温度和动载作用下连续梁桥桥面铺装层力学分析

发布时间：2019-06-02 13:10

【摘要】：桥面铺装层力学分析中普遍采用的方法是在桥梁结构中截取局部梁段加上适当的约束来分析铺装层在静载作用下的受力状况，对于桥梁结构，除了要考虑静载引起的变形和应力外，还需要考虑外部激发的动力响应，大跨径混凝土连续梁桥在温度作用下往往有较大的变形。本论文通过对实桥桥面铺装层温度场的现场观测结果与模拟结果对比，验证了利用ABAQUS有限元软件可以正确地描述桥面铺装层温度场分布。采用自行研制的层间抗剪强度剪切仪对桥面铺装层层间抗剪强度进行了室内试验。为了准确分析桥面铺装层的受力状态，，本文针对温度及移动荷载共同作用下连续梁桥桥面铺装层受力情况进行数值模拟分析，为桥面铺装层设计提供参考。本文以动载理论和温度场理论为基础，运用有限元法，应用通用有限元软件ABAQUS建立了三跨混凝土连续箱梁桥三维有限元模型，采用半波正弦荷载加载并考虑温度的作用，进行沥青混凝土桥面铺装层在温度与移动荷载共同作用下的力学时程响应分析，并分析降温幅度、车速、超载、铺装层模量、桥梁跨径以及铺装层厚度对桥面铺装层受力的影响。研究表明,热量在桥面铺装层中传递时存在滞后现象，且在箱梁桥腹板位置对应的铺装层处温度变化波动比较明显。在温度和移动荷载共同作用下混凝土连续梁桥桥面铺装层在桥梁中跨支座处受力最不利，其最大拉应力发生在铺装层表面,最大剪应力发生在铺装层间。降温幅度越大桥面铺装层拉应力越大，超载比例越大铺装层拉应力极值与铺装层剪应力极值越大，铺装层拉应力极值与铺装层剪应力极值随车速增大而减小，并且铺装层拉应力极值与剪应力极值在铺装层厚度一定范围内随铺装层厚度增大而减小。以沥青混凝土桥面铺装层层间剪切试验以及公路沥青路面设计规范为基础,提出以沥青混凝土铺装层拉应力和剪应力作为桥面铺装层结构设计的主要指标。根据温度与动载共同作用下桥面铺装层受力分析结果，综合考虑应力指标以及经济因素得到不同跨径下铺装层合理厚度范围。
[Abstract]:The commonly used method in the mechanical analysis of bridge deck pavement is to intercept the local beam section in the bridge structure and add appropriate constraints to analyze the stress condition of the pavement layer under static load. For the bridge structure, In addition to considering the deformation and stress caused by static load, it is also necessary to consider the dynamic response excited by external excitation. Long-span concrete continuous beam bridges often have large deformation under the action of temperature. In this paper, by comparing the field observation results with the simulation results, it is verified that the temperature field distribution of bridge deck pavement can be correctly described by using ABAQUS finite element software. The interlaminar shear strength of bridge deck pavement was tested in laboratory by using the interlaminar shear strength shearing instrument developed by ourselves. In order to accurately analyze the stress state of bridge deck pavement, this paper carries on the numerical simulation analysis to the continuous beam bridge deck pavement under the action of temperature and moving load, which provides a reference for the design of bridge deck pavement. In this paper, based on the dynamic load theory and temperature field theory, the three-dimensional finite element model of three-span concrete continuous box girder bridge is established by using the finite element method and the general finite element software ABAQUS. The three-dimensional finite element model of three-span concrete continuous box girder bridge is loaded by half-wave sinusoidal load and the effect of temperature is considered. The mechanical time history response of asphalt concrete bridge deck pavement under the action of temperature and moving load is analyzed, and the cooling amplitude, speed, overload and pavement modulus are analyzed. The influence of bridge span and pavement thickness on the stress of bridge deck pavement. The results show that there is a lag phenomenon in the heat transfer in the bridge deck pavement, and the temperature fluctuation is obvious in the pavement layer corresponding to the web position of the box girder bridge. Under the action of temperature and moving load, the stress of concrete continuous beam bridge deck pavement is the most unfavorable at the span support of the bridge, the maximum tensile stress occurs on the surface of the pavement layer, and the maximum shear stress occurs between the pavement layers. The larger the cooling amplitude is, the greater the tensile stress of the pavement layer is, the larger the overloading ratio is, the greater the extreme value of tensile stress and shear stress of pavement layer is, and the extreme value of tensile stress of pavement layer and shear stress of pavement layer decrease with the increase of vehicle speed. The extreme values of tensile stress and shear stress of the pavement decrease with the increase of the thickness of the pavement in a certain range of the thickness of the pavement. Based on the interlaminar shear test of asphalt concrete bridge deck pavement and the design code of highway asphalt pavement, the tensile stress and shear stress of asphalt concrete pavement are put forward as the main indexes of bridge deck pavement structure design. According to the stress analysis results of bridge deck pavement under the action of temperature and dynamic load, the reasonable thickness range of pavement layer with different span is obtained by considering the stress index and economic factors.
【学位授予单位】：内蒙古工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U443.33

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