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298     Cha pte r  Se v e n


      Condition of Pipe   Design Parameters          Liner Thickness
      Partially deteriorated  Groundwater level increases  Increases
                          Ovality increases          Increases
      Fully deteriorated  Groundwater level increases  Increases
                          Soil cover increases       Increases
                          Ovality increases          Increases
                          Soil modulus increases     Decreases

     TABLE 7.9  Factors Affecting Design of CIPP


          and collapse due to soil and live loads. The resin and the lining tube
          make a composite material to determine the design thickness of the
          CIPP. The types of resins have been described in Sec. 7.3. There are
          generically two types of lining tubes––nonreinforced and reinforced
          liners. The reinforced liners can be divided into fiberglass and carbon
          fiber laminates.
             Creep causes the CIPP to change shape, reducing its capability to
          resist external pressures. Factors influencing the design of a liner
          include physical properties of lining technology, and site and project
          specific conditions as shown in Table 7.9. The pipe wall thickness
          design is based on the anticipated effects on pipeline creep due to
          external loads over a 50-year period as specified by ASTM F1216-09,
          Eqs. X1.1 and X1.3. See Sec. 2.7 for sample CIPP design calculations.

          Quality Issues
          This section describes a suggested method for addressing CIPP qual-
          ity issues. First, the project inspector will review CCTV post video
          within two weeks of submittal by the contractor. In the event the
          inspector finds that a corresponding tolerance level has been
          exceeded, the inspector will flag the defect and handover the CCTV
          post video to the project manager representing the owner or the city
          engineer for secondary review. If the project manager agrees that the
          defect is in excess of acceptable tolerance levels, he or she will deter-
          mine acceptable remedies to correct the defects at no extra cost to the
          project owner. If the contractor chooses not to correct the defects, a
          deductive penalty can be imposed against the contractor. Once the
          corrective work has been performed by the contractor to the satisfac-
          tion of the project manager and the inspector, full payment for the
          CIPP must be issued. In the event the contractor chooses to accept
          the penalty deduction stipulated in the contract rather than to correct
          the defect, a change order will be issued for the deduction and the
          remaining balance for the subject CIPP installation will be paid to
          the contractor.
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