Influence of Interface Crack on Impact Dynamic Properties of CRTS III Slab Track-Subgrade System
-
摘要: 为了研究板边离缝对高速铁路基础结构动力特性的影响,利用CRTS III型板式轨道-路基全尺寸试验模型开展了落轴试验,实测了轨道板与自密实充填层一侧界面处离缝的几何分布,并利用ANSYS/LS-DYNA有限元软件建立了相应的动力有限元分析模型,分析了板边离缝对轨道和路基结构冲击动力特性的影响规律,并利用相应的试验结果对数值结果进行了对比验证. 研究结果表明:轨道板和自密实层界面处单侧离缝的平均宽度和平均高度分别为28.18 cm和2.15 mm;板边离缝宽度对基础结构动力特性的影响要大于离缝高度;在0~800 mm的范围内,随着离缝宽度的增加,轨道和路基位移以及钢轨加速度、轨道板加速度和基床底层加速度都持续增加,其中轨道板的位移和加速度的增幅均为最大,分别为56.8%和143.3%,充填层、支承层和基床表层的垂向加速度随离缝宽度的增加先增大后减小,当离缝尖端扩展至钢轨正下方附近时达到最大值;在0~3 mm的范围内,轨道和路基垂向位移与加速度均随离缝高度的增大而略微增加,最大增幅分别为8%和12%;越靠近离缝界面层面,离缝高度对其冲击动力特性的影响也越显著.Abstract: To investigate the influence of the interface crack on the dynamic characteristics of high-speed railway infrastructure, a wheel-drop test was performed using the full-scale experimental platform of CRTS III ballastless track-subgrade system. The distribution of the one-sided interface crack between the slab and self-compacting concrete layer was measured and summarised. The 3D dynamic finite element model of the CRTS III track-subgrade system with a one-sided interface crack was established using the ANSYS/LS-DYNA software. The influence of the interface crack subjected to the wheel-drop load was investigated on the basis of comparisons between the experimental data and numerical results. The results indicate that the average width and height of the interface are 28.18 cm and 2.15 mm, respectively. The crack width has a stronger effect than the crack height on the infrastructure dynamic reaction. When the crack width increases within a range of 0 to 800 mm, all the displacements of the infrastructure and the accelerations of the rail and slab increase proportionally with the increase of the crack width. When the crack width approaches the distance between the rail and slab edges in the lateral direction, the accelerations of the filling layer, concrete basement, and subgrade reach their respective maxima. The maximum icrements of the displacement and the acceleration for the track and the subgrade are both occurred in the slab, which are respectively 56.8% and 143.3%. All the displacements and accelerations of the track and subgrade slightly increase with the increase of the crack height from 0 to 3 mm, and the maximum increments are 8% and 12%, respectly. The influence of the crack is more remarkable on the dynamic properties with the decrease of the distance between the infrastructure level and the crack locsation.
-
Key words:
- ballastless track /
- subgrade /
- interface crack /
- dynamic characteristics /
- wheel-drop test /
- numerical analysis
-
表 1 轨道和路基结构尺寸和材料参数
Table 1. Size and material parameters of track-subgrade structure
参数 钢轨 轨道板 自密实层 支承层 基床表层 基床底层 路基本体 宽度/m ― 2.5 2.5 3.1 6.0 6.0 6.0 高度/m ― 0.19 0.09 0.24 0.40 2.60 2.00 密度/(kg•m-3) 7 850 2 500 2 500 2 500 1 950 1 800 1 700 弹性模量/GPa 206.00 35.50 32.50 28.00 0.25 0.20 0.15 泊松比 0.30 0.20 0.20 0.20 0.30 0.25 0.25 表 2 轨道-路基动力响应幅值比较
Table 2. Comparison of maximum values of dynamical reactions for track-subgrade
项目 钢轨加速度/(×g) 轨道板加速度/(×g) 自密实层加速度/(×g) 支承层加速度/(×g) 基床表层动应力/kPa 数值结果 265.00 3.33 2.96 1.78 25.00 试验结果 263.00 3.31 3.18 1.95 23.20 相对误差/% 0.7 0.6 7.4 9.5 7.2 -
