Discuss this Article. They dilated my daughter's eyes 18 hours ago, and they're still dilated. Anyone that says the eyes are back to normal in 6 hours does not know what they're talking about. The job of an eye doctor is not let their patients go blind. Retinal issues are the number one cause of blindness in north america, and most limiting factor of seeing the retina is the size of the pupil.
A truss bridge is a bridge composed of connected elements (typically straight) which may be stressed from tension, compression, or sometimes both in response to loads. Truss bridges are one of the oldest types of modern bridges. The basic types of truss bridges are shown below.
All of the stateâs other truss bridges are metal structures, which partook of an explosion of design and technological innovations that began in the mid-19th century. Basic truss bridge types found in North Carolina (source: HAER). A truss bridge can be characterized by the location of its traffic deck. At a pony truss, the travel surface passes along the bottom chords of trusses standing to either side that are not connected to each other at the top. These trusses are designed for lighter loads. At a through truss bridge, the deck again is carried along the bottom chord, but the trusses to either side are generally higher and are connected by cross-bracing at their tops. Designed for heavier loads and longer spans, this truss is the most common in North Carolina.