1、TS-4a M 273-1 AASHTO Standard Specification for Precast Reinforced Concrete Box Sections for Culverts, Storm Drains, and Sewers with Less Than 2 ft of Cover Subjected to Highway Loadings AASHTO Designation: M 273-111ASTM Designation: C 850-95a 1. SCOPE 1.1. This specification covers single-cell, pre
2、cast reinforced concrete box sections with less than 2 ft of cover subjected to highway loadings and intended to be used for the construction of culverts and for the conveyance of storm water, industrial wastes, and sewage. 1.2. A complete metric companion to M 273 has been developedM 273M; therefor
3、e, no metric equivalents are presented in this specification. Note 1This specification is primarily a manufacturing and purchasing specification. However, standard designs are included and the criteria used to develop these designs are given in Appendix X1. The successful performance of this product
4、 depends upon the proper selection of the box section, bedding, backfill, controlled manufacture in the plant, and care that the installation conforms to the construction specifications. The owner of the precast reinforced concrete box sections specified herein is cautioned that the loading conditio
5、ns and the field requirements must be correlated with the box sections specified and that inspection at the construction site must be provided. Note 2AASHTO M 259 is to be used for box sections subjected to highway loading with 2 ft or more earth cover, or subjected to dead load only. Note 3If load-
6、and-resistance factor design (LRFD) is required, then use ASTM C 1577. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standards: M 6, Fine Aggregate for Hydraulic Cement Concrete M 31M/M 31, Deformed and Plain Carbon-Steel Bars for Concrete Reinforcement M 32M/M 32, Steel Wire, Plain, for Concrete Reinforcemen
7、t M 55M/M 55, Steel Welded Wire Reinforcement, Plain, for Concrete M 80, Coarse Aggregate for Hydraulic Cement Concrete M 85, Portland Cement M 221M/M 221, Steel Welded Wire Reinforcement, Deformed, for Concrete M 225M/M 225, Steel Wire, Deformed, for Concrete Reinforcement M 240M/M 240, Blended Hyd
8、raulic Cement M 259, Precast Reinforced Concrete Box Sections for Culverts, Storm Drains, and Sewers 2013 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4a M 273-2 AASHTO M 262, Concrete Pipe and Related
9、Products M 295, Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in Concrete T 22, Compressive Strength of Cylindrical Concrete Specimens T 23, Making and Curing Concrete Test Specimens in the Field T 280, Concrete Pipe, Manhole Sections, or Tile Standard Specifications for Highway Bridges
10、2.2. ASTM Standards: C 1116/C 1116M, Standard Specification for Fiber-Reinforced Concrete C 1577, Standard Specification for Precast Reinforced Concrete Monolithic Box Sections for Culverts, Storm Drains, and Sewers Designed According to AASHTO LRFD 3. TERMINOLOGY 3.1. DefinitionsFor definitions of
11、terms relating to concrete pipe, see M 262. 4. TYPES 4.1. Precast reinforced concrete box sections manufactured in accordance with this specification shall be of the types identified in Tables 1 and 2, and shall be designated by type, span, and rise. 5. BASIS OF ACCEPTANCE 5.1. Acceptability of the
12、box sections produced in accordance with Section 7 shall be determined by the results of the concrete compressive strength tests described in Section 10, by the material requirements described in Section 6, and by inspection of the finished box sections. 5.2. Box sections shall be considered ready f
13、or acceptance when they conform to the requirements of this specification. 6. MATERIALS 6.1. Reinforced ConcreteThe reinforced concrete shall consist of cementitious materials, mineral aggregates, and water, in which steel has been embedded in such a manner that the steel and concrete act together.
