Proposed Practice for Alternative Bidding of Highway Drainage Systems (2015)

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67 Installation, Maintenance, and Tracking One of the main objectives of the Recommended Practice is to encourage highway agencies to allow contractors to bid on a wider range of alternative pipe products and systems. With- out an associated appropriate and adequate post-installation inspection protocol, the risk of premature failure of pipe systems will increase. In this context, post-installation inspec- tion is not an optional extra for the Recommended Practice and must be seen as an essential component of implementa- tion. All the pipe system evaluation components within the Recommended Practice are based on the assumption that the pipe system was installed in compliance with agency specifications. Phase 5 of the Recommended Practice describes recom- mended steps and actions related to overall quality control, inspection, and tracking. Recommended actions for the five main steps in this phase are described in the following subsections. 13.1 Material and Construction Quality Assurance 13.1.1 Material Quality Assurance The standard of practice includes checks of all construction materials for conformance with the relevant AASHTO and state agency standards. Qualification of manufacturer and manufac- turing facility should be performed, together with review of certificates. Inspection of deliveries, which may include inspec- tion of identification markings, date of manufacture, shipping papers, diameter, net length, evidence of poor workmanship, damage during shipping or handling, and measurement of surface cracks, should also be performed. 13.1.2 Construction Quality Assurance Federally funded roadway construction projects are sup- posed to be performed in accordance with AASHTO stan- dards, in particular the AASHTO LRFD Bridge Construction Specifications. Inspection of the pipe system materials and workmanship during construction allows corrections to be made in assembly and backfill practices before construction is complete, and is of particular importance for deeply buried and high traffic instal- lations. The timing and frequency of such inspections should depend on the significance of the structure and depth of fill. In general, inspections should be conducted when materials arrive at the job site, during pipe installation, during backfilling, and before construction of final finishes. Inspections during construction may include examination of the following: • Foundation material • Trench geometry and dimensions • Groundwater conditions • Bedding material • Line and grade • Assembly techniques • Structure backfill and compaction methods • Joint assembly and materials • Pipe deflection (during construction) • Damage to pipe coatings 13.2 Post-Installation Inspection and Approval Different pipe materials may require different post- installation inspection and approval procedures due to the inherent differences in the modes of material behavior. Pipe materials are recommended to be inspected in accordance with the appropriate chapter of the AASHTO LRFD Bridge Con- struction Specifications: • Metal Pipe—Chapter 26 • Concrete Pipe—Chapter 27 • Thermoplastic Pipe—Chapter 30 C H A P T E R 1 3

68 13.3 Long Term Inspection and Maintenance Inspection of drainage pipe systems should be performed in accordance with the FHWA Culvert Inspection Manual (1986). NCHRP Project 14-26, Culvert and Storm Drain System Inspection Manual, is revising this guidance and is expected to be complete in fall 2015. 13.3.1 Tracking of Actual Performance Collection of performance data will assist designers, researchers, and policy makers to refine durability evalu- ation models and pipe selection criteria. Collection of this data should be performed using the guidance from the Asset Management Data Collection Guide (AASHTO 2006). At a minimum the following information on each culvert should be recorded during each major inspection: • Environmental parameters of surface water flow in the system • Condition assessment • Deflection (for flexible pipe) or joint (for rigid pipe) inspection 13.4 Performance Feedback State agencies are encouraged to consider tracking and evalu- ation of findings from implementation of the Recommended Practice and other aspects of highway drainage design, con- struction, and maintenance to allow for continual improve- ment and refinement of agency policies. Additionally, sharing performance feedback through national surveys, AASHTO and TRB committees, and other mechanisms helps advance the state of knowledge and practice.