Research on the Application of Newly Developed Prestressed Concrete Structures

考虑到桥梁的应用，新开发的PC结构的实际使用进行了研究。将超高强度纤维混凝土（UFC）用于PC梁腹板，以实现具有高强度和高耐久性的优异组合结构。根据2003年进行的基础研究，剪切键的应用和钢筋的渗透被发现是有效的，并且确认PC梁边缘的短柱也非常有效地阻止滑移。2004年，根据2003年获得的知识制作了PC梁试件。实际上，在2004年对各种形状的腹杆进行了研究，例如矩形板、三角形板、桁架杆件或预应力桁架杆件。通过试验和非线性有限元数值分析，验证了UFC作为腹杆的新型PC结构的刚度、变形能力和极限承载力，表明其具有良好的受力性能。特别是，当矩形面板被使用时，对于三角形面板或桁架构件的情况，承载力是两倍以上。桁架构件的预应力效果也非常有效。总之，新开发的PC结构，即，以UFC构件为腹板的PC梁被证实可以创造安全可靠的土木工程结构。本研究的结果发表在JSCE的《材料、混凝土结构与路面杂志》、《日本混凝土研究所学报》等杂志上。

Giving a mind to the application to bridges, the practical use of newly developed PC structures has been investigated. The ultra-high strength fiber reinforced concrete (UFC) was used to the web part of PC girders to achieve the excellent composite structures having high strength and durability. From the basic research done in 2003, the application of the shear key and the penetration of reinforcing bars were found to be effective and it was confirmed that the stub at the edge of a PC girder was also very effective to stop the slip. In 2004, the specimens of PC girders were produced based on the obtained knowledge in 2003. Actually, various shapes of web members were examined in 2004, such as rectangular panels, triangular panels, truss members or truss members with prestress. By experiments and numerical analyses using nonlinear FEM, the stiffness, deformation ability and ultimate capacity were verified.According to these examination, the newly developed PC structures using UFC as web members have indicated the excellent mechanical behavior. Especially, when rectangular panels were used, the capacity was more than double for the case of triangular panels or truss members. The effect of prestressing for truss members was also very effective.In conclusion, the newly developed PC structures, i.e., PC girders having UFC members as web, were confirmed to create safe and sound civil engineering structures. The obtained results of this research were presented in various journals, such as Journal of Material, Concrete Structures and Pavement of JSCE, and the Proceeding of Japan Concrete Institutes.