车辆荷载谱作用下简支T梁力学性能

Mechanics performance of simple supported T-beam under vehicle load spectrum

由自编程序VLS(vehicle load spectrum——车辆荷载谱)构造随机车辆荷载谱,利用有限元程序将一般运行状态下的随机车辆荷载谱加载于简支T型钢筋混凝土梁上,模拟该梁在车辆荷载通过时的动力响应,得到了T梁位移时间历程曲线以及梁压区混凝土和拉区钢筋的应力时间历程曲线,并分析了压区混凝土和拉区钢筋的疲劳性能。结果表明:车辆荷载谱作用下T梁动挠度大于汽车-20和挂车-100静荷载作用下的挠度;压区混凝土及拉区钢筋的最大应力均介于汽车-20和挂车-100静荷载作用下的应力值之间;T梁疲劳寿命可达到2×106,但不超过2×107;拉区钢筋不能够满足混凝土规范关于疲劳验算的规定,需要进行验算。

The VLS （vehicle load spectrum） software written by the authors was utilizeded to establish the random vehicle load spectrum. The finite element program was adopted to simulate the dynamic response of the simple supported reinforced concrete T-beam under the vehicle load spectrum. The timedisplacement history of the beam, the time-stress history of the reinforcement in tensile region and the time-stress history of the concrete in compressive zone were obtained. The beam＇s fatigue property was studied. Under the vehicle load spectrum, the T-beam＇s dynamic deflection is bigger than its static deflection under design loads and that under checking computation loads. The stress of the reinforcement in tensile region and the stress of the concrete in compressive zone is checked under design loads and checking computation loads. Its fatigue life is bigger than 2× 10^6 , but less than 2 × 10^7. The stress of the reinforcement in tensile region is out of the range of the concrete code, so the stress of beam should be in the computed range. 3 tabs, 9 figs, 13 refs.