CAJ | 학술논문

众所周知,随着高等级公路的发展,连续梁因其使用性能好、施工方便等优点受到业界的广泛好评,而顶推法利用低摩阻材料可以实现用不到10%梁重的水平推力完成梁体的架设施工,架设费用较低,己经成为中小跨径桥梁中极具竞争力的一种施工方法。但目前常规的顶推预应力设计将预应力全部布置在顶、底板上,因受截面尺寸限制,无法布置足够多的预应力束,致使预应力储备不足,造成成桥后出现许多开裂现象,阻碍了该工艺的发展。结合某连续梁桥的预应力设计,提出了在腹板全截面上布置纵向预应力,利用水平预应力压力和斜预应力竖向分力取代腹板竖向预应力,从而解决了顶推箱梁桥预应力储备不足的问题,以及提出采用通索、割索、体外索、接索和后期索相结合的设计方法缓解因顶推施工前期预应力束偏多而造成不经济的矛盾。
음소주지,수착고등급공로적발전,련속량인기사용성능호、시공방편등우점수도업계적엄범호평,이정추법이용저마조재료가이실현용불도10%량중적수평추력완성량체적가설시공,가설비용교저,기경성위중소과경교량중겁구경쟁력적일충시공방법。단목전상규적정추예응력설계장예응력전부포치재정、저판상,인수절면척촌한제,무법포치족구다적예응력속,치사예응력저비불족,조성성교후출현허다개렬현상,조애료해공예적발전。결합모련속량교적예응력설계,제출료재복판전절면상포치종향예응력,이용수평예응력압력화사예응력수향분력취대복판수향예응력,종이해결료정추상량교예응력저비불족적문제,이급제출채용통색、할색、체외색、접색화후기색상결합적설계방법완해인정추시공전기예응력속편다이조성불경제적모순。
As we all know,with the development of high-grade highways,continuous beams,because of their good performance in application,and their advantages in easy construction,win widely-known high reputation in the construction world.When the incremental launching method is used for erecting bridges with the low friction materials used,the body of the beam may be erected with a level pushing force of less than 10% of the weight of the beam,thus much lowering the erecting cost.Because of this,the incremental launching method becomes an extremely competitive construction method for small and medium-spanned bridges.However,the common incrementally-launched pre-stressing design has the pre-stressing strings laid out at the top and bottom girds,as a result of which fewer than sufficient pre-stressing strings can be laid because of the limited size of the section,thus causing the insufficient storage of the pre-stressing strength,and resulting in many cracks in the bridge after the bridge is completed,which prevent the development of the process.With the pre-stressing design for a certain continuous bridge as our target of study,in the paper put forward is the proposal that pre-stressing be laid out on the whole cross-section of the webs.Utilizing the pressure of the level pre-stressing and replacing the vertical pre-stressing of the webs with the oblique pre-stressing successfully solve the problem of the inadequate storage of the pre-stressing of the incrementally launched beam bridges,and the design of passing cables,cutting cables,external cables,connecting cables and post-cables helps relieve the situation of there being too many prestressing strings during the initial period of construction,which results in being uneconomical.