Refer to Design Step 1 for introductory information about this design example. Additional information is presented about the design assumptions, methodology, and criteria for the entire bridge, including the steel girder. Figure 3-1 Span Configuration. Figure 3-2 Superstructure Cross Section.
HYPOFLUORESCENCE Hypofluorescence may be caused by 1) blocked fluorescence, which is synonymous with negative fluorescence or transmission decrease, or 2) a vascular filling defect. Blocked fluorescence corresponds to the size, shape, and location of the blocking material seen ophthalmoscopically.
The cause of fading is due to a photochemical reaction involving UV and visible light. Research has shown (above) that 40% of fading is caused by UV rays. Another 25% of fading is due to heat, with 25% being caused by normal visible light.The remaining 10% cause of fading is from indoor artificial lighting, humidity, and poor dye anchorage. Visible light and UV radiation cause fading and a lack of moisture, especially in the cloth materials used to cover books.Electromagnetic energy is measured in nanometers (nm.) UV is present from 100-400nm, and visible light is present from 400-700nm.The energy that exists from 100-700nm is thererfore responsible for 65% of all fading.lectromagnetic energy is measured in nanometers (nm.) UV is present from 100-400nm, and visible light is present from 400-700nm. The energy that exists from 100-700nm is thererfore responsible for 65% of all fading.