大跨径PC连续刚构桥长期下挠影响因素分析

发布时间：2018-03-02 08:37

本文关键词： 预应力混凝土连续刚构桥长期挠度影响因素仿真分析　出处：《中外公路》2014年04期 　论文类型：期刊论文

【摘要】：以栗子坪大桥——大跨径预应力混凝土连续刚构桥为工程实例,采用有限元程序Midas/Civil对其进行施工过程和运营阶段仿真计算,分析混凝土超方、预应力损失、混凝土收缩徐变、刚度损失等因素对大跨径预应力混凝土连续刚构桥跨中长期挠度的影响。计算结果表明:混凝土超方和桥面铺装施工误差导致的自重增加均可引起桥梁跨中长期挠度增加,后者超重使桥梁跨中长期挠度增加更大;预应力损失对桥梁跨中长期下挠影响非常显著,其中顶板束预应力损失影响最大,其次是腹板束,底板束影响最小;桥梁跨中长期挠度与终极徐变系数、环境相对湿度的变化有很大关系;梁体刚度降低使桥梁跨中长期挠度增加较多,且早期刚度的降低对桥梁跨中挠度增加影响较大。
[Abstract]:Taking Liziping Bridge-long span prestressed concrete continuous rigid frame bridge as an engineering example, the construction process and operation stage of the bridge are simulated by finite element program Midas/Civil, and the concrete oversquare, prestress loss, shrinkage and creep of concrete are analyzed. The effect of stiffness loss and other factors on the long-span prestressed concrete continuous rigid frame bridge span mid-long term deflection. The calculation results show that the increase of self-weight caused by the oversquare concrete and bridge deck pavement construction error can cause the bridge span mid-long term deflection increase. The overweight of the latter makes the bridge span deflection increase in the medium and long term, and the influence of prestressed loss on the bridge span mid- and long-term deflection is very significant, among which the prestressed loss of roof beam is the biggest, the web beam is the second, and the influence of bottom plate bundle is the least. The medium and long term deflection of bridge span is related to the ultimate creep coefficient and the change of environmental relative humidity, and the reduction of beam stiffness increases the medium and long term deflection of bridge span, and the reduction of early stiffness has a great influence on the increase of midspan deflection.
【作者单位】：郑州大学土木工程学院;
【分类号】：U448.23

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