AASHTO M245-20 pdf free download

AASHTO M245-20 pdf free download.Corrugated Steel Pipe, Polymer- Precoated, for Sewers and Drains.
6.4. Hardware for Coupling Bands- _Bolts and nuts for coupling bands shall conform to the following requirements (see Table 2). Bolts, nuts, and other threaded items used with coupling bands shall be zinc coated by one of the following processes: hot-dip process as provided in M 232M/M 232; electroplating process as provided in ASTM B633, Class Fe/Zn 8; or mechanical process as provided in ASTM B695, Class 8. Other hardware items used with coupling bands shall be zinc coated by one of the following processes: hot-dip process as provided in M 232M/M 232; electroplating process as provided in ASTM B633, Class Fe/Zn 25; or mechanical process as provided in ASTM B695, Class 25. 6.5. Gaskets- If gaskets are used in couplings, they shall be a band of expanded rubber meeting the requirements of ASTM D1056 for the“RE” closed cell grades, or O-rings meeting the requirements of ASTM C443. 7. FABRICATION 7.1. General Requirements- -Pipe shall be fabricated in full circular cross section except for Type IIA, which is described in Section 8.4. .7.1.1. Type I pipe shall have annular corrugations with lap joints fastened with rivets or shall have helical corrugations with a continuous lock seam extending from end to end of each length of pipe. The type of fabrication used shall be the option of the fabricator unless otherwise specified. 7.1.2. Type IA pipe shall be fabricated with a smooth liner and helically corrugated shell integrally attached at helical lock seams extending from end to end of each length of pipe. The shell shall have corrugations of nominal 68-, 75- or 125 -mm pitch.
7.1.3. Type IR pipe shall be fabricated with helical ribs projecting outward with a continuous lock seam extending from end to end of each length of pipe. 7.2. Corrugations- The corrugations shall be either annular or helical as provided in Section 7.1. The direction of the crests and valleys of helical corrugations shall not be less than 60 degrees from the axis of the pipe for pipe diameters larger than 525 mm and not less than 45 degrees from the axis for pipe diameters of 525 mm and smaller. 7.2.1. For Type I and IA pipe, corrugations shall form smooth continuous curves and tangents. The dimensions of the corrugations shall be in accordance with Table 3 for the size indicated in the order, except if the depth measurement of one or more corrugations is less than the minimum depth in Table 3, the depth of all corrugations between adjacent seams shall be measured and the values of Table 4 for minimum average depth and minimum corrugation depth shall apply. Note 3- -Inspection frequently consists of measurement of the depth of one or a few corrugations. If such measurement indicates insufficient depth, application of the requirements in Table 4 provides for acceptance where greater depth of some corrugations compensates for lack of depth of others. These measurements would normally be made at one location between seams on a length of pipe.
7.2.2. For Type IR pipe, the corrugations shall be essentially rectangular ribs projecting outward from the pipe wall. The dimensions and spacing of the ribs shall be in accordance with Table 5 for the size indicated on the order. For the 292-mm rib spacing, if the sheet between the ribs does not include a lock seam, a stiffener shall be included midway between the ribs. This stiffener shall have a nominal radius of 6.4 mm and a minimum height of 5.1 mm toward the outside of the pipe.
AASHTO M245-20 pdf download.