摘要
结合高速公路拓宽改建工程案例,基于有限元计算技术,对既有高速公路沥青路面结构进行不同交通工况的力学响应分析,根据计算结果提出了上中面层实行材料性能差异的车道差异化路面结构设计方案;分析设计年限内临近轻载与重载车道之间形成的路面内部上中面层竖向界面及其下层竖直面上的剪应力,研究接触状态和荷载作用位置对剪应力的影响规律及剪切破坏的可能性。结果表明,荷载作用位置不同时,界面及下层竖直面上产生的剪应力分布规律也不同,荷载位于重载车道中央时剪应力随着深度增加在逐渐增大,最大值出现在半刚性材料底基层层底;而位于竖向界面顶部时,剪应力随路面深度的增加逐渐减小,最大值出现在路表,且可产生导致剪切破坏的较大剪应力;竖向界面需设置在轻重载车道之间的划线处,可确保该处实际不会产生剪切破坏;轮迹带处产生剪切破坏几乎成为必然,因此,采取工程措施加强面层强度并进行剪切强度验算是必要的。
Combined with the case of expressway widening and reconstruction project,based on the finite element calculation technology,the mechanical response analysis of the existing asphalt pavement structure of expressway under different traffic conditions was carried out.According to the calculation results,the differential pavement structure design scheme with different material properties on the upper and middle surface layers was proposed.The shear stress of the vertical interface in the upper and middle surface layer and the vertical surface of the lower layer formed between the adjacent light-load and heavy-load lanes within the design period were analyzed.And the influence law of the contact state and the position of load on the shear stress and the possibility of shear failure were studied.The results show that the shear stress distribution law of interface and lower vertical surface is different when the load position is different.When the load is located in the center of the heavy-load roadway,the shear stress increases gradually with the increase of pavement depth,and the maximum value appears at the bottom of the semi-rigid material base layer.However,at the top of the vertical interface,the shear stress gradually decreases with the increase of pavement depth,and the maximum value appears on the pavement surface,which can produce a large shear stress leading to shear failure.The vertical interface should be set at the underlined point between the light and heavy traffic lanes to ensure that there is no actual shear failure.Because the shear failure at the wheel track is almost inevitable,it is necessary to take engineering measures to strengthen the surface strength and to check the shear strength.
作者
刘兆新
杨广亮
赵启睿
孙振浩
马峥浩
刘树堂
LIU Zhao-xin;YANG Guang-liang;ZHAO Qi-rui;SUN Zhen-hao;MA Zheng-hao;LIU Shu-tang(Shandong Hi-speed Group Co., Ltd., Jinan 250000, China;School of Qilu Transportation, Shandong University, Jinan 250002, China)
出处
《科学技术与工程》
北大核心
2022年第1期367-373,共7页
Science Technology and Engineering
基金
山东省自然科学基金(ZR2019BEE004)。
关键词
沥青路面结构
车道差异化设计
轻重载车道
数值计算
剪应力
asphalt pavement structure
lane differentiation design
light and heavy loading lanes
numerical calculation
shear stress
