Page 390 - Trenchless Technology Piping Installation and Inspection

340 Cha pte r Ei g h t

Inspection Guide for Pipe Ramming (PR)
Preinspection Plan Review

Review geotechnical and soil reports.
Ensure DOT / agency facilities and nearby utility information are shown on the
plans and profiles and that the proposed alignment does not interfere with them.

Note the minimum cover above the top of the pipe and below the pavement surface,
or ground elevation (for longitudinal installations outside the influence of the
roadway) is _____ ft.
Note proposed steel casing pipe characteristics:
Casing material yield strength ____ ksi.
Casing diameter _____________ in.
Overcut diameter ___________ in.
Casing wall thickness ________ in.
Casing spacers material ____________.
Spacer spacing ___________________.
Carrier material ___________________.
Carrier diameter ____________ in.

Note the inside diameter of the casing pipe, and the outside diameter of the carrier
pipe. The difference is _______ in. (Typical minimum is 6 in.)
Review contingency plan.
Review job-site layout including: distance from access pits to roadbed, proposed
sheeting and bracing, materials storage and fabrication area, safety devices (barrels,
guardrail, etc.), and dewatering pit locations.
Note unique or special items /circumstances: ___________________
Construction Inspection

Verify traffic control is consistent with the permit requirements, one call service
has been contacted, and the DOT / agency permit is on-site.
Verify job-site layout is consistent with the approved plans, especially the alignment
of the pipe and machine.

Verify continuous monitoring records indicate bearing and grade of the leading edge
of the pipe is consistent with the approved plans, dewatering effort is satisfactory, soil
volume removed is consistent with projection, and that workers understand the
contingency plan.
Verify pipe characteristics are consistent with permit requirements.

Verify the casing pipe is new steel with smooth interior and exterior surfaces, is used
within the entire influence area of the roadbed, has clean and square ends, joints are
watertight, defective pipe is not used, and damaged pipe is removed.

FIGURE 8.21 Sample checklist for inspection of pipe ramming operations.