1、Standard Method of Test for Steel Welded Wire Reinforcement, Plain, for Concrete AASHTO Designation: M 55M/M 55-09 (2013) ASTM Designation: A185/A185M-07 American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001 TS-4g M 55M/M 5
2、5-1 AASHTO Standard Method of Test for Steel Welded Wire Reinforcement, Plain, for Concrete AASHTO Designation: M 55M/M 55-09 (2013) ASTM Designation: A185/A185M-07 1. SCOPE 1.1. This specification covers welded wire reinforcement to be used for the reinforcement of concrete. Note 1Welded wire for c
3、oncrete reinforcement has been described by various terms: welded wire fabric (WWF), fabric, and mesh. The wire reinforcement industry prefers the term “welded wire reinforcement” or WWR as being more representative of the range of products being manufactured. Therefore, the term “welded wire fabric
4、” has been replaced with the term “welded wire reinforcement” in this specification and in related specifications. 1.2. This specification is applicable for orders in either SI units (M 55M) or in inch-pound units (M 55). SI units and inch-pound units are not necessarily equivalent. Inch-pound units
5、 are shown in brackets in the text for clarity but they are the applicable values when the material is ordered to M 55. The values stated in each system are not exact equivalents; therefore, each system must be used independently of the other. Combining values may result in nonconformance with the s
6、pecification. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standard: M 32M/M 32, Steel Wire, Plain, for Concrete Reinforcement 2.2. ASTM Standards: A700-05, Standard Practices for Packaging, Marking, and Loading Methods for Steel Products for Shipment (withdrawn 2014) Adjunct to A185, Steel Welded Wire Reinf
7、orcement, Plain, for Concrete and A 497 Steel Wire, Deformed, for Concrete Reinforcement: ADJA0185 2.3. Military Standard: MIL-STD-129, Marking for Shipment and Storage 2.4. Federal Standard: Fed. Std. No. 123, Marking for Shipment (Civil Agencies) 2015 by the American Association of State Highway a
8、nd Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4g M 55M/M 55-2 AASHTO 3. TERMINOLOGY 3.1. Description of Terms Specific to This Standard: 3.1.1. convoluted wirewhen wire for welded reinforcement is formed into a sinusoidal wave shape, it is commonly
9、referred to as convoluted wire. The wire is used in the manufacture of cages for certain applications of concrete pipe reinforcing. 3.1.2. welded wire reinforcementas used within the scope and intent of this specification, designates a material composed of cold-drawn steel wire, as drawn or galvaniz
10、ed, fabricated into sheets or rolls by the process of electric-resistance welding. The finished material shall consist essentially of a series of longitudinal and transverse wires arranged substantially at right angles to each other and welded together at points of intersection. 4. ORDERING INFORMAT
11、ION 4.1. It shall be the responsibility of the purchaser to specify all requirements that are necessary for the manufacture and delivery of the welded wire reinforcement under this specification. Such requirements to be considered include, but are not limited to, the following: 4.1.1. Quantity (mass
12、 or square area); 4.1.2. Name of material (welded wire reinforcement for concrete reinforcement); 4.1.3. Wire spacings and sizes; 4.1.4. Minimum yield strength if Supplement S1 of M 32M/M 32 applies; 4.1.5. Yield strength measurement; the purchaser shall have the options described in M 32M/M 32 unde
13、r the Inspection section (Section 11.3); 4.1.6. Exclusion of oversteeling, if required (Section 9.4.2); 4.1.7. Length and width of sheets or rolls; 4.1.8. Packaging (Section 16); 4.1.9. Request for outside inspection (if not requested, Section 15.1 applies); and 4.1.10. AASHTO designation and year o
14、f issue. Note 2A typical ordering description is as follows: 930-m2welded wire reinforcement for concrete reinforcement, 100 300-W15 W6 in flat sheets, 2.4 m wide 6.1 m long, in secured lifts, to M 55M. 10,000-ft2welded wire reinforcement for concrete reinforcement, 4 12 W15 W6 in flat sheets, 96 in
15、. wide 240 in. long, in secured lifts, to M 55. 5. MATERIALS 5.1. The wire used in the manufacture of welded wire reinforcement shall conform to M 32M/M 32 and its Supplement S1 if so ordered. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplica
16、tion is a violation of applicable law.TS-4g M 55M/M 55-3 AASHTO 5.2. Welded wire reinforcement shall be furnished either in flat sheets or in rolls, as specified by the purchaser. 6. MANUFACTURE 6.1. The wires shall be assembled by automatic machines or by other suitable mechanical means that will a
17、ssure accurate spacing and alignment of all members of the finished welded wire reinforcement. 6.2. Longitudinal and transverse members shall be securely connected at every intersection by a process of electrical-resistance welding, which employs the principle of fusion combined with pressure. 6.3.
