Bascule bridge is opened at the variable speed under the actual condition. In order to study the rules about dynamic responses of pavement layer under the variable speed,half steel bascule bridge deck pavement system model was established by the finite element method. The calculation results were compared with the past study at a constant speed. Through the analysis of the indoor shear test under the different temperatures on the inter laminar shear strength,safety factor was defined as the ratio of shear strength and shear stress. Different open means of security were evaluated by the safety factors. The study shows that the shear stress values of variable speed are greater than the values of constant speed. The angular acceleration effect on the stress between the layers should be considered in the design phase. In the two cases,with the temperature increasing the shear stress is decreased,the temperature influence of the structure layers on the shear stress is more obvious under the variable speed. When the bascule bridge is under the condition of high temperature,the angular acceleration should be appropriately reduced. Safety factor of variable speed is lower than uniform speed,in the design phase,variable speed work means should be used for research.%立转式开启桥在实际开启过程中是一个变速开启的运动过程,为了研究变速开启过程中铺装层的动力响应变化规律,采用有限元法,建立开启桥钢桥面铺装体系复合结构1/2桥模型,并与已研究的开启工况进行对比分析.通过室内剪切试验分析不同温度不同开启条件下的层间剪切强度,定义剪切强度与剪切应力的比值为安全系数,用以评价不同工况下的铺装体系复合结构安全性能.研究结果表明,变速开启状态下的剪应力值均大于匀速开启状态,在设计阶段建议考虑开启角加速度对层间应力的影响;随着温度升高,不论开启方式如何,层间剪应力均呈下降趋势,温度对层间剪应力的影响在变速开启状态下更为显著,建议开启桥在高温条件下工作时,适当延长开启时间,降低开启角加速度;采用变速开启方式安全系数比匀速低,建议在设计阶段采用变速开启方式进行研究.
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