14、6.2. Cementitious Materials: 6.2.1. CementCement shall conform to the requirements for portland cement of M 85 or shall be portland blast-furnace slag cement or portland-pozzolan cement conforming to the requirements of M 240M/M 240, except that the pozzolan constituent in the Type IP portland-pozzo
15、lan cement shall be fly ash and shall not exceed 25 percent by weight. 2013 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4a M 273-3 AASHTO Table 1Design Requirements for Precast Reinforced Concrete Box
16、Sections with Less Than 2 ft of Cover Subjected to HS20 Loadinga Box Section S R, ftbThickness, in. Circumferential Reinforcement AreascDistribution Reinforcement AreasdTop Slab Bottom Slab Wall As1As2As3As4As7As8As5As63 2 7 6 4 0.17 0.34 0.20 0.13e0.17e0.14e0.17e0.17e3 3 7 6 4 0.13e0.36 0.22 0.13e0
17、.17e0.14e0.18 0.17e4 2 71/26 5 0.21 0.37 0.20 0.13e0.18e0.14e0.18e0.18e4 3 71/26 5 0.18 0.41 0.23 0.13e0.18e0.14e0.20 0.18e4 4 71/26 5 0.16 0.43 0.24 0.13e0.18e0.14e0.21 0.18e5 3 8 7 6 0.22 0.41 0.22 0.14e0.19e0.17e0.19e0.19e5 4 8 7 6 0.19 0.44 0.24 0.14e0.19e0.17e0.21 0.19e5 5 8 7 6 0.16 0.46 0.26
18、0.14e0.19e0.17e0.22 0.19e6 3 8 7 7 0.30 0.42 0.21 0.17e0.19e0.17e0.19e0.19e6 4 8 7 7 0.59 0.46 0.24 0.17e0.19e0.17e0.20 0.19e6 5 8 7 7 0.23 0.48 0.26 0.17e0.19e0.17e0.21 0.19e6 6 8 7 7 0.20 0.51 0.29 0.17e0.19e0.17e0.22 0.19e7 4 8 8 8 0.32 0.45 0.24 0.19e0.19e0.19e0.19e0.19e7 5 8 8 8 0.29 0.48 0.27
19、0.19e0.20 0.19e0.19e0.19e7 6 8 8 8 0.27 0.51 0.29 0.19e0.20 0.19e0.20 0.19e7 7 8 8 8 0.25 0.53 0.32 0.19e0.23 0.19e0.21 0.19e8 4 8 8 8 0.37 0.51 0.27 0.19e0.19e0.19e0.19e0.19e8 5 8 8 8 0.34 0.53 0.30 0.19e0.19e0.19e0.20 0.19e8 6 8 8 8 0.32 0.56 0.33 0.19e0.25 0.19e0.21 0.19e8 7 8 8 8 0.30 0.58 0.35
20、0.19e0.27 0.22 0.22 0.19e8 8 8 8 8 0.28 0.60 0.38 0.23 0.29 0.26 0.22 0.19e9 5 9 9 9 0.34 0.50 0.29 0.22e0.22e0.22e0.22e0.22e9 6 9 9 9 0.32 0.53 0.32 0.22e0.22e0.22e0.22e0.22e9 7 9 9 9 0.30 0.55 0.35 0.22e0.25 0.22e0.22e0.22e9 8 9 9 9 0.28 0.57 0.38 0.22e0.27 0.24 0.22e0.22e9 9 9 9 9 0.27 0.58 0.41
21、0.25 0.30 0.28 0.22e0.22e10 5 10 10 10 0.34 0.48 0.29 0.24e0.24e0.24e0.24e0.24e10 6 10 10 10 0.32 0.50 0.32 0.24e0.24e0.24e0.24e0.24e10 7 10 10 10 0.31 0.52 0.35 0.24e0.24e0.24e0.24e0.24e10 8 10 10 10 0.29 0.54 0.38 0.24e0.26 0.24e0.24e0.24e10 9 10 10 10 0.27 0.55 0.40 0.24e0.28 0.26 0.24e0.24e10 10
22、 10 10 10 0.27 0.57 0.43 0.27 0.32 0.31 0.24e0.24e11 4 11 11 11 0.38 0.44 0.26e0.26e0.26e0.26e0.26e0.26e11 6 11 11 11 0.33 0.48 0.32 0.26e0.26e0.26e0.26e0.26e11 8 11 11 11 0.29 0.51 0.38 0.26e0.26e0.26e0.26e0.26e11 10 11 11 11 0.28 0.54 0.43 0.26e0.29 0.29 0.26e0.26e11 11 11 11 11 0.28 0.56 0.46 0.3
23、0 0.34 0.34 0.26e0.26e12 4 12 12 12 0.40 0.42 0.29e0.29e0.29e0.29e0.29e0.29e12 6 12 12 12 0.35 0.46 0.32 0.29e0.29e0.29e0.29e0.29e12 8 12 12 12 0.31 0.49 0.38 0.29e0.29e0.29e0.29e0.29e12 10 12 12 12 0.29e0.53 0.43 0.29e0.29e0.29e0.29e0.29e12 12 12 12 12 0.29e0.57 0.50 0.33 0.36 0.37 0.29e0.29ea Desi
24、gn requirements are based on maximum effects resulting from cover conditions ranging from 0 to 2 ft and the material and soil properties and loading data shown in Appendix X1. For modified or special designs, see Section 7.2. bThe box section designation, for example 3 by 2, indicates interior horiz
25、ontal span, in feet, by interior vertical rise, in feet. cDesign reinforcement areas in square inches per linear foot of box section length at those locations as shown in Figure 1. dDesign reinforcement areas in square inches per linear foot of box section width at those locations as shown in Figure