18、Wire of proper yield strength and quality when fabricated in the manner herein required shall result in a strong, serviceable, mat-type product having substantially square or rectangular openings. It shall be fabricated and finished in a workmanlike manner and shall conform to this specification. No
19、te 3A variation of manufacturing includes the application of one or more longitudinal convoluted wires at one edge of reinforcement for concrete pipe reinforcing cages. This shape allows the cage ends to be expanded to a larger diameter to accommodate the bell-shaped ends of concrete pipe. 7. MECHAN
20、ICAL PROPERTY REQUIREMENTS 7.1. TensileWire for the production of welded wire reinforcement is described in M 32M/M 32. Tensile tests may be made on wire cut from the welded wire reinforcement and tested either across or between the welds; no fewer than 50 percent shall be across the welds. Tensile
21、tests across the weld shall have the welded intersection located approximately at the center of the wire being tested and the cross wire forming the welded intersection shall extend approximately 25 mm 1 in. beyond each side of the welded intersection. Note 4Tensile, reduction of area, and bend test
22、ing are normally done at the time the wire is drawn. The manufacturers finished product shall meet the requirements of this specification and M 32M/M 32. 7.2. Reduction of AreaThe ruptured section of the tensile specimen shall be measured to determine this property. In the case of a specimen that ha
23、s been tested across a weld, the measurement shall be made only when rupture has occurred at a sufficient distance from the center of a weld to permit an accurate measurement of the fractured section. The wire shall meet the minimum reduction of area requirements of M 32M/M 32. 7.3. Bend TestThe wir
24、e shall withstand the bend test as described in M 32M/M 32 and shall be performed on a specimen taken from between the welds. 7.4. Weld Shear StrengthThe weld shear strength between longitudinal and transverse wires shall be tested as described in Section 8. The minimum average shear value, in newto
25、ns, shall not be less than 241, multiplied by the nominal area of the larger wire in square millimeters in pounds-force shall not be less than 35,000, multiplied by the nominal area of the larger wire in square inches, where the smaller wire is not less than size W1.2 and has an area of 40 percent o
26、r more of the area of the larger wire. Typical examples of the 40 percent or more wire size differential area follow: 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4g M 55M/M 55-4 AASHTO Larger Smal
27、ler Size No. W20 Size No. W8 Size No. W15 Size No. W6 Size No. W10 Size No. W4 7.4.1. Reinforcement having a relationship of longitudinal and transverse wires other than those covered in Section 7.4 shall not be subject to the weld shear requirement. 7.4.2. Weld shear tests for determination of conf
28、ormance to the requirements of Section 7.4 shall be conducted using a fixture as described in Section 8. 7.4.3. Four welds selected at random from the specimen described in Section 11.2 shall be tested for weld shear strength. The transverse wire of each test specimen shall extend approximately 25 m
29、m 1 in. on each side of the longitudinal wire. The longitudinal wire of each test specimen shall be of such length below the transverse wire so as to be adequately engaged by the grips of the testing machine. It shall be of such length above the transverse wire that its end shall be above the center
30、line of the upper bearing of the testing device. 7.4.4. The material shall be deemed to conform to the requirements for weld shear strength if the average of the four samples complies with the value stipulated in Section 7.4. If the average fails to meet the prescribed value, all the welds across th
31、e specimen shall then be tested. The reinforcement will be acceptable if the average of all weld shear test values across the specimen meets the prescribed minimum value. 8. WELD SHEAR TEST APPARATUS AND METHODS 8.1. As the welds in welded wire reinforcement contribute to the bonding and anchorage v
32、alue of the wires in concrete, the weld acceptance tests shall be made in a weld tester that stresses the weld in a manner similar to which it is stressed in concrete. In order to accomplish this, the vertical wire in the weld tester shall be stressed in an axis close to its centerline. Also, the ho
33、rizontal wire shall be held closely to the vertical wire, and in the same relative position, so as to prevent rotation of the horizontal wire. When the welded wire reinforcement is designed with different wire sizes, the larger diameter wire is the “vertical wire” when tested (see Figure 1).1 2015 b
34、y the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4g M 55M/M 55-5 AASHTO Figure 1Welded Wire Reinforcement Weld Tester 8.2. Figure 1 shows the details of a typical weld tester together with two anvils that ma
35、ke it possible to test welds for wire up to 16 mm 5/8in. in diameter. This weld tester can be used in most tension testing machines and should be hung in a ball-and-socket arrangement at the center of the machine. This, or a similarly effective fixture designed on the same principle, is acceptable.
