• Journal of Korea Water Resources Association
• /
• v.47 no.12
• /
• pp.1165-1176
• /
• 2014

In a river bend the water surface is inclined by the centrifugal force toward the transverse section. If channel slope and flow rate increase, the gradient is rising generally. There are lots of the flood damage at the bends of mountain river because the flood water levels have exceeded frequently the levee levels which are added a free board to the design flood water level. Therefore the superelevation should be considered in designing the mountainous river bend. In present study it was proposed to estimate the superelevation at the bend of mountain river and the superelevation coefficient defined from multiplying the sub-factors. The values of the influence factors for the superelevation coefficient were suggested from analyzing the superelevation measured at the bends in Yangyangnamdae river and the hydraulic experiments in gravel-bed channel with a $90^{\circ}$ bend. The applicability of these methods to estimate the superelevation at the bends in mountain river was verified by the superelevation measured at the bend in Naerin river.

• 한국도로학회:학술대회논문집
• /
• 2006.10a
• /
• pp.275-282
• /
• 2006

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.13 no.2
• /
• pp.25-32
• /
• 2013

Entry speed of the vehicle and lateral acceleration acting on the vehicle, roll-angle associated with the overthrow, and then the structure of the road, the friction of road surface are important factors in turning on the curved road. In this study, we analyzed the state change of the vehicle causing entry speed of the vehicle and superelevation of the road, the friction coefficient by using a PC-crash Program for traffic accident reconstruction. As a result, when vehicle is turning the curved road, we could ascertain that the structure of the road and state of the road surface are a major factor about the set up of limited speed.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.11 no.6
• /
• pp.111-122
• /
• 2012

There has been a strong demand for providing diverse services to drivers utilizing existing ITS infrastructure. To this end, this study is aiming at improving the accuracy of a variable speed limit system by determining recommended speeds for the system utilizing the information from Urban Traffic Information System(UTIS) and Weather Information System(WIS). In order to determine appropriate speed limits under inclement weather conditions for the variable speed limit system, this study examined three methods: i) the method utilizing the information from WIS, ii) the method utilizing the information from UTIS, and iii) the method which combines the information from WIS and UTIS using different weights for diverse weather conditions. Finally, this study selected the third method which determines an appropriate speed limit using the relationship between the vehicle operating speed and the minimum stopping distance which is estimated using the existing speed limit, surface coefficient of friction and superelevation.