1026.7 Reinforced Concrete Pipe (RCP) Inspection Guide

This guide will assist in the inspection of all types and configurations of Reinforced Concrete Culvert (RCP) Pipe. Answer each question and take the action indicated for the answer given. If no condition is provided for a particular answer, move to the next question.

The inspector is responsible to confirm that this inspection guide is in accordance with current specifications.

Every lot should be visually inspected. The lot that appears to have the most defects, or a lot selected at random if all lots appear to be of equal quality, shall be inspected in greater detail to generally establish the Quality Control practices of the manufacturer. And at least one pipe per size offered in the lot shall be inspected in detail using this inspection guide. The manufacturer may provide the definition of a lot. If no definition is provided, a lot will be one day’s production. Or, if at the project, a lot shall be the entire quantity shipped.

If this inspection guide is used to inspect a rejected pipe, it shall be submitted with the notification to the manufacturer of the failure to meet specification.

Is this manufacturer approved for production of RCP pipe? (refer to Table 1026.5.1 Diameter Dimensional Tolerances (English)) If No, stop, the pipe is unacceptable.	Yes	No
Is the pipe accompanied by a bill of lading or delivery receipt at this location? If No, stop, the pipe is unacceptable.	Yes	No
Does the bill of lading or delivery receipt contain an itemized list of the sizes, classes, and lengths of pipe? If No, stop, the pipe is unacceptable.	Yes	No
Does the bill of lading or delivery receipt contain a MoDOT Pipe ID or is it accompanied by a Pipe Shipping Report Form? If No, stop, the pipe is unacceptable.	Yes	No
Is the pipe marked (in accordance with AASHTO M 170) with the pipe class and specification designation? If No, stop, the pipe is unacceptable.	Yes	No
Is the pipe marked (in accordance with AASHTO M 170) with the date of manufacture? If No, stop, the pipe is unacceptable.	Yes	No
Is the pipe marked (in accordance with AASHTO M 170) with the name or trademark of the manufacturer? If No, stop, the pipe is unacceptable.	Yes	No
Is the pipe marked (in accordance with AASHTO M 170) with the identification of the plant? If No, stop, the pipe is unacceptable.	Yes	No
Is the pipe marked (in accordance with AASHTO M 170) with a “Q Cast” stamp? (This is to certify the pipe was produced by an ACPA certified plant.) If No, stop, the pipe is unacceptable.	Yes	No
Are the markings indented or marked in some other permanent manner? If No, stop, the pipe is unacceptable.	Yes	No
If the pipe contains elliptical reinforcement, is one end section of the pipe marked on the inside and the outside of opposite walls along the minor axis of the elliptical reinforcement with the word “Top” or “Bottom” to designate the proper position when laid? If No, stop, the pipe is unacceptable.	Yes	No
Does the pipe include any fractures or cracks passing thorough the wall, except for a single end crack that does not exceed the depth of the joint? If Yes, stop, the pipe is unacceptable.	Yes	No
Does the pipe include any defects that indicate imperfect proportioning, mixing or molding? If Yes, stop, the pipe is unacceptable.	Yes	No
Does the pipe include any surface defects indicating honeycombed or open texture? If Yes, stop, the pipe is unacceptable.	Yes	No
Does the pipe include any damaged or unsatisfactorily manufactured ends that would prevent creating a satisfactory joint? If Yes, stop, the pipe is unacceptable.	Yes	No
Does the pipe include any continuous crack having a surface width of 0.01 in. or more and extending a length of 12 in. or more, regardless of position in the wall of the pipe? If Yes, stop, the pipe is unacceptable.	Yes	No
Is the inside diameter of the pipe within the permissible tolerances? (refer to Table 1026.5.1 Diameter Dimensional Tolerances (English) or Table 1026.5.2 Diameter Dimensional Tolerances (Maetric). If No, stop, the pipe is unacceptable.	Yes	No

The wall thickness shall not be less than that shown AASHTO by more than 5 percent or 3/16 in., whichever is greater. Pipe having localized variations in wall thickness exceeding these requirements will not be rejected if the three edge bearing strength and minimum steel cover requirements are met.

