中文摘要：

研究目的：目前轨道板与CA砂浆层离缝损伤是我国CRTS 1型板式无砟轨道主要损伤形式，本文为研 究砂浆层离缝损伤机理，制作混凝土和砂浆复合试件进行劈拉和剪切模型试验，采用数字图像相关（DIC）技 术得到加载过程的层间应变场分布，分析得到内聚力模型参数，并采用有限元软件计算内聚力模型参数且与 试验结果进行对比验证，得到轨道板与砂浆层间力学特性及其破坏模式。 研究结论：（ 1） DIC技术能较好地描述复合试件的层间应变场分布，以及层间损伤、裂纹萌生、扩展及破 坏的全过程；（2）轨道板与砂浆层间粘结破坏属脆性破坏，层间法向和切向张力-位移关系均表现为双线 性关系；（3）轨道板与砂浆层间参数可取法向内聚强度1.792 MPa、界面刚度708. 485 MPa/mm、临界断裂能 0.025 2 mJ/mm2，切向内聚强度0.956 MPa、界面刚度63.039 MPa/mm、临界断裂能0.018mJ/mm2;（4）本研 究成果可用于分析轨道板与砂浆层间损伤开裂行为，可为Ⅱ型板式轨道结构的设计及维修提供理论依据。

英文摘要：

Research purposes： Now the contact loss between slab and CA mortar is the main damage type of Chinese CRTS II slab track,in order to figure out the damage mechanics of contact loss,the composite specimens of concrete and CA mortar were used to conduct the splitting tensile and shear test. The stress distribution of the interface was obtained with digital image technology （ DIC ）, and then the parameters of cohesive model were achieved. The interface mechanical properties and failure mode between slab and CA mortar were obtained through comparing with the cohesive finite element model analysis results and the experiment results. Research conclusions：（1） The DIC technology can clearly describe the stress distribution of the composite specimens interface and its whole failure stage including the interface damage evolution,the formation and propagation of crack. （2 ） The bond failure between track slab and CA mortar is brittle fracture,and the interface normal stress - displacement and tangential stress - displacement are both bilinearity. （ 3 ） The cohesive model parameters between the track slab and CA mortar were recommended as follows： the normal cohesive strength is 1.792 MPa,the normal interface stiffness is 708. 485 MPa/mm,the normal critical fracture energy is 0. 025 2 mJ/mm2,the tangential cohesive strength is 0. 956 MPa, the tangential l interface stiffness is 63.039 MPa/mm,the tangential critical fracture energy is 0.018 mJ/mm2. （4） These results can be used to analyze the interface cracking behavior between slab and CA mortar,and provide theoretical basis for CRTS II slab track design and maintenance.