Page 84 - Bridge and Highway Structure Rehabilitation and Repair
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CHAPTER 2                         DIAGNOSTIC DESIGN AND SELECTIVE RECONSTRUCTION             59



        3. Superstructure rehabilitation issues (as discussed in Chapter 1):
            •   Deck reconstruction and design
            •   Deck protective system
            •   Steel superstructure rehabilitation
            •   Deck joints: Joint types, compression seals, strip seals, modular and expansion joints,
              joint replacement, deck joint rehab, joint design
            •   Deck drainage: Scuppers, inlets
            •   Bridge railings: Bridge railing rehab
            •   Barrier design: Median barrier and parapets
            •  Bearings retrofit and design: Evaluation and strengthening of rocker and roller types,

              elastomeric pads, sliding, multi-rotational, dampers, and seismic isolation bearings

            •  Girder retrofit: Composite sections, shear connectors, web stiffeners, cross frame design,
              design of splice

            •  Bearings retrofit and replacement: Restrainers, seat width improvement
            •   Special procedures for through bridges
            •   Utilities relocation: Design of hangers and pipe supports.
        4. Substructure rehabilitation issues:
            •   Geotechnical issues and foundation design: Foundation types, underpinning and rehabili-
              tation, mini piles, pin piles, pile groups, caissons
            •   MSE walls, modular walls, restoring abutments and piers, underpinning methods
            •   Abutment and wingwall repairs
            •  Pier jacketing
            •  Column strengthening
            •  Seismic retrofi t
            •   Scour countermeasures retrofi t.

        2.3.8 Geometric Issues

            Both AASHTO Standard 16th Edition and AASHTO LRFD specifications address the fol-

        lowing standard issues for bridges to remain functional:
        1. Design speed.
        2. Lane and shoulder width.
        3. Maximum profi le grade.
        4. Minimum horizontal radius.
        5. Super-elevation rate and cross slope.
        6. Stopping sight distance and K value.
        7. Clearances—vehicular/navigational.
        8. Level of service.
            Design exceptions as required need to be approved by the state.

        2.3.9  Parameters Affecting Functional Obsoleteness
            The following parameters causing functional obsoleteness need attention:
        1. The deck geometry.
        2. Load carrying capacity.
        3. Clearances.
        4. Approach roadway alignment.
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