装配式空心板桥由于铰缝损伤而出现“单板受力”问题,为增强梁板间的横向连接,提出型钢-混凝土组合加固技术,以寿昌江二号桥(装配式预应力钢筋混凝土简支空心板桥)为背景,简述该技术在该桥中的应用.型钢-混凝土组合加固是在沿梁底铰缝两侧设置剪力键,纵向锚贴U形钢板,并在U形钢板和铰缝间灌注高强自密实灌浆料.为检验加固效果,对该桥第2跨进行加固前、后的静载试验.结果表明:加固后该桥跨中应变平均降低20％,挠度平均降低25％以上,桥梁的刚度有所提升;加固后1号板的横向分布系数增大,1号与2号梁板间的铰缝损伤得到修复.实践证明,型钢-混凝土组合加固技术可增强主梁间的横向联系,能有效解决“单板受力”问题.%The problem of the "single slab loading bearing" occurs in the assembled hollow slab bridge owing to the damage of the hinge joints on the bridge.To enhance the transverse connection of the slabs,the shaped steel and concrete composite reinforcement technique is proposed herewith.The Shouchang River Bridge No.2 (an assembled prestressed concrete simply-supported hollow slab bridge) is cited as an example and the applying of the reinforcement technique for the first time to the bridge is briefly presented.The principle of the shaped steel and concrete composite reinforcement is to arrange the shear keys along both sides of the hinge joints at the bottom of the cross beams,anchor the U-shaped steel plates in the longitudinal direction and fill the highstrength and self-compacting grouting material between the plates and hinge joints.To check the effect of the reinforcement,the static load tests have been made for the second span of the bridge before and after the reinforcement of the span.The results show that the strain at the midspan of the bridge after the reinforcement of the bridge averagely decreases by 20％,the deflection averagely decreases by more than 25％ and the rigidity of the bridge is raised to some extent.The load transverse distribution coefficient of the slab 1 increases after the reinforcement and the damage of the hinge joint between the slabs 1 and 2 is well repaired.Practice proves that the reinforcement technique as proposed can improve the transverse connection between the cross beams and the slabs and can effectively resolve the problem of the "single slab loading bearing".
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