连续钢混组合梁负弯矩区处理措施

Dispose Measures for Continuous Steel Combination Beam in Hogging Negative Moment Region

钢混组合梁有承载力高、抗震性能好、方便施工、缩短工期、节省材料且便于安装管线等优点,在各地桥梁建设中已经大量应用。但在使用过程中,连续钢混组合梁在负弯矩区会产生混凝土受拉、钢梁受压的不利情况,造成混凝土开裂,导致组合梁刚度降低和耐久性下降。总结归纳了多种连续钢混组合梁负弯矩区的处理措施,包括预加荷载法、支座预顶升法、施加预应力法、配筋限制混凝土裂缝宽度法、后结合预应力混凝土桥面板法、钢梁底板浇注混凝土法、增强钢混结合强度法,为改善该类桥梁负弯矩区的设计和施工提供了借鉴和参考。

The steel and concrete combination beam has the advantages of high bearing capacity,good anti-seismic performance,convenient construction,short construction period,saving in material and convenient to install the pipeline,etc.,which has been largely applied in bridge construction everywhere. The continuous steel and concrete combination beam may causes disadvantages of the tensioned of concrete and the pressed of the steel beam,which leads to the decline of stiffness and durability of the combination beam in using period. Summarizing the depose measures for multiple continuous steel and concrete combination beam in hogging negative moment region,including pre- load method,bearing pre- jacking method,method of imposing prestress,method of reinforcement limit distress in concrete,concrete bridge panel method of posterior association prestress,method of steel floor pouring concrete,method of improve steel and concrete combination strength. To improve the design and construction of this kind of bridge in hogging negative moment region,providing a model and reference.