Page 90 - Bridge and Highway Structure Rehabilitation and Repair

CHAPTER 2 DIAGNOSTIC DESIGN AND SELECTIVE RECONSTRUCTION 65

• Obtaining and examining bridge inventory, load rating data, and the latest inspection report
considering the overall condition of the bridge and the specific condition of the major

structural elements
• The year constructed and design loading provides clues to the potential serviceability of
a rehabilitated structure
• Identifying geometry, materials used, and details that may limit potential alternatives
• Obtaining and examining record plans, structure width, type of construction, materials
used, and fabrication methods employed.
2. Verifying documented Information includes the following steps:
• Verifying data to assure that the information in the bridge inventory and inspection system
and on the record plans is accurate
• Visiting the project site. This is not meant to be an in-depth bridge inspection, rather, a

verification visit to assist in a feasibility assessment.
3. Evaluating the hydraulic adequacy of the structure, if applicable, includes the following
steps:

• Identifying susceptibility to flooding, scour, and damage from floating ice and debris

• Performing a hydraulic assessment
• Performing some preliminary engineering activities prior to the closure of scoping
activities
• The technical activities for this phase are focused on the feasibility, including a list of
reasonable alternates and their cost estimates.

• General considerations that help define the feasibility of each alternate are required.
4. Determining reasonable costs and a schedule for the most feasible alternate includes the
following steps:
• Providing project specific programming information

• Comparing general requirements of work to other projects of similar size and type and
estimating a reasonable cost for work
• Preparing an approximate schedule.
5. Summarizing recommendations of scoping activities includes the following steps:
• The information gathered and the conclusions reached through these activities should be
presented in the project’s scoping document.
• Any unfeasible alternates should be eliminated.
6. Projects requiring painting: Repainting of steel bridges is required at regular intervals of 15
to 20 years, especially for structures located over rivers. To remove and dispose of existing
lead-based paints, repainting costs have escalated in recent years and in some cases have
become nearly comparable to the cost of a new bridge. The steps are:
• The cost effectiveness of fresh paint, which may only last 20 years, needs to be investigated.
When combined with rehabilitation costs, the total expenditure may justify its replacement,
especially for functional improvements such as providing additional lanes, sidewalks, or
increased live load capacity.
• Any paint containing lead or toxic materials must be indicated, either on the plans or in a
special provision, to advise the contractor for taking necessary precautions.
• If lead or toxic material content in the paint system is not known, samples need to be
sent for analysis. Information on the prospective bidder’s test results will be included in
bidding documents, whether or not lead is present in the paint.