26、 1. eMinimum reinforcement area is specified. Notes: 1. Reinforcement areas are based on the weight of a column of earth over the width of the box section plus live loads as defined in Appendix X1. 2. Concrete design strength, 5000 psi. 2013 by the American Association of State Highway and Transport
27、ation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4a M 273-4 AASHTO Table 2Design Requirements for Precast Reinforced Concrete Box Sections with Less Than 2 ft of Cover Subjected to Interstate Loadinga Box Section S R, ftbThickness, in. Circumferential Reinforcemen
28、t AreascDistribution Reinforcement AreasdTop Slab Bottom Slab Wall As1As2As3As4As7As8As5As63 2 7 6 4 0.17 0.34 0.20 0.13e0.17e0.14e0.17e0.17e3 3 7 6 4 0.13e0.36 0.22 0.13e0.17e0.14e0.18 0.17e4 2 71/26 5 0.21 0.38 0.20 0.13e0.18e0.14e0.19 0.18e4 3 71/26 5 0.19 0.41 0.23 0.13e0.18e0.14e0.21 0.18e4 4 7
29、1/26 5 0.18 0.43 0.25 0.13e0.18e0.14e0.22 0.18e5 3 8 7 6 0.26 0.41 0.28 0.14e0.19e0.17e0.19e0.19e5 4 8 7 6 0.23 0.44 0.31 0.14e0.19e0.17e0.21 0.19e5 5 8 7 6 0.21 0.46 0.34 0.14e0.19e0.17e0.22 0.19e6 3 8 7 7 0.33 0.42 0.28 0.17e0.19e0.17e0.19e0.19e6 4 8 7 7 0.29 0.46 0.32 0.17e0.19e0.17e0.20 0.19e6 5
30、 8 7 7 0.27 0.48 0.34 0.17e0.19e0.17e0.21 0.19e6 6 8 7 7 0.25 0.51 0.37 0.17e0.19e0.17e0.22 0.19e7 4 8 8 8 0.33 0.45 0.31 0.19e0.19e0.19e0.19e0.19e7 5 8 8 8 0.30 0.48 0.34 0.19e0.20 0.19e0.19e0.19e7 6 8 8 8 0.28 0.51 0.37 0.19e0.20 0.19e0.20 0.19e7 7 8 8 8 0.26 0.53 0.39 0.19e0.23 0.19e0.21 0.19e8 4
31、 8 8 8 0.43 0.51 0.34 0.19e0.19e0.19e0.19e0.19e8 5 8 8 8 0.39 0.53 0.38 0.19e0.19e0.19e0.20 0.19e8 6 8 8 8 0.36 0.56 0.41 0.19e0.25 0.19e0.21 0.19e8 7 8 8 8 0.34 0.58 0.45 0.19e0.27 0.22 0.22 0.19e8 8 8 8 8 0.31 0.60 0.48 0.23 0.29 0.26 0.22 0.19e9 5 9 9 9 0.42 0.50 0.37 0.22e0.22e0.22e0.22e0.22e9 6
32、 9 9 9 0.39 0.53 0.40 0.22e0.22e0.22e0.22e0.22e9 7 9 9 9 0.37 0.55 0.44 0.22e0.25 0.22e0.22e0.22e9 8 9 9 9 0.34 0.57 0.47 0.22e0.27e0.24 0.22e0.22e9 9 9 9 9 0.32 0.58 0.50 0.25 0.30 0.28 0.22e0.22e10 5 10 10 10 0.44 0.48 0.36 0.24e0.24e0.24e0.24e0.24e10 6 10 10 10 0.41 0.50 0.40 0.24e0.24e0.24e0.24e
33、0.24e10 7 10 10 10 0.39 0.52 0.43 0.24e0.24e0.24e0.24e0.24e10 8 10 10 10 0.36 0.54 0.46 0.24e0.26 0.24e0.24e0.24e10 9 10 10 10 0.34 0.55 0.50 0.24e0.28 0.26 0.24e0.24e10 10 10 10 10 0.33 0.57 0.53 0.27 0.32 0.31 0.24e0.24e11 4 11 11 11 0.49 0.44 0.32 0.26e0.26e0.26e0.26e0.26e11 6 11 11 11 0.43 0.48
34、0.40 0.26e0.26e0.26e0.26e0.26e11 8 11 11 11 0.38 0.51 0.46 0.26e0.26e0.26e0.26e0.26e11 10 11 11 11 0.35 0.54 0.53 0.26e0.29 0.29 0.26e0.26e11 11 11 11 11 0.34 0.57 0.56 0.30 0.34 0.34 0.26e0.26e12 4 12 12 12 0.50 0.42 0.32 0.29e0.29e0.29e0.29e0.29e12 6 12 12 12 0.44 0.46 0.39 0.29e0.29e0.29e0.29e0.2
35、9e12 8 12 12 12 0.40 0.50 0.46 0.29e0.29e0.29e0.29e0.29e12 10 12 12 12 0.36 0.56 0.53 0.29e0.29e0.29e0.29e0.29e12 12 12 12 12 0.35 0.61 0.60 0.33 0.36 0.37 0.29e0.29eaDesign requirements are based on maximum effects resulting from cover conditions ranging from 0 to 2 ft and the material and soil pro
36、perties and loading data shown in Appendix X1. For modified or special designs, see Section 7.2. bThe box section designation, for example 3 by 2, indicates interior horizontal span, in feet, by interior vertical rise, in feet. cDesign reinforcement areas in square inches per linear foot of box sect
37、ion length at those locations as shown in Figure 1. dDesign reinforcement areas in square inches per linear foot of box section width at those locations as shown in Figure 1. eMinimum reinforcement area is specified. Notes: 1. Reinforcement areas are based on the weight of a column of earth over the
