Crash analysis of foam and concrete filled automatic retractable bollard under vehicle impact

Author(s):  
M.D. Goel
2016 ◽  
Vol 2016 ◽  
pp. 1-17 ◽  
Author(s):  
Tae-Hoon Lee ◽  
Gun-Ha Yoon ◽  
Seung-Bok Choi

This paper investigates the deploying time (or response time) of an active hood lift system (AHLS) of a passenger vehicle activated by gunpowder actuator. In this work, this is accomplished by changing principal design parameters of the latch part mechanism of the hood system. After briefly introducing the working principle of the AHLS operated by the gunpowder actuator, the governing equations of the AHLS are formulated for each different deploying motion. Subsequently, using the governing equations, the response time for deploying the hold lift system is determined by changing several geometric distances such as the distance from the rotational center of the pop-up guide to the point of the latch in the axial and vertical directions. Then, a comparison is made of the total response time to completely deploy the hood lift system with the existing conventional AHLS and proposed AHLS. In addition, the workable driving speed of the proposed AHLS is compared with the conventional one by changing the powder volume of the actuator.


Author(s):  
Jorge Ambrósio ◽  
Marta Carvalho ◽  
João Milho ◽  
Susana Escalante ◽  
Roberto Martín

Author(s):  
Yongjun Pan ◽  
Yue Xiong ◽  
Wei Dai ◽  
Keshan Diao ◽  
Lei Wu ◽  
...  

Author(s):  
Darren J. Torbic ◽  
Jessica M. Hutton ◽  
Courtney D. Bokenkroger ◽  
Marcus A. Brewer

This paper presents the results of a study to develop improved design guidance for freeway main-line ramp terminals on the basis of modern driver behavior and vehicle performance capabilities. The primary steps included a crash analysis, an observational field study, and a driver behavioral study. This research reached several key conclusions, as follows. Vehicle merging speeds tend to be closer to freeway speeds at tapered acceleration lanes than at parallel acceleration lanes. The recommended minimum lengths for acceleration lanes presented in the 2004 edition of AASHTO's A Policy on Geometric Design of Highways and Streets (Green Book) are conservative and, under certain conditions, could be reduced by 15%. In a situation in which a significant volume of trucks uses an entrance ramp, an acceleration lane length that will better accommodate trucks can be derived by using speed–distance curves developed for a range of weight-to-power ratios. The recommended minimum lengths for deceleration lanes presented in the 2004 Green Book are conservative and do not account for deceleration in the freeway. Providing deceleration lanes longer than the minimum values given in the Green Book may promote casual deceleration by exiting drivers. Several potential changes for consideration in the next edition of the Green Book are recommended on the basis of the findings and conclusions of this research.


2013 ◽  
Vol 52 ◽  
pp. 240-256 ◽  
Author(s):  
Qian Wang ◽  
Hongbing Fang ◽  
Ning Li ◽  
David C. Weggel ◽  
Guilin Wen
Keyword(s):  
Fe Model ◽  

2005 ◽  
Author(s):  
Zenovy S. Wowczuk ◽  
Gerald M. Angle ◽  
Emily D. Pertl ◽  
James E. Smith

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