Bridge Engineering Basics

Study Notes

Bridge engineering is a branch of civil engineering that involves the planning, design, construction, operation, maintenance, and rehabilitation of bridges to ensure safe and effective transportation of vehicles, people, and goods.
A bridge is a key element in a transportation system, and balance must be achieved between handling future traffic volume and loads and the cost of a heavier and wider bridge structure.
Strength and measures to prevent deterioration are crucial considerations in bridge engineering.

Bridge engineering is important because a bridge's failure can cause system failure, and it has the highest cost per mile.
The designer of new bridges must make wise decisions to balance capacity and cost, and ensure safety is not compromised.

The modern highway bridge originated from the Industrial Revolution, which began in the last half of the eighteenth century and saw the emergence of cast iron, wrought iron, and finally steel for bridges.
The use of reinforced concrete in bridges began in 1824 with Joseph Aspdin's production of Portland cement.
Prestressing construction techniques were first developed by the French engineer Ernest Freyssinet in the 1920s.

The development of bridges began with the stone arch by the Roman engineers of the second and first centuries BC.
The Renaissance period saw the building of beautiful bridges across Europe during the fourteenth through seventeenth centuries.

Appurtenances and Site-Related Features: any part of the bridge or bridge site that is not a major structural component yet serves some purpose in the overall functionality of the structure (e.g., guardrail).
Major Appurtenances and Site-Related Features: include slope protection, which provides for proper drainage and erosion control, and underdrain, which is a drainage system that transports runoff away from the structure.

Slab-on-girder: a bridge superstructure consisting of a concrete slab resting on a set of girders, which are connected by diaphragms to form a frame.
Advantages of slab-on-girder: simple design, uniform design that can be standardized easily, and economical repair methods.
Disadvantage of slab-on-girder: suitable for short-to-medium span lengths (up to 300 ft [91 m] for steel girders and 160 ft [49 m] for prestressed concrete girders).

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