中文摘要：

针对无砟轨道连续道床板,按截面等效单元思路,进行模型试验,测试各裂纹产生时的裂纹间距、轴向拉力、钢筋应力、裂纹宽度等情况。研究结果表明：道床板裂纹发展呈现为不稳定裂纹和稳定裂纹两个阶段;最小不稳定裂纹间距比理论计算值略小,且分布范围较大,造成各试件出现的裂纹数量不等;试件开裂时的拉力大多数小于其理论计算值,裂纹一旦产生,其附近钢筋应力突增;目前连续道床板配筋率偏低,强度储备不足,宜适当增加钢筋强度或配筋率。为保证结构安全,可取末次开裂轴力进行设计,或考虑混凝土强度的离散性,取一定保证率条件下的理论开裂轴力进行设计。

英文摘要：

In terms of equivalent cross section,the model experiment of continuous track slab was conducted to study the crack spacing,crack width,axial tension and steel bar stress for cracking.The results showed that the crack propagation process of concrete track slab can be divided into unstable stage and stable stage.The minimum unstable crack spacing was slightly smaller than that of theoretical calculation.With wider distribution of minimum unstable cracks,different specimens demonstrated varying cracks.The cracking axial tension of most specimens was smaller than that of theoretical calculation.The occurrence of cracks caused the sharp increase of stress on the nearby steel bars.The present reinforcement ratio of continues track slab is at low level and has not enough strength reservation,thus the steel bar strength or the reinforcement ratio should appropriately increase.In order to ensure the structure safety,the last cracking axial force should be used for structure design,or considering the discreteness of concrete strength,the theoretical cracking axial force with a certain guaranteed rate can be used for structure design.