1023Structural Plate Pipe and Pipe-Arches

1023.1 Scope. This specification covers corrugated galvanized steel structural plates intended for use in

construction of pipe and pipe arches. The plates shall consist of corrugated galvanized metal and shall be curved such that the plates can be bolted together to form a structure of the specified shape and size.

1023.2 Basis of Acceptance. The basis of acceptance will be in accordance with Sec 1020.2, Sec 1020.5, and as

specified herein.

1023.3 Material. Corrugated galvanized steel structural plate for structural plate pipe and pipe arches shall be in

accordance with AASHTO M 167, with the following modifications.

1023.3.1 Corrugations. The radii of curvature of the corrugations shall be at least one-half the depth of the

corrugations. The corrugations shall have a depth of 2 inches and a pitch of 6 inches. The depth of corrugations shall not underrun the specified depth by more than 5 percent, and the pitch of the corrugations shall not deviate from the specified depth by more than 1/4 inch.

1023.3.2 Spelter Coating. The spelter coating shall be free from injurious defects such as blisters, flux and

uncoated spots. For testing the weight of spelter coating and for chemical analysis, if required, the manufacturer shall take two samples for each 100 plates of each thickness of a shipment or fraction thereof. The samples may be obtained from a piece approximately 3 inches square, cut from a corner of a plate or from a coupon approximately 6 inches square attached to the center of one edge of the plate prior to galvanizing. The coupon shall be of the same thickness and base metal as the plate to which the coupon is attached. One sample shall be retained for the engineer for QA purposes and one sample shall be tested by the manufacturer. If the result of a test for weight of coating for any sample is not in accordance with AASHTO M 167, an additional sample shall be cut for tests from each of two other plates in the lot represented by the nonconforming sample. All original samples and samples for retest shall be in accordance with AASHTO M 167, or the entire shipment will be rejected. At the option of the engineer, the material may be accepted or rejected on the basis of magnetic gauge results, except at the request of the contractor or manufacturer, plates rejected by magnetic gauge results will be sampled as specified above.

1023.3.3 Accepted Brands of Metal. No metal will be accepted under these specifications until after the

manufacturer's certificate and guarantee have been approved by the engineer.

1023.3.3 1 Manufacturer's Certificate. The manufacturer of the structural plate identified by the

manufacturer's mark shall file with Construction and Materials, a certificate setting forth the name of the manufacturer, the base metal manufacturer, the specified chemical composition and a typical or average analysis showing the percent of sulfur, copper and any other elements specified in Table I of AASHTO M 167. The certificate shall be sworn to for the manufacturer by a person having legal authority to bind the company. Mismarking or other misrepresentation by the manufacturer will be considered sufficient reason to discontinue acceptance under these specifications. Notice sent to the manufacturer of the discontinuance of acceptance will be considered to be notice to all companies handling that particular manufacturer's product.

1023.3.3 2 Manufacturer's Guarantee. The manufacturer of the structural plate shall submit with the

certificate a guarantee providing that all structural plate furnished is in accordance with the specifications, shall bear the manufacturer's identification mark and shall be replaced without cost when not in accordance with the specified analysis, sheet thickness or spelter coating. The guarantee shall be so worded as to remain in effect as long as the manufacturer continues to furnish the material.

1023.3.4 Bolts and Nuts for Connecting Plates.

1023.3.4 1 Bolts for connecting plates shall be 3/4 inch in diameter and shall be in accordance with ASTM A

449. Nuts shall be in accordance with ASTM A 563, Grade C. Bolts, nuts and washers shall be galvanized in accordance with ASTM F2329, or the bolts, nuts and washers may be mechanically galvanized. If mechanically galvanized, the coating thickness, adherence and quality requirements shall be in accordance with ASTM B695, Class 55. Except as specified herein, bolts and nuts shall meet the dimension requirements of ANSI B18.2.1 for heavy hex bolts and ANSI B18.2.2 for heavy hex nuts. The bearing surface of both bolts and nuts shall be symmetrically shaped to a one-inch radius spherical surface. The maximum height of the wrench flats on bolts and thickness of nuts shall be within the limits specified in ANSI B18.2.1 and ANSI B18.2.2, respectively. Bolt lengths shall be such as to result in at least "full nuts" when tightened in place. The bolts and nuts may be sampled and tested before erection, or the bolts, nuts and washers may be accepted on certified mill tests by the manufacturer.

