Research on the Application of Newly Developed Prestressed Concrete Structures

考虑到在桥梁中的应用，对新开发的PC结构的实际应用进行了研究。将超高强纤维混凝土(UFC)应用于PC梁腹板部分，以获得强度高、耐久性好的优良组合结构。从2003年的基础研究中发现，剪力键的应用和钢筋的穿透是有效的，并证实了PC梁边缘的短桩对止滑也是非常有效的。2004年，在2003年所获知识的基础上制作了PC梁试件。实际上，2004年已经研究了各种形状的腹板构件，如矩形墙板、三角形墙板、桁架构件或预应力桁架构件。通过试验和非线性有限元数值分析，对UFC腹杆的刚度、变形能力和极限承载力进行了验证，结果表明，新研制的UFC腹杆PC结构具有良好的受力性能。特别是，当使用矩形面板时，三角形面板或桁架构件的承载力增加了一倍以上。综上所述，新型PC结构，即以UFC构件为腹板的PC梁，可以创造出安全可靠的土木工程结构。这项研究的成果发表在《材料、混凝土结构与路面杂志》、《日本混凝土学会会刊》等多个期刊上。

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.