先张法折线预应力技术在桥梁工程中的应用研究

Research on the Application of Prestressing Technology with Pretensioned Draped Strands in Bridge Engineering

先张法预应力技术具有施工工序简单、材料节省、质量可靠等优点,先张法折线预应力使梁的受力和预应力用量更加合理,并能适应更大的跨径。先张法折线预应力桥梁构件在国外应用较为广泛,在国内随着工业化建造水平不断提高也日益受到重视,多个省市开展了技术研究和工程应用。预应力弯折是先张法折线预应力构件的重要工艺环节,介绍了常用预应力弯起方式和弯起器构造。研发了一种新型预应力弯折工艺和配套的分体组合式下压锚具,具有操作简便、标准化程度高、节省材料等特点。

Pretensioned prestressing technology has the advantages of simplitied construction process,saving in materials,reliable quality,etc.The use of pretensioned draped strands results in more reasonable structure and strands consumption and larger spans of prestressed girders.Prestressed girders with pretensioned draped strands have been widely used in foreign countries and are paid more and more attention in China with the development of industrialized construction.Research and application of this technology have been implemented in some provinces.Draping of strands is an important step of the fabricating process.Common draping methods and strands restraining devices were introduced in this paper.A new type of draping method and corresponding split-combined depressors were developed.which had the features including easy operation*high degree of standardization and saving in materials.