城市高架混凝土现浇变宽梁桥横梁开裂处置措施及效果分析

针对某软土地基城市高架混凝土现浇变宽箱梁桥施工过程中出现的横梁开裂问题，结合裂缝分布特点，提出了相应的加固处置措施，并采用空间杆系模型与ANSYS实体有限元模型相结合的方式对其加固效果进行分析。研究结果表明：与加固前相比，加固后横梁正截面抗弯承载能力提升了9.0%，斜截面抗剪承载力提升了38.9%；加固后横梁正截面抗弯、斜截面抗剪以及裂缝断面直剪承载力均满足要求，且横梁正截面和斜截面抗裂性均满足要求，加固效果较为显著。横梁荷载试验结果表明，加固后横梁总体抗弯工作性能和开裂位置附近的抗剪工作性能良好。所提出的增大截面和增设预应力综合加固方案，可为其他工程提供参考。

Treatment Measures and Effect Analysis on Beam Cracking of Urban Elevated Concrete Cast-in-situ Widening Beam Bridge

In order to solve the problem of beam cracking during the construction of an urban elevated concrete cast-in-situ widening box beam bridge in soft soil foundation, combined with the characteristics of crack distribution, the corresponding disposal measures are proposed, and its reinforcement effect is analyzed by the method of combining the space rod system model and the ANSYS solid finite element model. The results show that the anti-bending bearing capacity of of the positive section of the beam is increased by 9.0%, and the shear bearing capacity of the oblique section is increased by 38.9% compared with that before the reinforcement. The bending resistance of positive section, the shear resistance of the oblique section and the direct shear bearing capacity of the crack section all meet the requirements after the reinforcement of the beam. And the reinforcement effect is more significant. The load test results of the reinforced beam show that the overall bending performance and the shear performance near the cracking position of the reinforced beam are good. The enlarged section and additional prestressed comprehensive reinforcement scheme can provide reference for other projects.