Development of A New Prestressed Composite Slabs by Using Bottom Skin Plate as Prestressing Tendon

本研究首先介绍了作者设计的钢板和棒材双向张拉设备的概况。然后介绍了组合板的双向预应力试验结果，并与基于钢-混凝土不完全相互作用的有限元数值分析结果进行了比较。最后，根据Trost徐变方程，通过徐变试验和数值分析，明确了双向预应力叠合板的徐变行为。结果表明：(A)采用这种新的预应力技术，混凝土纵向和横向的有效预应力分别达到150~175kgf/cm~2(15~17 Mpa)和50kgf/cm~2(4.9 Mpa)。(2)有限元分析假定在这种组合板中引入的预应力可以反映钢板与混凝土之间的不完全相互作用，(3)在FukR假定双向预应力组合板的徐变行为是独立的假设下，Trost方法可以实用地估计双向预应力组合板的徐变行为。

This study, firstly, presents an outline of two-way tensioning equipment for steel plate and bars designed by the authors. Then, it discribes the result of two-way prestressing test for composite slabs, comparing with the numerical result by the finite element analysis based on incomplete interaction between steel and concrete. Finally, the creep behavior of the two-way prestressed composite slab are made clear by the creep test as well as numerical analysis on basis of the Trost's creep equation.The results obtained are : as follows :(a) By the proposed new prestressing technique, the effective prestress can be introduced in concrete by almost 150 to 175kgf/cm^2 (15 to 17MPa) in longitudinal direction and 50kgf/cm^2 (4.9MPa) in transverce direction, respectively.(b) FEM analysis assumed the incomplete interaction between steel plate and concrete can be evaluated for the introduced prestress in such a composite slab.(c) Trost's method can estimate practically the creep behavior of two-way prestressed composite slab on assumption of independent creep behavior in each direction by Fukr.