桥面沥青铺装设计新方法  

A new method for bridge asphalt pavement design

作　　者：赵锋军[1] 易伟建[1] 李宇峙[2] 

机构地区：[1]湖南大学,湖南长沙410082 [2]长沙理工大学,湖南长沙410076

出　　处：《土木工程学报》2006年第10期74-79,86,共7页China Civil Engineering Journal

摘　　要：提出一种不同于传统经验设计法的桥面沥青铺装理论设计方法。利用有限元方法计算分析桥面沥青铺装受力特性,发现“肋间距”与桥面板厚度是影响沥青铺装受力的关键因素,基于此结论,新设计方法采用两跨连续叠层梁作为铺装受力计算的基本模型。基于桥面沥青铺装疲劳开裂以纵桥向裂缝为主的工程实际,以及桥面沥青铺装的有限元计算结果,确定铺装顶面最大横向弯拉应变为控制指标,分别以铺装表面弯拉应变相等以及铺装底面弯拉应变相等的条件,利用弹性层状体系计算程序“BISAR”,计算得到铺装结构的“当量土基模量”,从而将桥面沥青铺装设计与一般沥青路面设计相联系,形成较为系统的桥面沥青铺装力学设计系统。采用桥面沥青铺装力学设计方法的算例表明,钢桥面的“当量土基模量”较大,计算精度较高,水泥混凝土桥面的“当量土基模量”非常小,对计算过程的数据精度有更高的要求。Different from the traditional experimental design method, a theoretical method for bridge asphalt pavement design is developed. Based on an analysis of the mechanical characteristics of bridge pavement by using the finite element method （FEM）, it is found that the ＇interval of ribs＇ and the thickness of deck are key factors to the stress in bridge pavement. Based on this conclusion, a continuous laminated beam has been employed as the basic model of bridge asphalt pavement. In practice, longitudinal cracking is the major fatigue effect on bridge pavement, and the result of FEM confirms that; the maximum transverse strain on the top of pavement is identified as the design index. The modulus of the corresponding base in an elastic multilayer system is calculated when the maximal transverse flexural-tensile strain on top or bottom of bridge pavement is equal to the flexural-tensile strain in normal asphalt pavement. The designs of bridge pavement and normal asphalt pavement are related to each other. The example indicates that the modulus of the corresponding base is larger when the new design method is employed for steel bridges than for concrete bridges, and higher accuracy is required in computations for the latter.

关 键 词：桥面沥青铺装 叠层连续梁 弹性层状体系 设计指标 设计系统 

分 类 号：U443.33[建筑科学—桥梁与隧道工程]