杨俊斌,刘学毅,刘永孝,等. Ⅰ型轨道板端离缝对轨道结构及车辆动力特性的影响[J]. 西南交通大学学报,2014,49(3): 432-437YANG Junbin, LIU Xueyi, LIU Yongxiao, et al. Influence of seam in type I slab ends on dynamic characteristics of track and vehicle[J]. Journal of Southwest Jiaotong University, 2014, 49(3): 432-437 朱浩,徐浩,谢铠泽,等. CA砂浆离缝对CRTS Ⅱ型板式轨道的影响研究[J]. 铁道标准设计,2013,12(12): 35-39ZHU Hao, XU Hao, XIE Kaize, et al. Influence on CRTS II slab track caused by the de-bonding of emulsified cement asphalt mortar[J]. Railway Standard Design, 2013, 12(12): 35-39 徐浩,刘霄,徐金辉,等. 温度作用下轨道板与CA砂浆离缝对CRTSⅡ型板式轨道的影响分析[J]. 铁道标准设计,2013,9(9): 9-12XU Hao, LIU Xiao, XU Jinhui, et al. Influence on CRTS II slab track structure caused by the debonding between slab and CA mortar under the action of temperature load[J]. Railway Standard Design, 2013, 9(9): 9-12 SONG Xiaolin, ZHAO Chunfa, ZHU Xiaojia. Temperature induced deformation of CRTS II slab track and its effect on track dynamical properties[J]. Science China Technology Science, 2014, 57(10): 1917-1924 齐少轩,任娟娟,刘学毅. 桥上CRTSII型道岔板砂浆离缝影响特性研究[J]. 工程力学,2015,32(6): 124-132QI Shaoxuan, REN Juanjuan, LIU Xueyi. Influence of debonding on the performance of CRTS II slab track turnouts on large bridges[J]. Engineering Mechanics, 2015, 32(6): 124-132 刘钰,赵国堂. CRTS Ⅱ型板式无砟轨道结构层间早期离缝研究[J]. 中国铁道科学,2013,34(4): 1-7LIU Yu, ZHAO Guotang. Analysis of early gap between layers of CRTS II slab ballastless track Structure[J]. China Railway Science, 2013, 34(4): 1-7 刘少飞. CRTS Ⅲ型板式无砟轨道层间离缝原因分析[J]. 铁道建筑,2017(4): 106-109 杨政. CRTSⅢ型板式轨道层间离缝下的受力及维修限值研究[D]. 成都: 西南交通大学, 2014 全毅,刘学毅,杨荣山. CRTSⅢ型板式轨道层间离缝下门型筋合理布置研究[J]. 铁道科学与工程学报,2016,13(3): 407-413QUAN Yi, LIU Xueyi, YANG Rongshan. Reasonable arrangement of door type steel of interlayer gap for CRTS Ⅲ slab track[J]. Journal of Railway Science and Engineering, 2016, 13(3): 407-413 邵丕彦,李海燕,吴韶亮,等. CRTS Ⅰ型轨道板温度变形及与砂浆垫层间离缝的测试研究[J]. 中国铁道科学,2013,34(2): 18-22SHAO Piyan, LI Haiyan, WU Shaoliang, et al. Measurement and research on temperature warping of CRTS I track slab and crack between track slab and cement asphalt mortar cushion[J]. China Railway Science, 2013, 34(2): 18-22 姜子清,施成,赵坪锐. CRTS Ⅱ型板式无砟轨道砂浆层离缝检查及伤损限值研究[J]. 铁道建筑,2016(1): 53-58 王明昃,尹镪,朱胜阳,等. 冲击荷载作用下CRTS III 型板式轨道-路基系统动力特性研究[J]. 中国科学: 技术科学,2014,44(7): 722-728WANG Mingze, YIN Qiang, ZHU Shengyang, et al. Dynamic analysis of CRTS III slab track-subgrade system under impact load[J]. Scientia Sinica: Technologica, 2014, 44(7): 722-728 曾志平,罗俊,刘斌,等. 界面离缝对CRTS Ⅲ型板式轨道动力特性的影响[J]. 铁道工程学报,2016,33(3): 34-38, 104ZENG Zhiping, LUO Jun, LIU Bin, et al. Influence of interface bond damage on the dynamic characteristic of CRTS III slab track[J]. Journal of Railway Engineering Society, 2016, 33(3): 34-38, 104 裴承杰,宋小林,吕天航. CRTS Ⅲ 型无砟轨道基础结构冲击试验与数值分析[J]. 铁道科学与工程学报,2017,14(3): 425-436PEI Chengjie, SONG Xiaolin, LÜ Tianhang. Full-scale model impacting experiments and numerical analysis on CRTS III ballastless track-subgrade system[J]. Journal of Railway Science and Engineering, 2017, 14(3): 425-436 吕天航. 板边离缝对CRTS III型轨道-路基系统动力特性影响研究[D]. 成都: 西南交通大学, 2017