增铺双钢混凝土层加固桥梁力学特性分析及其工艺

Mechanical Analysis and Construction Process of Bridge Reinforcement via Additional RC with Bars and Steel Fibres

东莞北大桥运营后,其T主梁间的湿接桥面板处出现了渗水、穿孔等病害.增铺双钢混凝土桥面补强层加固法很适宜对该桥的加固.研究了该加固方法的有关参数和工艺.利用MIDAS-Civil软件建模分析了桥梁的受力特性,模拟了新、旧混凝土的结合,考虑了超载和混凝土的收缩徐变,得出了双钢混凝土桥面铺装层最佳厚度和锚筋间距.把微裂缝视为通缝和铰缝,只需剔除严重病害的原现浇桥面板,即可处置现存病害.加固法的施工工艺在本桥加固中得以成功采用.

After the operation of the Northern Bridge in Dongguan,such troubles as seepage and openings were found at the deck slabs wet-jointed between T-beams.For such troubles,the additional RC paving reinforcement with both steel fibres and bars is regarded as highly applicable to the bridge.Investigates the parameters and construction process relevant to the method of reinforcement.The numerical software MIDAS-Civil was thus used to model the mechanical behavior of the bridge.The interconnection between the new and existing concrete bridge structures was simulated taking account of the overload and shrinkage creep of concrete.The spacing between anchoring bars and optimal thickness of concrete bridge deck were then given.Assuming that the microcracks are continuous and hinged joints,a conclusion is drawn that getting rid of the existing deck slab cast in site,which was the source of the troubles as above,the bridge will be improved greatly.The construction process as a way to reinforce the bridge has been accepted successfully to use.