Page 65 - Bridge and Highway Structure Rehabilitation and Repair

40 SECTION 1 ADMINISTRATIVE ISSUES

routes. Hence, all important and weight restricted bridges need increased inspections.
Maintaining a healthy interstate and local transportation system requires diagnosis based

on regular inspections by a team of qualified inspectors and repairing the bridge to an
acceptable standard.

2.1.2 An Engineering Approach to Rehabilitation
1. Many activities accompany rehabilitation. In addition to recommending optimal rehabilitation
procedures and developing solutions to the long term needs of the crossings and the manner
in which to address them, public perception is important. What may be most important to

the public are traffic delays caused by disruptions for recurring repairs.
When the public is involved early in a project, their suggestions can make planning
easier. If they fully understand the reasons for proposed delays due to staged construction
or detours, they are more likely to accept delays when they occur. Often times, the public
helps to shape and form the way work is performed. A thorough public outreach program
is therefore paramount to a successful project.
2. A bridge widening feasibility study to address future improvements may also be carried
out. Approval of reports by the owner is followed by preparing preliminary and fi nal design
plans and providing post design services for the initial near-term repairs.
A team effort is required to prepare a concept study for the near-term repairs in a report
documented with plans, including a condition assessment of the bridge and approach road-
ways.
3. The objectives are to restore serviceability and original functionality following distress

from severe localized deterioration, flood or vehicle impact damage, wind, earthquake, and
observed scour. Rehabilitation/repair tools such as preventive maintenance actions, life
cycle costs evaluation, and bridge management systems will be applied for near-term and
long-term tasks. Practical considerations may be summarized as follows:
• For increasing the width of the bridge in the long term, the deck slab in a through girder

bridge is made wider and the supporting floor beams longer.
• For bridges located on waterways, underwater inspections are needed to evaluate the current
conditions of foundations based on which existing abutments and piers will be restored.
• Environmental impact should be minimized, and river pollution should be prevented dur-
ing construction.
• The historic appearance and shape of members should be maintained.

• Traffic detours should be kept to a minimum.
• Most near-term repairs should be salvaged for reuse in the long term.
• Safety of the bridge through increased redundancy and carrying out structural analysis
for the new system with cables for live loads and speed should be ensured.
• Public needs regarding bridge closures and construction schedules should be addressed
through outreach.
• Near-term repairs include those that can be accomplished with minimal impact to
traffi c
• Coordination with utilities and roadway agencies to identify acceptable reconstruction
solutions is required.

2.1.3 Engineering Maintenance
1. Engineering maintenance is another name for need-based mitigation and reconstruction (Fig-
ure 2.1). It is a combination of both art and science for protecting, strengthening, upgrading