CES 3 - Module 1

• Bridge


  a structure built over a river, railroad, highway, etc. to provide a way across for vehicles or pedestrians
• Bridge Engineering


  is an engineering discipline branching from 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 (Yaghoubi, 2018)
• If the width of a bridge is insufficient to carry the number of lanes required to handle the traffic volume, the bridge will be a constriction to the traffic flow
• If the strength of a bridge is deficient and unable to carry heavy trucks, load limits will be posted, and truck traffic will be rerouted. The bridge controls both the volume and weight of the traffic carried
• Bridges are expensive. The typical cost per mile of a bridge is many times that of the approach roadways. This is a major investment and must be carefully planned for best use of the limited funds available for a transportation system
• Stone Arch Bridges


  The Roman bridge builders first

  come to mind when discussing stone arch bridges. They utilized the semicircular arch

  and built elegant and handsome aqueducts and bridges, many of which are still standing today.
• Wooden Bridges


  Early bridge builders began their careers as millwrights or carpenter- mechanics.
• Metal Truss Bridges


  along came the railroads with their heavy loads, and the wooden bridges could not provide the necessary strength and stiffness for longer spans. As a result, wrought iron rods replaced wooden tension members, and a hybrid truss composed of a combination of wood and metal members was developed.
• Suspension Bridges


  carries vertical loads through curved cables in tension. These loads are transferred both to the towers, which carry them by vertical compression to the ground, and to the anchorages, which must resist the inward and sometimes vertical pull of the cables.
• Metal Arch Bridges


  also known as a through-type arch bridge, is a bridge that is made from steel, in which the base of an arch structure is below the deck but the top rises above it.
• Reinforced Concrete Bridges


  In contrast to wood and metal, reinforced concrete has a relatively short history. It was in 1824 that Joseph Aspdin of England was recognized for producing Portland cement by heating ground limestone and clay in a kiln
• Girder Bridge


  Some of the early girder bridges, with their multiple short spans and deep girders, were not very attractive. However, with the advent of prestressed concrete and the development of segmental construction, the spans of girder bridges have become longer and the girders more slender
• Highway Design for the overpass and underpass alignment and geometry.
• Structural Design for the superstructure and substructure elements.
• Geotechnical Engineering for the pier and abutment foundations.
• Hydrology and Hydraulics for proper bridge span length and drainage of bridge site.
• Surveying and Mapping for the layout and grading of a proposed site
• Span


  a segment of bridge from support to support
• Superstructure


  comprises all the components of a bridge above the supports
• Wearing Surface


  portion of the deck cross section that resists traffic wear. Could be: Separate layer made of bituminous material, else, integral part of concrete deck
• Deck


  the physical extension of the

  roadway across the obstruction to be bridged. It can be a reinforced concrete slab. In an orthotropic deck bridge, the deck is a stiffened steel plate.
• Stringers or girders


  Beam-type primary members
• Secondary Members


  are bracing between primary members designed to resist cross-sectional deformation of the superstructure frame and help distribute part of the vertical load between stringers
• Abutments


  are earth-retaining structures that

  support the superstructure at the beginning and end of a bridge
• Piers


  are structures that support the superstructure
• Bearings


  are mechanical systems that transmit the vertical and horizontal loads of the superstructure to the substructure and accommodate movements between the superstructure and the substructure
• Substructure


  consists of all elements required to support the superstructure
• Pedestal


  is a short column on an abutment or pier under a bearing that directly supports a superstructure primary member
• Stem


  is a primary component of the abutment above the footing, supporting pedestals. Its main function is to transfer loads from superstructure to the foundation
• Backwall


  is the component of the abutment acting as a retaining structure on top of the stem. It also supports an approach slab, if there is one.
• Wingwall


  is a side wall to the abutment backwall and stem designed to assist in confining earth behind the abutment. Wingwalls may be designed parallel to the bridge and approaches, or they may have a skew angle
• Footing


  transfer loads from the substructure to the subsoil or piles.
• Piles


  are used when the soil under a footing cannot provide adequate support for the substructure
• Sheeting


  is the vertical planks that are driven into the ground to act as temporary retaining walls permitting excavation in cofferdams or shallow excavation
• Appurtenances and Site- related Features


  is 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
• Slope protection


  cover for the slope: both aesthetically pleasing and provide proper drainage/erosion control
• Underdrain


  drainage of a major substructure element, such as an abutment
• Approach Roadway


  The section of overpass roadway that leads up to and away from the bridge abutments
• Approach Slab


  used to compensate for potential differential settlement at the approaches
• Bridge Barriers


  are provided to restrain vehicles from crashing off the side of a bridge