济南某工程大跨度预应力结构有关问题的探讨

介绍了济南某工程大跨度预应力结构的测试分析方法,用ANSYS有限元程序对这种带次框架的大跨度预应力结构的受力特点进行分析,在张拉顺序、预应力梁截面改变对内力的影响、预应力施加后对结构的影响以及次弯矩的作用等方面进行了探讨并给出自己的结论,针对设计和施工提出建议。     

Application of shape memory alloy bars in self-centring precast segmental columns as seismic resistance

The objective of this study is to investigate analytically the performance of self-centring precast segmental bridge columns with shape memory alloy (SMA) starter bars under nonlinear static and lateral seismic loading. For this purpose, a 3D finite element model for hybrid post-tensioned bridge column has been developed. The precast post-tensioned segmental bridge columns possessing a central tendon and adequate transverse confinement provided by the steel tube jacketing as self-centring bridge columns have an undesirable high lateral seismic demand due to their low energy dissipation. In order to eliminate this deficiency while keeping the residual displacement small, SMA starter bars are applied in this system. The effect of post-tensioning (PT) forces of the central strands and SMA bar size are investigated. The results indicate that in high seismicity zones, bridge columns with SMA bars at a higher level of PT forces have a superior performance against earthquake loading.     

谈预制预应力空心桥板的施工监理质量控制

论述了预应力钢筋混凝土预制空心桥板支模、拆模和钢筋、预应力钢绞线等监理工作要点，以利于提高监理工作质量。     

后张法有黏结与无黏结预应力混凝土施工比较

后张法有黏结与无黏结预应力混凝土工程的施工,既有相同之处,也有一定的差别。通过施工工艺流程、预应力筋的铺设、预应力张拉和孔道灌浆,可以看出两种后张法预应力混凝土工程的差异。最后总结了施工管理的要求。     

真空辅助压浆技术在高架桥梁施工中的应用

以苏州工业园区北环东延三标高架桥工程为例,介绍了真空辅助压浆的基本原理及优点,阐述了真空辅助压浆的施工工艺流程、注意事项,实践证明该方法能有效确保孔道压浆质量,提高结构的安全性及耐久性,减少安全隐患。     

Beam strengthening by external post-tensioning: Design recommendations

Buildings and bridge structures are often in need of strengthening due to deterioration of material properties or a change in design loads. External post-tensioning, in which tendons are installed on the outside of a structural member with the aid of deviators and anchorages, is an attractive strengthening method as it does not add much weight and can be carried out with minimal disruption to the operational function of the structure. An extensive programme has been carried out on simple-span and continuous beams as well as beams in reinforced concrete frames to study the effect of tendon configuration, second-order effects, and secondary and tertiary effects due to external post-tensioning. The effect of external post-tensioning on shear capacity and the use of fibre-reinforced polymer prestressing cables were also examined. This paper highlights the main findings of the study, based on which design recommendations are given and a direct design approach is proposed.     

某厂房27m跨后张预应力屋架施工质量监控

在某排架结构的工业厂房中,27m跨后张预应力屋架的制作、吊装是重要的分项工程。文章研究采用后张法现场制作27m预应力钢筋混凝土屋架的施工质量监控,实践证明,为保证工程质量而采用严谨的施工方案、完善的质量保证体系和安全措施,并且严把每道工序关,就可以使屋架施工达到设计要求。     

混凝土空心板预应力筋张拉的质量控制

预应力混凝土空心板后张法施工得到了广泛的应用,作者结合工程实例,着重介绍预应力钢绞线张拉伸长量的计算方法,以及后张法预应力张拉的控制措施。     

分析后张法在预应力T梁施工中的质量控制

随着我国桥梁技术的不断发展,在预应力T梁进行施工的过程中,后张法是其中不可缺少的一项技术。在本文中,就后张法在预应力 T 梁施工中的质量控制进行了分析与探讨。     

后张法预应力筋张拉控制方法

以16m预应力梁板后张法施工为例,探讨了后张法预应力筋在施工中如何进行张拉控制,分别介绍了张拉工艺流程,机具设备的选择,伸长值的理论计算,实际伸长值的测量等内容,为今后后张法预应力张拉施工提供了经验。