中文摘要：

运用ANSYS有限元软件,建立长大温度跨混凝土桥上CRTSⅡ型纵连板式无砟轨道三维模型,分析无砟轨道结构的力学性能及底座板设计荷载组合的适应性。结果表明：制动工况下长大温度跨主要影响剪力齿槽的受力,最大温度跨150,290和450m连续梁相邻简支梁剪力齿槽的剪力分别为通常区域简支梁的1.12,1.28和1.33倍;当梁体从0℃升或降20℃时,最大温度跨350m连续梁相邻5～8跨简支梁区域内的无砟轨道砂浆和剪力齿槽的受力约为简支梁的1.4～2.2倍,底座板和轨道板的受力则达到简支梁的4.6～7.9倍,因此,在设计时应重点关注与最大温度跨相邻5～8跨简支梁区域内无砟轨道轨道板、底座板、砂浆及剪力齿槽,并采取相应的加强措施;最大温度跨350m连续梁桥上无砟轨道底座板内的伸缩附加力约为底座板既有设计荷载组合值的1/3～1/2,因此长大温度跨桥上无砟轨道底座板的设计荷载组合应考虑梁体的伸缩附加力。

英文摘要：

With finite element software ANSYS,a three dimensional model of CRTS Ⅱ slab ballastless track on long temperature span concrete bridge was established to analyze the mechanical properties of its structure and the adaptability of the design load combination of base slab.The results showed that,under braking condition,long temperature span mainly affected the mechanical performance of shear notch.The shears of the shear notches between the simply supported girders and the adjacent continuous girders with the maximum temperature spans of 150,290 and 450 m were respectively 1.12,1.28 and 1.33 times of those on normal simply supported girders.When the temperature of girder body rose or dropped 20 ℃ from 0 ℃,the stress of the ballastless track mortar and shear notch within the range from the continuous girder with the maximum temperature span of 350 mto the adjacent 5～8 spans of simply supported girders was 1.4～2.2 times of those on normal simply supported girder.The stress of base slab and track slab arrived at 4.6～7.9 times of simply supported girder.Accordingly,during the design,more attention should be paid to ballastless track slab,base slab,mortar and shear notch within the range from the continuous girder with the maximum temperature span to the adjacent 5～8 spans of simply supported girder,and corresponding strengthening measures should be taken.The additional expansion and contraction force in the base slab of ballastless track on the continuous beam bridge with the maximum temperature span of 350 m was about 1/3～1/2 of the existing design load combination of base slab.Therefore,the additional expansion and contraction force of girder body should be considered in the design load combination for the base slab of ballastless track on long temperature span bridge.