关键词: 钢-混凝土连续组合梁, 非张拉预应力技术, 负弯矩区, 配重, 裂缝宽度, 变形

Abstract:

By analyzing the loading stages of the continuous steel-concrete composite beams with 2-5 spans,some key parameters of the non-tension prestressing technology of the composite beams,such as the counterweights and their arrangement,as well as the post-cast length of concrete in the negative-moment region,are investigated.Then,the calculation methods of crack width in the negative-moment region and mid-span deformation of the composite beams are discussed after the removal of the counterweights.It is suggested that the reverse deflection induced by the non-tension prestressing can be obtained through two steps,namely,converting the reverse loads resulting from weight removing to the full-span uniform ＂equivalent＂ ones,and then calculating the deflections under the ＂equivalent＂ loads.With this two-step method,the requirements of practical engineering are satisfied well,and the maximum relative error of deflection keeps within 15%.

Key words: continuous steel-concrete composite beam, technology of non-tension prestressing, negative-moment moment region, weights, crack width, deformation