新型再生发泡混凝土墙式护栏防车撞试验与模拟  

Experimental and Numerical Investigation of the Anti-collision Performance of a Novel Recycled Foamed Concrete Guardrail

作　　者：张新晨 方海[1] 张喆 姜维 祝露[1] 张清玲 高涵 ZHANG Xin-chen;FANG Hai;ZHANG Zhe;JIANG Wei;ZHU Lu;ZHANG Qing-ling;GAO Han(School of Civil Engineering,Nanjing Tech University,Nanjing 211816,Jiangsu,China;China Construction Institute of Advanced Technology,Wuhan 430075,Hubei,China)

机构地区：[1]南京工业大学土木工程学院,江苏南京211816 [2]中建三局集团有限公司,湖北武汉430075

出　　处：《中国公路学报》2024年第5期122-137,共16页China Journal of Highway and Transport

基　　金：国家重点研发计划项目(2022YFC3803400);国家自然科学基金项目(52078248)。

摘　　要：设置防撞护栏是保障高等级公路交通安全的基本途径之一,在中国具有广泛的应用。然而,传统护栏的刚性偏大,耗能能力相对较弱,车撞下可能导致较严重的车辆损毁和人员伤亡。基于此,提出了一种将再生发泡混凝土作为缓冲材料的新型SS级墙式护栏,该护栏采用了一定量的砖混建筑固废作为原料,具备较好的经济性和绿色低碳属性,同时将其与薄壁钢外壳组合,形成一种外挂便于更换的耗能导向部件,提高整体护栏的可恢复性。针对该新型护栏的吸能特性与防护效果,开展了足尺车辆撞击试验和数值模拟研究。试验结果表明:该新型护栏具有较好的缓冲吸能特性,发生撞击后,车辆保持了较好的完整性,钢外壳导向痕迹明显,发泡混凝土充分吸能,脱落率达20%以上。相较于传统普通护栏,撞击力峰值削减幅度超过54%、平行和垂直护栏方向加速度峰值削减分别达到55%和61%以上。研究进一步建立了车、护栏精细化有限元分析模型并开展了模拟撞击分析,通过和试验结果对比验证了其准确性。根据规范对于新型护栏在实际使用时的阻挡、导向等功能要求,开展了新型护栏与小型客车、大型客车和大型货车3种车辆的撞击模拟,结果表明,新型护栏的再生发泡混凝土缓冲层溃缩吸能可以有效减轻护栏固定层和碰撞车辆的损伤,其吸能占比随着冲击能量等级的增加而增加,最高达到了35%左右。所有工况下,撞击车辆均未发生穿越、翻越、骑跨的现象,验证了新型护栏在实际使用过程中较好的阻挡、导向功能,具有较好的应用前景。A guardrail is one of the basic means of ensuring the safety of high-grade highway traffic,and it is widely used in China.However,traditional guardrails have a high rigidity and relatively weak energy absorption capacity,which can lead to severe vehicle damage and casualties in the event of a collision.In this context,this study proposes a novel SS-grade wall-type guardrail that utilizes recycled foam concrete as a cushioning material.A certain amount of brick and concrete construction waste is used as the raw material,which offers economic advantages and green low-carbon properties.Additionally,foam concrete is combined with a thin-walled steel shell,forming an externally attached energy-absorbing component that is easy to replace,which enhances the overall recoverability of the guardrail.To evaluate the energy absorption characteristics and protective performance of this novel guardrail,full-scale vehicle impact tests and numerical simulations were conducted.The test results demonstrate that the novel guardrail exhibits favorable cushioning and energy absorption properties.After an impact,the vehicle maintains a good level of integrity;meanwhile,the steel shell shows clear guiding traces,and the foam concrete effectively absorbs energy,with a detachment rate exceeding 2o%.The peak impact force reduction exceeds 54%,and the peak acceleration reduction in both the parallel and vertical guardrail directions exceeds 55%and 61%,respectively,compared to those of the traditional standard guardrail.Furthermore,a refined finite element analysis model of the vehicle and guardrail is established,and simulated impact analyses are conducted.The accuracy of the model is verified by comparing its results with the experimental results.Based on the functional requirements of the novel guardrail in terms of obstruction and guidance according to specifications,simulations of the guardrail's impact with three types of vehicles-small cars,large buses,and heavy trucks-are conducted.The results indicate that the foam concrete cushion

关 键 词：桥梁工程 墙式护栏 冲击试验 再生发泡混凝土 撞击力 车辆安全 

分 类 号：U417.12[交通运输工程—道路与铁道工程]