(Acceptable for Repair) 2016 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4a R 73-11 AASHTO repair or other criteria) which will meet the required concrete mix design strength
49、and which can be placed and finished to required dimensional tolerances may be utilized. 5.4. Repair of Damaged or Chipped Ends: 5.4.1. Repair of Damaged or Chipped Ends for Non-Gasketed Joints: 5.4.1.1. If the damage or chip is less than 1 in. in depth from the end of the pipe on the bell or spigot, then the total circumference of the structure can be repaired. 5.4.1.2. Damage or chips in round structures 1 in. and greater in depth from the end of the bell or spigot and not exceeding the depth of the jo