Is the wall thickness less than required by AASHTO and as described above? (Refer to AASHTO M 170, Tables 1 thru 5.) If Yes, stop, the pipe is unacceptable.	Yes	No
Is the under-run in length of the pipe more than 1/8 in. per foot or, regardless of overall length, more than ½ in.? If Yes, stop, the pipe is unacceptable.	Yes	No

1026.7.1 Lift Holes

If the pipe has been specified with rubber gasketed joints, does it contain lift holes? If No, skip this section.	Yes	No
If the pipe is 60 in. in diameter or less, are the lift holes larger than 2.5 in.? If Yes, stop, the pipe is unacceptable.	Yes	No
If the pipe is greater than 60 in. in diameter, are the lift holes larger than 3.5 in.? If Yes, stop, the pipe is unacceptable.	Yes	No

1026.7.2 Three-Edge Bearing Tests and Compressive Strength Tests

Either of the following tests shall be performed at the discretion of the engineer, but not less than specified herein. It is not necessary to perform both tests. One of the tests will suffice.

1026.7.2.1 Three-Edge Bearing Tests (AASHTO T 280)

One section of pipe of each size, class, and type is to be tested in accordance with AASHTO T 280.

For each diameter of pipe smaller than 66 in., one pipe of each size, class, and type shall be tested to the load, which produces a 0.01 in. crack, for each 3000 ft. offered for inspection, or at least once per calendar year. Frequency of testing to the ultimate load will be at the discretion of the engineer.

Pipe with diameters 66 in. or larger shall be tested to the load, which produces a 0.01 in. crack, for each 1000 ft. offered, regardless of the time it takes to manufacture 1000 ft. Frequency of testing to the ultimate load will be at the discretion of the engineer but at least once per 365 days. Testing will not be required at plants where pipe of these diameters is not manufactured for MoDOT, nor will pipe of these diameters be required to be manufactured solely for the purpose of testing.

Pipe, tested to the load, which produces a 0.01 in. crack, may still be accepted for use. The pipe must be identified as such by stenciling or marking inside the bell end of the barrel, “Pipe Tested” and stamping “OK-MoDOT” immediately after the word “Tested.”

Does the pipe support the D-load required by specification when loaded to produce a 1 ft. long, horizontal, 0.01 in. crack ? (Refer to AASHTO M 170, Tables 1 thru 5) If No, stop, the pipe is unacceptable.	Yes	No
Does the pipe support the D-load required by specification when loaded to ultimate load? (Refer to AASHTO M 170, Tables 1 thru 5) If No, stop, the pipe is unacceptable.	Yes	No

1026.7.2.2 Compressive Strength Tests

The compressive strength is to be determined by concrete cylinders in accordance with Sec 1026 and AASHTO T 23 or by cores drilled from the wall of the pipe in accordance with AASHTO T 280.

For pipe with diameters smaller than 66 in., the compressive strength of one pipe of each size, class and type shall be determined at least once per each 3000 ft. offered for inspection, or at least once per calendar year. Increased frequency of testing shall be at the discretion of the engineer.

For pipe with diameters of 66 in. or larger, the compressive strength shall be determined not less than once per 1000 ft. offered, but at least once per 365 days. Testing will not be required at plants where pipe of these diameters is not manufactured for MoDOT, nor will pipe of these diameters be required to be manufactured solely for the purpose of testing.

Is the compressive strength being determined by drilled cores? If Yes, proceed to Section 1.	Yes	No
Is the compressive strength being determined by concrete cylinders? If Yes, proceed to Section 2.	Yes	No

Section 1

Is the compressive strength of each of the initial cores tested equal to or greater than the design concrete strength? If No, drill two additional cores, from the same pipe, for each core with a compressive strength less than the design strength.	Yes	No
Is the average compressive strength of the three cores (or each group of three cores) equal to or greater than the design concrete strength, with no single core having less than 85 percent of the design strength? If Yes, the concrete is acceptable. If No, select two additional pipe sections at random for testing. Answer these questions for the new cores and continue through the following questions. This process may only be repeated once.	Yes	No
Do either of the additional two pipe sections not meet the requirements of the previous two questions? If Yes, the entire lot of concrete is rejected. Or the manufacturer may elect to core each pipe section of the remaining lot and have them accepted pipe by pipe.	Yes	No
Has the accepted pipe, from which cores were drilled, been plugged and sealed allowing it to still pass this inspection guide? If No, stop, the pipe is unacceptable.	Yes	No

Section 2

The concrete cylinders to be tested may be standard rodded concrete cylinders or cylinders compacted and cured in like manner as the pipe. No fewer than five test cylinders from a group (one day’s production of each concrete strength) of pipe sections should be prepared for testing.

Is the compressive strength of each cylinder of the group equal to or greater than the design strength? If No, proceed to the next question.	Yes	No
Is the average compressive strength of the group of cylinders equal to or greater than the design strength, with not more than 10 percent of the cylinders tested having a compressive strength less than the design strength, and no single cylinder tested having less than 80 percent of the design strength? If No, stop, the group (lot) of pipe is unacceptable.	Yes	No