为真实模拟车辆在桥面上的行走特征，研究轮载作用下钢板组合梁桥面板在墩顶负弯矩区的开裂特性，制作了 2×6 m两跨连续钢板组合梁模型试件，采用自主研发的轮胎式疲劳加载机往复行走进行疲劳加载，获得钢板组合梁桥面板裂缝发展和钢筋应力变化规律，对轮式往复加载与正弦加载进行对比分析。结果表明，钢板组合梁桥面板在墩顶负弯矩区会出现多条横向裂缝，同时在钢主梁顶部对应位置出现纵向裂缝;在 40～140 kN各级轮载作用下，桥面板墩顶上层横向钢筋应力最大值为 43 M Pa且比纵向钢筋应力大;混凝土应力最大值为 0。69 MPa，误差为4。17%，表明桥面板力学性能良好。真实轮载作用比正弦加载更为接近实际受力状态，体现了作用力在不同作用位置之间进行传递的过程，更能体现实桥上车辆的刹车和启动带来的冲击效应。
Experimental Study on Cracking Performance of Steel Plate Composite Girder Bridge Deck in Negative Moment Zone Based on Wheeled Loading
In order to truly simulate the vehicles driving on the bridge deck,and to study the cracking characteristics of steel plate composite beam deck in the negative moment zone at the pier top under wheel load,a continuous steel plate composite beam model specimen with spans of 2×6 m was used for fatigue test.The independently developed wheel-moving fatigue test machine is used for reciprocating fatigue loading,the crack development of steel plate composite beam deck and the change law of reinforcement stress are obtained.Also,the wheel reciprocating loading and sinusoidal loading are compared and analyzed.The results show that there are many transverse cracks in the negative moment area at the pier top,and longitudinal cracks at the corresponding position at the top of the steel main beam.Under the action of 40～140 kN wheel loading,the maximum stress of transverse reinforcement on the top of bridge deck pier is 43 MPa,which is greater than that of longitudinal reinforcement;the maximum concrete stress is 0.69 MPa,and the error is 4.17%,also the mechanical properties of bridge deck is good.The real wheel load action is closer to the actual stress state than sinusoidal loading,which reflects that the process of force transmission between different action positions.It can better reflect the impact effect brought by the braking and starting of vehicles on the real bridge.
bridge engineeringsteel plate composite girderwheel loadingnegative bending moment zone at the top of the pierfatigue cracksimpact effect
万方数据
维普
