Zhang Yun, Yang Tao, Luo Tingyi, Chen Mingyu, Chen Xiaobin
Guangxi Beitou Highway Construction and Investment Group Co., Ltd., Nanning 530029, China.
College of Civil Engineering and Architecture, Guangxi University, Nanning 530004, China.
Materials (Basel). 2023 Mar 18;16(6):2427. doi: 10.3390/ma16062427.
Steel-concrete composite box beams are widely used in bridge engineering, which might bear transverse and longitudinal bending moments simultaneously under vehicle loads. To investigate the fatigue performance of joints between the steel girders and the top reinforced concrete (RC) slabs under transverse bending moments, a reduced scale joint between the weathering steel girder with the corrugated steel web (CSW) and the top RC slab was designed and tested under constant amplitude fatigue loads. Test results show that the joint initially cracked in the weld metal connecting the CSW with the bottom girder flange during the fatigue loading process. The initial crack propagated from the longitudinal fold to the adjacent inclined folds after the specimen was subjected to 7.63 × 10 loading cycles and caused the final fatigue failure. Compared with the calculated fatigue lives in the methods recommended by EC3 and AASHTO, the fatigue performance of the details involved in the joint satisfied the demands of fatigue design. Meanwhile, finite element (FE) models of joints with different parameters were established to determine their effect on the stress ranges at the hot spot regions of the joints. Numerical results show that improving the bending radius or the thickness of the CSW helps to reduce the stress ranges in the hot spot regions, which is beneficial to enhance the fatigue resistance of the investigated fatigue details accordingly.
钢 - 混凝土组合箱梁在桥梁工程中广泛应用，在车辆荷载作用下可能同时承受横向和纵向弯矩。为研究钢梁与顶部钢筋混凝土（RC）板之间的节点在横向弯矩作用下的疲劳性能，设计了一种缩尺比例的耐候钢梁与波形钢腹板（CSW）和顶部RC板之间的节点，并在常幅疲劳荷载作用下进行试验。试验结果表明，在疲劳加载过程中，节点最初在连接CSW与底部梁翼缘的焊缝金属处开裂。试件经历7.63×10次加载循环后，初始裂纹从纵向折痕扩展到相邻的倾斜折痕，导致最终疲劳破坏。与欧洲规范3（EC3）和美国公路与运输官员协会（AASHTO）推荐方法计算的疲劳寿命相比，节点所涉及细节的疲劳性能满足疲劳设计要求。同时，建立了不同参数节点的有限元（FE）模型，以确定其对节点热点区域应力范围的影响。数值结果表明，增大CSW的弯曲半径或厚度有助于降低热点区域的应力范围，从而相应地有利于提高所研究疲劳细节的抗疲劳能力。
