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Construction and Inspection for Cur ed-in-Place Pipe     299


          Testing Issues
          CIPP samples must be tested based on the ASTM guidelines previ-
          ously mentioned. If testing results fall short of required flexural
          modulus or thickness requirements, the required stiffness and actual
          stiffness of the lining samples will be compared. After comparison, if
          the average of actual stiffness is greater than 94 percent of the required
          stiffness, the pipe will be accepted, but marked as noncompliant and
          a deductive penalty proportional to the stiffness deficiency can be
          assessed against the contractor. A change order will be issued for the
          deductive penalty, in proportion to the deficiency, and the remaining
          balance for the CIPP section will be paid to the contractor. If the aver-
          age of actual stiffness for the CIPP section is less than 94 percent of the
          required stiffness, the CIPP section will not be accepted and the con-
          tractor will be required to install a second liner over the first liner to
          compensate for the deficiency, at no extra cost to the project owner.
          Full payment for the CIPP section will be issued to the contractor after
          the second liner is properly installed and accepted.  Assuming an
          acceptable second liner is properly installed, no deductive penalty will
          be imposed against the contractor.∗
             To identify every defective condition and to suggest every correc-
          tive measure or penalty is beyond scope of this book. This section is
          only intended as a guide to aid in identifying physical conditions of
          the installation, applying appropriate corrective measures, and assign-
          ing deductive penalties for defective installations, which should all
          be included in the bid and contract documents. This way the contrac-
          tors know, before the bidding and start of the project, what expected
          quality measures are and possible outcomes if these quality measures
          are not met. This way, many quality problems, disputes, and potential
          litigations may be avoided. The final decision for application, enforce-
          ment, and final acceptance will ultimately be made by the owner’s
          project/construction manager or the city engineer on a case by case
          basis and as stipulated in the contract documents. Using codes pro-
          vided in Table 7.8, Table 7.10 presents a summary of potential CIPP
          defects, suggested acceptable tolerances, and possible repaired types
          that may be required. Figure 7.8 illustrates potential CIPP defects.


          ∗The measured wall thickness has much more impact upon buckling resistance
          than the flexural modulus. Its value adjusts the buckling resistance by its cube
          power and is not directly proportional. Design engineers and project owners
          should be cautioned that contractors may submit higher bids, or choose not
          to submit a bid, if the contract contains unjustified quality requirements, low
          tolerance expectations, and possibilities of penalties or rework. Including or
          not including such language in the contract and justification of level of quality
          required needs to be evaluated based on project owner’s needs, on the true
          project hydraulic, structural, and performance requirements, and must be
          evaluated in case by case basis using judgment of a knowledgeable professional
          engineer.
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