Design and Engineering of Urban Interchange Ramp Bridge Structure

This paper analyzes the structural design of an urban interchange ramp bridge from four aspects,which are the superstructure,pier structure,foundation structure,and deck structure design to summarize the structural design ideas of this urban interchange ramp bridge,which can be used as a reference for future construction of the same bridge.

Strategies for Ramp Route Design of Highway Interchange

The rapid advancement of urban transportation in modern China has driven urban economic developments.However,the progressively congested traffic conditions have affected the productivity and daily life of the people.To mitigate the congestion problem,necessary road designs should be implemented along the highways,for example highway interchanges.The application of highway interchanges in past cases have proven to effectively avoid traffic flow conflicts,reduce highway traffic congestion,and reduce traffic accidents,this is conducive to ensuring the safety and efficiency of the highway.In order to improve the safety and convenience of urban road traffic,this paper analyzes the strategy of using interchange ramp route designs for highway traffic.

Evaluation of navigation performances of GPS devices near interchange area pertaining to wrong-way driving

Based on past studies, exit ramp terminals are the common locations for drivers to enter a physically separated highway in the wrong direction. Currently, many drivers, especially nonlocal drivers, often rely on voice-guided navigation apps and Global Positioning System （GPS） devices to navigate their routes on and off freeways. A few studies have reported that GPS devices sometimes give drivers wrong information and cause wrong-way entry into a freeway, especially at some confusing interchanges, such as partial cloverleaf and compressed diamond interchanges. The access points located close to exit ramps may also cause a problem for GPS devices in sending accurate voice-guidance. It is unknown if current GPS devices are capable of properly informing drivers regarding turning movements in advance of exit ramp terminals at some common interchanges. The objective of this study is to evaluate the most commonly used GPS devices/navigation apps to identify existing problems and their potential for reducing wrong-way driving （WWD） incidents at interchange terminals. Field experiments were conducted at 10 common freeway interchanges or interchanges with nearby access driveways in the state of Alabama. Results show that most GPS devices have difficulty in providing correct guidance when the spacing between an access point and an exit ramp is less than 300 feet. Our comparison of five different GPS devices used on the same routes reveals that navigation apps have more limitations in guiding drivers than stand-alone GPS devices. Recommendations are offered to help GPS mapping companies improve their devices or add new features to reduce the occurrence of WWD.