摘要
针对现有《公路安全设施设计细则》的传统护栏缺失对高速公路弯道护栏的设计细则问题,对车—护栏系统在急弯路段、高速、大角度发生碰撞的防护性能进行了研究,采用有限元仿真的方法(基于Pro-E建模、Hyper-Mesh前处理、LS-DYNA仿真),模拟小车以速度分别为80 km/h、100 km/h,碰撞角度为25°碰撞A级传统波形梁护栏,提出了从车辆行驶轨迹、车辆质心加速度、系统能量以及车辆损伤形态4个方面来系统研究护栏在碰撞中的阻挡、缓冲及导向作用,并设计了一种新型柔性缓冲防护栏结构。仿真结果表明:A级传统波形护栏与立柱的夹角小于60°,且最大瞬时减速度大于20g,不能满足法规规定的碰撞防护要求;而新型柔性缓冲护栏能利用防撞圈来缓冲碰撞过程,并且其最大的变形仅为传统护栏的14%,动能转化为内能的比率下降40%,能引导车辆以一定车速回到原车道,防止二次事故。
Aiming at the existing ＂Guidelines for Design of Highway Safety Facilities＂ which is lack of risk analysis for highway guardrail in the corner, protection performance of the ear-guardrail system were studied in sharp sections, high speed, large angle of collision. The collision processes in collision angle equal 25 degree and with the velocity of car at 80 km/h or 100 km/b respectively were simulated by the means of finite element method （built model by Pro-E, preproeessed by Hyper-Mesh, simulated by LS-DYNA）. 4 indicators, vehicle＇s tractory, acceleration, enery and damage, were putted forward to assess the effect of guardrail, meanwhile a new type of barrier with flexible buffer device was designed. The results indicate that the A level of w-beam guardrail can＇t meet the collision protection needs which that the intersection angle of it with column is less than 60 degree and maximum instantaneous deceleration of vehicle exceeds 20g in simulation. It indicate that the new device could utilize steel rope absorbers to buffer the collision processes. Compared with the traditional fence, maximum deformation of vehicle is only its 14% and the ratio of kinetic energy into internal energy fell by 40% yet. And it guides it return to its normal lane that prevents the following secondary accidents.
出处
《机电工程》
CAS
2015年第12期1549-1554,共6页
Journal of Mechanical & Electrical Engineering
基金
国家自然科学基金资助项目(11372148)
关键词
车辆碰撞
弯道
高速护栏
柔性装置
vehicle collision
bend
highway guardrail
flexible device
