大跨度T型刚构桥体外预应力加固设计

针对苏丹Burri桥大跨度预应力混凝土铰接T型刚构悬臂端严重下挠的问题,采用体外预应力技术进行加固设计,说明利用体外预应力加固同类大跨度结构的设计原则、加固要点和工艺流程,并采用有限元软件分析加固后T型刚构桥的静力性能。     

T型刚构桥水平转体法施工的研究与应用

简要介绍了T型刚构桥水平转体法施工的工作原理以及施工工艺，并通过两座T型刚构桥简要地阐述了水平转体施工的工艺特点，经实践证明，转体施工工艺简便，应用较广，能有效地节约投资，节省工期。     

预应力T型刚构桥的检测及加固

通过对主跨为预应力T型刚构的安徽省某桥进行详细的检测,获得了现状数据,在此基础上对该桥做了相关结果分析,掌握了该桥的工作状况,并按照远景的使用要求,提出了合理的加固改造方案。同时针对出现的接缝质量问题,对接缝位置的选择和预应力筋锚固端的处理提出了相关建议。     

T型刚构矮塔斜拉加固变体系研究

为了解决国内T型刚构桥梁出现的箱室底板正应力超限、截面主拉应力超限、最大悬臂端下挠严重的问题,提出了矮塔斜拉变体系加固方案,研究T型刚构桥在变体系后桥梁是否得到预期的加固效果结果表明,加固后桥梁梁体截面顶底板拉压应力有一定储备,主拉压应力在规定值以内,满足正常使用;极限状态以及承载能力极限状态各项指标满足规范要求。     

双幅T型刚构桥同步转体施工控制技术

为了确保特殊转体桥梁工程建建设活动的安全顺利开展,采用精细化数值有限元分析、现场实时监控及液压同步转体的方法,对某大型复杂T行刚构桥梁转体过程中结构整体的动态安全性进行控制,转体过程中启动、转动、制动、点动全过程及就位后桥梁应力线形及稳定性良好,达到了预期效果;文中总结和推荐的双幅T构桥梁前期监控方案及转体过程多指标实时监控技术可以很好地确保整个转体施工过程的安全性,可为同类型工程的施工提供技术参考。     

既有T形刚构桥无损检测及承载力评定

介绍了既有T形刚构桥无损检测和承载力评定的方法,其中理论值的计算用Midas进行建模分析,为使模型与实际工作情况更加接近,考虑了桩土共同作用的影响,根据评定结论提出了加固维修建议,从而确保结构的耐久性。     

T形刚构桥承台大体积混凝土温度应力分析及试验研究

介绍了大体积混凝土温度场的计算方法和有限元模拟原理,根据实际情况确定了求解的边界条件。对某桥承台大体积混凝土施工过程的温度场进行了模拟分析,同时对温度进行了监测。根据模拟分析结果和监测数据,分析了承台大体积混凝土温度及温度应力的变化特点,结合分析结果和现场情况提出合理的降温措施有效地减小承台混凝土的温差,防止了温度裂缝的出现,确保承台的施工质量。     

谈旧桥拆除的施工管理

结合具体实例,对旧桥拆除的施工管理工作进行了介绍,分别阐述了施工准备,施工方案及质量安全保证措施等内容,提出在旧桥拆除施工过程中,应加强对现场施工人员的安全教育,并建立完善的安全体系,以确保拆除工作顺利进行。     

Monitoring demolition of prestressed concrete

The experiences reviewed here include one where a bridge demolished had such great prestress loss that it was sagging under its own weight. This illustrates the changes that can occur over time and the difficulty of having accurate information available to the demolition contractor. The authors therefore emphasise the importance of monitoring prestressed concrete during demolition to provide feedback, and describe how this can be done economically. Experience shows that some prestressed concrete can be safely demolished by conventional balling or breaking methods, but control is best achieved by cutting or burning the tendons in a predetermined sequence. The authors are with the Demolition and Recycling Research Unit, University of Surrey, UK.     

Monitoring demolition of prestressed concrete

The experiences reviewed here include one where a bridge demolished had such great prestress loss that it was sagging under its own weight. This illustrates the changes that can occur over time and the difficulty of having accurate information available to the demolition contractor. The authors therefore emphasise the importance of monitoring prestressed concrete during demolition to provide feedback, and describe how this can be done economically. Experience shows that some prestressed concrete can be safely demolished by conventional balling or breaking methods, but control is best achieved by cutting or burning the tendons in a predetermined sequence. The authors are with the Demolition and Recycling Research Unit, University of Surrey, UK.     

预应力混凝土桥梁管道压浆

结合预应力混凝土桥梁预应力管道压浆质量检测的重要性,就预应力管道压浆的目的及影响因素作了论述,并针对如何保障预应力管道压浆质量问题进行了分析,同时给出了一些技术措施,以达到预期目标。     

浅谈钢筋混凝土T型梁桥的检测与加固

结合钢筋混凝土桥梁的检测、加固、维修方法及加固后的检测手段,总结对神木段两座钢筋混凝土T型梁桥检测加固过程中积累的经验,浅谈对钢筋混凝土T型梁桥进行合理加固改造的认识,使之既节约费用又能提高其承载力,满足目前交通要求。     

Spline finite strip analysis of prestressed concrete box-girder bridges

The analysis of prestressed box-girder bridges using the spline finite strip method is presented. In the present study, the spline finite strip method is modified by using the non-periodic B-spline interpolation. In the analysis of the prestressed box-girder bridges, the short-term losses of prestressing are considered and each tendon force at the tendon point is evaluated by summation of the adjacent segment forces. Once the equivalent forces acting on the structure at the tendon points are found, they are transformed into statically equivalent forces at the adjacent node of nodal line. Several examples were analyzed to verify the performance of present method. Good agreements were obtained when compared with the previous studies.     

后张法预应力混凝土桥梁施工技术

结合工程实例,从支架和模板的施工、绑扎钢筋、安置波纹管等方面,对后张法预应力混凝土桥梁施工技术进行了阐述,并总结了施工安全措施,从而确保桥梁施工质量,延长桥梁使用寿命。     

预应力混凝土梁桥病害分析研究

指出预应力混凝土梁桥是目前我国应用最为广泛的桥梁类型,但是由于服役时间的增长,结构性能下降,大量的公路桥梁产生了各种不同的病害,对预应力钢筋混凝土梁桥所常见的病害及其产生原因进行了研究总结,为研究预应力混凝土梁桥病害奠定了基础。     

后张法预应力混凝土桥梁施工质量要点

针对后张法预应力混凝土桥梁施工质量控制要点进行了介绍,重点从低松弛预应力钢绞线检验、加工、安装、张拉、压浆等施工关键技术方面进行了论述,对现场施工具有一定指导意义。     

装配式预应力混凝土箱梁桥施工方案

简要介绍了钻孔灌注桩、承台、墩柱及盖梁的施工要点,并对装配式预应力混凝土连续箱梁的预制和安装施工方案进行了论述,提出了施工注意事项,为今后类似工程施工提供了参考借鉴。