38、 width of the box section plus live loads as defined in Appendix X1. 2. Concrete design strength 5000 psi. 2013 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4a M 273-5 AASHTO 6.2.2. Fly AshFly ash shall
39、 conform to the requirements of M 295, Class F or Class C. 6.2.3. Allowable Combinations of Cementitious MaterialsThe combination of cementitious materials used in concrete shall be one of the following: 6.2.3.1. Portland cement only, 6.2.3.2. Portland blast-furnace slag cement only, 6.2.3.3. Portla
40、nd-pozzolan cement only, and 6.2.3.4. A combination of portland cement and fly ash wherein the proportion of fly ash is between 5 and 25 percent by weight of total cementitious material (portland cement plus fly ash). 6.3. AggregatesAggregates shall conform to M 6 and M 80 except that the requiremen
41、ts for gradation shall not apply. 6.4. Admixtures and BlendsAdmixtures and blends may be used with the approval of the owner. 6.5. Steel ReinforcementReinforcement shall consist of welded wire fabric conforming to M 55M/M 55 or M 221M/M 221. Longitudinal distribution reinforcement may consist of wel
42、ded wire fabric or deformed billet-steel bars conforming to M 31M/M 31, Grade 60. 6.6. Synthetic FibersPolypropylene fibers may be used, at the owners option, in concrete pipe as a nonstructural manufacturing material. Only Type III synthetic fibers designed and manufactured specifically for use in
43、concrete and conforming to the requirements of ASTM C 1116/C 1116M shall be accepted. 7. DESIGN 7.1. Design TablesThe box section dimensions, compressive strength of the concrete, and reinforcement details shall be as prescribed in Tables 1 or 2 and Figures 1 and 2, subject to the provisions of Sect
44、ion 11. Table 1 sections are designed for a cover range from 0 to 2 ft plus AASHTO HS20 live load conditions. Table 2 sections are designed for a cover range from 0 to 2 ft plus Interstate live load conditions. Criteria used to develop Tables 1 and 2 are given in the Appendix X1. 7.2. Modified and S
45、pecial DesignsThe manufacturer may request approval by the owner of modified designs that differ from the designs in Section 7.1; or special designs for sizes and loads other than those shown in Tables 1 and 2. 7.3. Placement of ReinforcementThe cover of concrete over the circumferential reinforceme
46、nt shall be 1 in. except in the outside top of the top slab, where it shall be 2 in., subject to the provisions of Section 11. The inside circumferential and longitudinal reinforcement shall extend into the male portion of the joint and the outside circumferential and longitudinal reinforcement shal
47、l extend into the female portion of the joint. The clear distance of the end circumferential wires shall be not less than 1/2in. or more than 2 in. from the ends of the box section. Reinforcement shall be assembled utilizing any combination of single or multiple layers of welded wire fabric. Common
48、reinforcement units may be used for both As2(or As3) and As4, and also for both As7(or As8) and As1, with the largest area requirement of each combination governing, bending the reinforcement 90 degrees at the corners, and waiving the extension requirements of Figure 2. See Figure 3. The welded wire
49、 fabric shall be composed of circumferential and longitudinal wires meeting the spacing requirements of Section 7.4 and shall contain sufficient longitudinal wires extending 2013 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4a M 273-6 AASHTO through the box se