36、8.3. Test specimens should be inserted through the notch in the anvil using the smallest notch available in which the vertical wire will fit loosely. The vertical wire shall be in contact with the surface of the free rotating rollers while the horizontal wire shall be supported by the anvil on each
37、side of the slot. The bottom jaws of the testing machine shall grip the lower end of the vertical wire and the load shall be applied at a rate of stressing not to exceed 690 MPa/min 100,000 psi/min. 9. DIMENSIONS, MASS, AND PERMISSIBLE VARIATIONS 9.1. WidthThe width of welded wire reinforcement shal
38、l be considered to be the center-to-center distance between outside longitudinal wires. The permissible variation shall not exceed 13 mm 1/2in. greater or less than the specified width. In case the width of flat sheets or rolls is specified as the overall width (tip-to-tip length of cross wires), th
39、e width shall not vary more than 25 mm 1 in. from the specified width. 9.2. LengthThe overall length of flat sheets, measured on any wire, may vary 25 mm 1 in. or 1 percent, whichever is greater. 9.3. Overhang of the transverse wires shall not project beyond the centerline of each longitudinal edge
40、wire more than a distance of 25 mm 1 in. unless otherwise specified. When transverse wires are specified to project a specific length beyond the centerline of a longitudinal edge wire, the permissible variation shall not exceed 13 mm 1/2in. greater or less than the specified length. 9.4. The permiss
41、ible variation in diameter of any wire in the finished welded wire reinforcement shall conform to the tolerances prescribed for the wire before fabrication in M 32M/M 32, with the following exceptions: 2015 by the American Association of State Highway and Transportation Officials.All rights reserved
42、. Duplication is a violation of applicable law.TS-4g M 55M/M 55-6 AASHTO 9.4.1. Because of the mechanical characteristics of fabricating welded wire reinforcement, the out-of-round requirements shall not apply. 9.4.2. Unless otherwise precluded by the purchaser in Section 4.1, the manufacturer will
43、be permitted to apply oversized wire (not undersized). The size differential shall not exceed two “W” size increments on sizes W8 and smaller and four “W” size increments on sizes larger than W8. A “W” size increment is a whole number increment, for example, W5 to W6, or W5.4 to W6.4, etc. In all ca
44、ses in which such oversteeling is practiced, the producer shall identify the welded wire reinforcement with the style originally ordered. 9.5. The average spacing of wires shall be such that the total number of wires contained in a sheet or roll is equal to or greater than that determined by the spe
45、cific spacing, but the center-to-center distance between individual members may vary not more than 6.4 mm 1/4in. from the specified spacing. It is understood that sheets of welded wire reinforcement of the specified length may not always contain an identical number of transverse wires and, therefore
46、, may have various lengths of longitudinal overhang. 10. WORKMANSHIP, FINISH, AND APPEARANCE 10.1. Wire of proper grade and quality, when fabricated in the manner herein required, shall result in a strong, serviceable, mesh-type product having substantially square or rectangular openings. It shall b
47、e fabricated and finished in a workmanlike manner, as determined by visual inspection, and shall conform to this specification. 11. SAMPLING 11.1. Test specimens for testing mechanical properties shall be obtained by cutting from the finished welded wire reinforcement a full width section, of suffic
48、ient length to perform testing described in Sections 7.1 and 7.2. 11.2. Test specimens for determining weld shear properties shall be obtained by cutting from the finished welded wire reinforcement, a full width section of sufficient length to perform testing described in Section 7.4. 11.3. Measurem
49、ents for conformance to dimensional characteristics shall be made on full sheets or rolls. 11.4. Any test specimen exhibiting obvious imperfections shall be discarded and another specimen substituted. 12. NUMBER OF TESTS 12.1. One test for conformance to tensile strength and bend requirements, and one check for conformance to dimensional characteristics shall be made for each 7000 m275,000 ft2 of welded wire reinforcement or remaining fraction thereof. 12.2. One test for conformance to weld shear strength requirement sh
