基于有限元的水泥混凝土道面脱空分析与评价

Analysis and Evaluation of Cement Concrete Pavement Caving Based on Finite Element

针对道面不同位置、不同宽度的脱空,以B767-300机型作用下的5 m×5 m道面板为例,构建了相应的有限元模型,对板内最大弯拉应力随脱空状态的变化规律进行了分析,并基于此,提出了以脱空宽度为评价指标的脱空评价标准。分析结果表明:对于板边脱空,不同接缝传荷能力下的最大弯拉应力随脱空宽度增大,近似线性增大;对于板角脱空,接缝传荷能力对板内最大弯拉应力的数值和位置有较大影响,接缝传荷能力为“中”等级时,最大弯拉应力相对较小;由应力阈值推算出的脱空宽度阈值可对道面进行评价。

A corresponding finite element model is constructed for the caving at different positions and sizes of the roadway surface,taking the 5 m×5 m tunnel panel under the action of B767-300 as an example.The variation of the maximum flexural and tensile stress in the plate with the caving state is analyzed.Based on this,a caving evaluation criterion based on the caving size is proposed.The analysis results show that the maximum flexural and tensile stresses increase approximately linearly with the size of the plate side.For plate angle caving,the joint load transfer capacity has a great influence on the value and position of the maximum flexural tensile stress in the plate,and the maximum flexural tensile stress is relatively small when the joint load transfer capacity is"medium".The threshold evaluation criterion of the void size can be calculated from the stress threshold.