Category:1031 Clay Drain Tile

This article establishes procedures for inspecting, accepting and reporting of clay drain tile. Refer to Sec 1031 for more information.

1031.1 Apparatus

(a) Rule with suitable graduations to accurately measure the material to be inspected.

(b) OK – MoDOT stamp.

(c) Weather resistant marking materials.

1031.2 Procedure

All requirements for clay drain tile are specified in AASHTO M 179. The bases of acceptance are measurement and visual examination of the finished tile; three-edge bearing test; and absorption. Absorption may be waived provided the tile meets a freezethaw test as specified in AASHTO M 179. If a small quantity of a size and class of tile is required for a project and tests have not been observed, the tile may be accepted by manufacturer's certification to AASHTO M 179. This method of acceptance is only to be used until observation of tests can be arranged.

Random measurements are to be made of the diameter, length and wall thickness. Visual examination of clay drain tile is to be performed on each piece offered for use on MoDOT projects. As the tile are inspected, each accepted piece is to be marked with an "OK-MoDOT" stamp and each rejected piece is to be marked with a small, filled circle of orange paint on the inside, near the downstream end of the tile, when it can be determined. Visual examination and marking may be performed either at the source or at destination.

Three-edge bearing tests shall be observed on each size and class of pipe furnished for MoDOT projects. Samples shall be selected and prepared for testing in accordance with AASHTO M 179. The tests are to be performed in accordance with AASHTO T281 and at a frequency of approximately every two years or as deemed necessary.

Absorption samples are to be taken from tile broken in three-edge bearing and submitted to the Central Laboratory for testing. Size of sample shall be as specified in AASHTO T 281. SiteManager is to be used when submitting samples to the Central Laboratory and the test for which the sample is being submitted shall be indicated.

1031.3 Report (Reords)

All tile inspected shall be reported in SiteManager acceptance or rejection. Acceptance reports shall contain a statement in the Free Form test of the report such as “Three-edge bearing and absorption test results on file in the District Materials Office,” or “Accepted on the basis of manufacturer’s certification on file in the District Office.” Rejection reports shall contain a brief explanation of causes of rejection.

Three-edge bearing tests are to be reported on a form similar to Table 1030, Report of Tests on Clay Pipe. The district shall provide its own forms. The Operations Engineer will review the test results prior to filing in the district office.

Distribution of reports for materials purchased under a MoDOT purchase order is to be as described in 1101 Maintenance Materials. A report created for a MoDOT purchase order shall at least include the purchase order number on the “Other” tab and the number pieces, total length of tile inspected and an acceptance or rejection statement in the Free Form test.