civl 7

  1. Long spans-difficult engineering challenge due to
    • Available construction technology and structural materials
    • Forces of nature such as gravity, earthquakes, and strong winds
    • Harsh working environment
  2. Slab Bridges
    • Easy to construct
    • short spans
    • High self-weight
    • Material: Reinforced or prestressedconcrete
  3. Voided Slab Bridges
    • Voids introduced to reduce self weight
    • May adopt solid section near supports (larger shear)
  4. Beam-and-Slab Bridges
    • Beams uniformly spaced across the bridge’s width
    • Columns at each pier
  5. Box Girder Bridges
    • Hollow box shape (rectangle / trapezoid / triangles)
    • Strong in torsion
    • freeway overpasses
  6. truss bridges
    • rigid joints at openings, stronger than the triangles
    • only tension and compression develops
    • force develop along the members
    • wires cannot take compression
    • statue of liberty
  7. arch bridge –type
    deck, through, half-through
  8. arch bridge –eg
    • ChaotianmenBridge - longest arch bridge (main span: 552 m)
    • Sydney Harbor Bridge- Tallest steel arch bridge
  9. Suspension Bridges-eg
    • Golden Gate Bridge
    • Tsing Ma Bridge- longest suspension bridge
    • Bitan Suspension Bridge
  10. Suspension Bridges
    • Cable, suspenders and anchorages under tension
    • Towers under compression
  11. Cable-stayed Bridge-type
    • Fan cable stays and harp cable stays
    • A-frame, H-frame
  12. Cofferdams is…..made of ….;building procedures; it can be easily damaged due to…
    • Temporary enclosure standing in water to create a dry environment to proceed with work;
    • Sheet pile
    • Must be built before Building the bridge & when water is shallow, start with building the frame, then drive the sheeting around the parameter by using a vibratory hammer, then pump out the water and drive the foundation piles;
    • Pump out the water
    • Overflooding (not much higher than water level) AND
    • Strong currents and soil mud shifting out can bend the cofferdam
Card Set
civl 7
civl 7