为提高低等级混凝土护栏防护重型车辆的能力，设计了3种不同构造形式的复合材料护板，分别设置在混凝土护栏表面形成组合式护栏。建立车-护栏精细化有限元模型，通过与实车碰撞试验结果对比，验证了有限元模型的可靠性。考虑撞击力、碰撞角度、车辆轨迹、货厢尾部抬高、车辆动态外倾值、车辆外倾角6个评价指标，对比分析了3种方案护栏的防车撞性能。结果表明，在整体式货车撞击下，3种方案护栏均能顺利引导车辆转向，不带阻坎的方案一的各主要指标均优于其他方案，防护能力最优；在拖挂式货车撞击下，方案一的护栏导向与阻挡性能依然良好，驶出角仅为0.75°；改造后的组合式护栏防护能量达到650 kJ，防护能力是改造前的4倍。

To improve the protective capabilities of existing low-grade concrete guardrails against heavy vehicles,three types of composite protective plates designed for direct installation on the surface of concrete guardrails were developed. Refined finite element (FE) models of truck-guardrails were established, and the reliability of these models was verified by comparison with crash test results. Six evaluation indexes, including impact force,collision angle variations,vehicle trajectory, height variations of the carriage box tail,vehicle dynamic extroversion value and camber angle, were considered. The anti-collision performance of the three schemes was compared and analyzed. The results indicate that all three kinds of guardrails effectively guide vehicles to turn smoothly during the integral truck impacts. Scheme 1, without hindrance, demonstrates superior performance in key indices compared to the others. Under towed truck impacts, scheme 1 exhibits excellent guiding and blocking capabilities, with an exit angle of only 0.75°.The protection energy of the combined guardrail reaches 650 kJ,providing a protection capacity 4 times greater than the existing low-grade guardrail.

U417.1+2

重庆市自然科学基金资助项目（CSTB2022NSCQ-MSX1658）；贵州省科技计划资助项目（黔科合支撑（2022）026）。