研究目的:研究客运专线箱梁端部裂纹的成因及其施工控制。
研究方法:针对铁路客运专线箱梁检测中普遍存在的端部纵向裂纹这一现象，通过有限元计算的方法，分 析裂纹产生的原因，从而提出箱梁施工控制方面应注意的间题。
研究结论:建议调整预应力的施工顺序，预、初张拉时，尽量避免张拉N2a及N1b孔道;严格控制存梁台 座的标高，定期观测不均匀沉降量，一旦发现，立即采取措施，避免扭矩的产生ffa强提梁孔附近的局部构造钢 筋，防止提、移梁时过大的局部应力导致该孔处裂纹的发生和扩展，注意提、移梁、落梁就位时采取必要措施， 尽量保持梁体两端承受均匀的自重作用，避免施工过程中产生扭转等附加应力。
Research purposes: The purposes are to do the researches on the causes for the crack on the end side of box girder for railway passenger dedicated line and its construction control.
Research methods: Aiming at the problem that crack often appear; an the end side of box girder for railway passenger dedicated line, the analyses of the cause for crack are made through adopting finite-element computing method and the issues for attention in construction control of box girder are presented.
Research conclusions: The following proposals，made:(1)It is necessary to adjust the construction order involved in Pre-stress and avoid stretching the drill ways of N2a and N1b as much a possible while pre-stretching and primary stretching，conducted; (2) It is necessary to well control the elevation of girder bearing bed and observe the uneven subsidence volume of the bed on fixed time, and if necessary, the measures should be taken so as to avoid appearance of movement of torque; (3) It is necessary to reinforce the structure around the girder lifting hole to avoid appearance and extension of cracks around the hole caused by the large stress while lifting and moving girder, and take some mearsures for keeping the even self weight effects on both ends of girder body w avoid appearance of movement of torque while lifting, moving and lowering the girder.
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