Visual Characteristics of Drivers at Different Sections of an Urban Underpass Tunnel Entrance: An Experimental Study

The increase in the number of traffic accidents due to increasing urban underpass tunnels necessitate a better investigation drivers’ visual characteristics when entering tunnels. A total 20 drivers were gathered perform real vehicle experiment an tunnel. saccade angle, frequency, and fixation time selected as research indexes. tunnel entrance was divided into five sections, namely external straight line section, upper half ramp, lower shading shed inner section. results showed that angle frequency ramp significantly smaller than interior, range front more concentrated. changes difference 15th-85th threshold each section analyzed. all sections distributed within 149.476 475.414 ms. driver’s concentrated sidewalls higher closer portal.