Concrete Segmental Bridges

Theory, Design, and Construction to AASHTO LRFD Specifications

Dongzhou Huang, Bo Hu

• Publisher: CRC Press
• Year: 2020
• ISBN:
  9780429938832
• Edition: 1
• Topic: Technology & Engineering
• Subtopic: Construction & Architectural Engineering
• Index: Technology & Engineering

Segmental concrete bridges have become one of the main options for major transportation projects world-wide. They offer expedited construction with minimal traffic disruption, lower life cycle costs, appealing aesthetics and adaptability to a curved roadway alignment. The literature is focused on construction, so this fills the need for a design-oriented book for less experienced bridge engineers and for senior university students.

It presents comprehensive theory, design and key construction methods, with a simple design example based on the AASHTO LRFD Design Specifications for each of the main bridge types. It outlines design techniques and relationships between analytical methods, specifications, theory, design, construction and practice. It combines mathematics and engineering mechanics with the authors' design and teaching experience.

1Introduction to Concrete Segmental Bridges

• Development of concrete segmental bridges
• Construction materials and their properties
• Types of concrete segmental bridges and typical construction procedures
• AASHTO stress limits
• Post-tensioning systems
• General design procedures
• Aesthetics

1.1BRIEF HISTORY AND DEVELOPMENT OF CONCRETE SEGMENTAL BRIDGES

Concrete bridges that are built segment by segment or piece by piece are often called concrete segmental bridges. The basic principles of segmental construction have been in existence for thousands of years and were used by engineers to build arch structures. The Zhao-Zhou Bridge (see Fig. 1-1) built in 615 A.D. in China is the first shallow segmental stone arch bridge in the world. The individual wedge-shaped stones are pushed together by the self-weight of the stones, creating horizontal and vertical reactions at the ends of the arched supports. The reactions are essentially post-tensioning forces applied to the wedged-shaped stones. However, modern segmental bridges are comprised of concrete segments that are connected via post-tensioning forces applied by high-strength steel wires, bars, and/or strands. The first generation of prestressed concrete segmental bridges was constructed in the 1950s as part of the overall reconstruction and expansion of the European post–World War II infrastructure, particularly in Germany and France. As many manufacturing facilities had been damaged during the war, the need for reconstruction created a demand for large highway and railway bridges that could be constructed with minimal factory-manufactured items, such as steel members. The concepts and theory of prestressed concrete segmental bridges were forcibly advanced under these stringent conditions. In 1975, the PCI Committee on Segmental Construction officially defined the segmental construction as a method of construction in which primary load carrying members are composed of individual segments post-tensioned together^[1-1].

FIGURE 1-1Zhao-Zhou Bridge^[1-2], completed in 615 A.D., China (Courtesy of Prof. Bao-Chun Chen).

The first precast concrete segmental bridge was the Luzancy Bridge^[1-3] (see Fig. 1-2) over the Marne River in Paris. This bridge was designed by Eugène Freyssinet and was the first bridge application of post-tensioning using high-strength steel. The bridge construction was completed in 1948. The early contributions of Eugène Freyssinet and other pioneers' have led to the development of segment bridge theory and construction practices as we know them today.

FIGURE 1-2Luzancy Bridge, designed by Eugène Freyssinet, 1948.

The Balduinstein Bridge (see Fig. 1-3) built in 195...