Page 48 - Bridge and Highway Structure Rehabilitation and Repair

CHAPTER 1 OVERVIEW OF BRIDGE ENGINEERING 23

Experience has shown that many of the construction documents may be lost over time.
Databases of scanned copies should be maintained as electronic fi les.
3. Checklist
A checklist of bridge inventory items for structural evaluation should include:
• Deck repairs or replacement
• Deck joint repairs or replacement
• Parapet or railing repairs or replacement
• Repainting of girders.

4. Records of emergency repair methods, including accidents, fire, extreme events, etc.
5. Maintenance schedule.

1.8 A LOOK AHEAD FOR PROGRESS IN MAINTENANCE
1.8.1 Upgrading Knowledge Database/Theoretical Approach

1. Progress in the structural mechanics and applied mathematics areas has not been signifi cant
in the past 50 years. Development of closed form solutions is desirable to:
• Identify and maintain consistent reliability indices within LRFD for all bridge and highway
structure elements, including calibration to reflect local materials and practices.

• Identify and calibrate the service limit states.
• Integrate information from maintenance and operations into code development and vice
versa.
• Identify load distribution for foundation elements.
2. For simple spans, design formulae for moving live loads are developed by the author in
Chapter 4. Similarly, rating formulae are provided in Chapter 6. Additional concepts are
provided through design techniques covered in Section 2.
3. Load and resistance factor rating (LRFR) methodology has been adopted by different states.
There is always a need to improve the durability of transportation structures within the
context of the LRFD specifi cations.

1.8.2 Accessing Databases of Bridge Failures
Applying failure theories and introducing preventive methods: The life of structures can be
increased by studying the reasons for failures and developing a methodology to minimize them.
Details are provided in Chapter 3 of this book.
1.8.3 Improved Seismic Resistant Design and Erosion Science

Methods to monitor foundations against extreme events to protect and/or strengthen founda-
tions against scour, earthquake, and impact damage are required.
The objectives are to strengthen the soil, liquefaction mitigation, and to protect foundations

against saltwater and corrosion. Retrofit techniques for improved foundation performance under
extreme events need to be developed.
Details for scour and seismic retrofits are provided in Chapter 12 of this book.

1.8.4 Optimizing Structural Systems by Use of Enhanced Concrete and New Materials
1. Deck overlays, high-performance concrete, high-performance and corrosion-resistant steels,

and fiber reinforced polymer composites have demonstrated significant initial and long-term
cost savings, and more efficient construction, resulting in less traffic disruption. Geo-ma-

terials, geo-synthetic products, and ground improvement techniques can be utilized. Some
of the newer materials like self consolidating concrete and ultra high performance concrete
for superstructures can increase effi ciency.