摘要
针对目前斜拉桥环向预应力施工中实际伸长量偏差超出规范要求±6%的现象,通过内蒙古小沙湾黄河特大桥索塔锚固区足尺模型试验,分析了影响张拉伸长量的主要因素。为进一步探究钢绞线受力不均匀这一主要因素的影响,建立了钢绞线在波纹管内排列形式的三种简化模型,分析了钢绞线张拉时波纹管内部钢绞线的伸长状态及具体行为。另外,就采用逐根穿束工艺的钢绞线在张拉时易出现打搅的现象提出了一些意见和建议,希望实际施工中在考虑张拉伸长量修正的基础上加强对小半径环向预应力钢绞线实际受力状态的关注。
For the phenomenon that the error of stretching elongation in annular prestress technology always exceeds the limitation of 6% in cable-stayed bridge construction, the main factors which lead to the stretching elongation are analyzed through a full-size model test of cable-pylon anchorage zone of Xiaoshawan Yellow River grand bridge in Inner Mongolia. To further explore the influence of the main factor （uneven stress of stranded steel wire）, 3 simplified models of the arrangement form of stranded steel wire inside bellow are built, and the stretching elongation and behavior of stranded steel wire inside bellow during stretching are analyzed. Moreover, for the easily winding phenomenon of steel strands during stretching using strand by strand pulling technique, some suggestions are given. It is hoped that the real forces of small radius annular prestress stranded steel wires should be taken much more attention on the basis of stretching elongation correction in construction.
出处
《公路交通科技》
CAS
CSCD
北大核心
2014年第7期103-107,共5页
Journal of Highway and Transportation Research and Development
关键词
桥梁工程
钢绞线行为
足尺模型试验
张拉伸长量
环向预应力
bridge engineering
stranded steel wire behavior
full-size model test
stretching elongation
annular prestress