1023.3.4 2 Other fasteners may be used if the fasteners:

1023.4 Manufacture. Plates shall be connected by bolts at longitudinal and circumferential seams. Joints shall

be staggered such that no more than three plates come together at any one point. Plates shall be furnished in standard sizes to permit structure length increments of 2 feet. The size and shape of the plates shall be such that the finished structure will have the dimensions shown on the plans or as specified herein and the circumferential or peripheral transverse seams will be staggered at least one foot, except that the engineer may permit the seams in adjacent plates used for construction of beveled or skewed ends to be continuous. At least four bolts shall be used per foot of longitudinal seam, unless a greater number is specified on the plans, staggered in two rows 2 inches apart, with one row in the valleys and one row on the crests of the corrugations. Bolts along circumferential seams shall be spaced no more than 10 inches apart. The distance from the center of bolt hole to the edge of the plate shall be no less than 1.75 times the diameter of the bolt. The diameter of the bolt holes for the longitudinal seams, except holes at corners of plates, shall not exceed the diameter of the bolts by more than 1/4 inch. The major axis of the holes for transverse seams, including the holes at the corners of the plates, shall not exceed the diameter of the bolt by more than 1/2 inch and the average of the major and minor axis shall not exceed the diameter of the bolt by more than 1/4 inch.

1023.4.1 Circular Pipe. A manufacturing tolerance of 3 inches will be permitted in the diameter of the pipe.

The thickness of metal to be used for each structure will be specified in the contract. The plates shall be prominently marked to show the position in which the plates are to be placed in the structure.

1023.4.2 Pipe-Arch. Plates for a pipe-arch shall form a cross-section made up of four circular arcs tangent to

each other at the arcs’ junctions and symmetrical about the vertical axis. The top shall be an arc of no more than 180 degrees or no less than 155 degrees. The bottom shall be an arc of no more than 50 degrees or no less than 10 degrees. The top shall be joined at each end to the bottom by an arc of no more than 87.5 degrees or no less than 75 degrees. The radius of corner arcs shall be between 16 and 21 inches for Type C-29 and smaller sizes, and between 29 and 33 inches for Type C-30 and larger sizes. The dimensions of structural plate pipe-arch shall be as specified below, subject to a manufacturing tolerance of two percent plus one inch. The thickness of metal to be used for each structure will be specified in the contract. Structural Plate Pipe-Arch English TypeArea, Sq Ft Span, Ft-In. Height, Ft-In. TypeArea, Sq Ft Span, Ft-In. Height, Ft-In. C-1 22 6-1 4-7 C-28 105 14-10 9-1 C-2 24 6-4 4-9 C-29 109 15-4 9-3 C-3 26 6-9 4-11 C-30 98 13-3 9-4 C-4 28 7-0 5-1 C-31 102 13-6 9-6 C-5 31 7-3 5-3 C-32 106 14-0 9-8 C-6 33 7-8 5-5 C-33 110 14-2 9-10 C-7 35 7-11 5-7 C-34 115 14-5 10-0 C-8 38 8-2 5-9 C-35 119 14-11 10-2 C-9 40 8-7 5-11 C-36 124 15-4 10-4 C-10 43 8-10 6-1 C-37 129 15-7 10-6 C-11 46 9-4 6-3 C-38 133 15-10 10-8 C-12 49 9-6 6-5 C-39 138 16-3 10-10 C-13 52 9-9 6-7 C-40 143 16-6 11-0 C-14 55 10-3 6-9 C-41 148 17-0 11-2 C-15 58 10-8 6-11 C-42 153 17-2 11-4 C-16 61 10-11 7-1 C-43 158 17-5 11-6 C-17 64 11-5 7-3 C-44 163 17-11 11-8 C-18 67 11-7 7-5 C-45 168 18-1 11-10 C-19 71 11-10 7-7 C-46 174 18-7 12-0 C-20 74 12-4 7-9 C-47 179 18-9 12-2 C-21 78 12-6 7-11 C-48 185 19-3 12-4 C-22 81 12-8 8-1 C-49 190 19-6 12-6 C-23 85 12-10 8-4 C-50 196 19-8 12-8 C-24 89 13-5 8-5 C-51 202 19-11 12-10 C-25 93 13-11 8-7 C-52 208 20-5 13-0 C-26 97 14-1 8-9 C-53 214 20-7 13-2 C-27 101 14-3 8-11 …. …. …. ….

1023.4.3 Beveled Ends. When specified on the plans, end plates for forming beveled ends shall be shaped to

produce the specified slope in the finished structure. Burnt edges shall be free from oxide and burrs, and shall present a workmanlike finish. Any edges cut after galvanizing shall be completely covered with two coats of single component inorganic zinc or organic zinc-rich paint, meeting the approval of the engineer. Legible identification marks shall be placed on each part plate to designate the plate’s proper position in the structure.

1023.5 Workmanship. All plates shall show careful and finished workmanship. Among others, the following

defects are specified as constituting poor workmanship, and the presence of any or all of these defects in an individual plate or in general in any shipment, will be considered sufficient cause for rejection:

1023.6 Assembly Instructions and Drawings. The contractor shall provide the engineer with detailed assembly

instructions and drawings for each structural plate pipe or pipe-arch prior to the installation of these structures.

1023.7 Repair of Galvanizing. Spelter coating damaged in the field shall be repaired by hot-dip galvanizing,

the metallizing process as specified in Sec 1020 or by the zinc alloy stick method in accordance with Sec 1081, except that in instances of minor damage, the engineer may permit repair by painting with two coats of single component inorganic zinc or organic zinc-rich paint. The paint and application shall meet the approval of the engineer.