|主題||The Dowel Action of Steel Bars in the Joint Connection of Precast Reinforced Concrete|
|筆頭著者||Shuang Xie（Kanto Gakuin University）|
|連名者1||Eiji Makitani（Kanto Gakuin University）|
|連名者2||Shouhei Ogawa（Daiwa House Industry Co. LTD.）|
For the connection of precast reinforced concrete which is located at beam-column interface, the shear transfer of steel bars across the connection face is researched on the basis of the dowel action of steel bars. This dowel action idealizes the flexural ridigity of steel bars and spring constant coefficient of concrete under the bars as elastic support model. Its behaviour is not only influenced by the flexural rigidity and spring constant coefficient, but is also influenced greatly by joint connection.
The object of this study is to investigate the behaviour of the dowel action. Two blocks of precast reinforced concrete members are connected by steel bars and joint connection as a test specimen. The relationship between dowel action feature and connection width is investigated on the basis of the theory of elastic support model. Especially. in order to solve the resistance mechanism of dowel action, the relation among the distance from connection face to the point of maximum bending moment, connection width and steel bar diameter is chiefly analysed. The results of test and analytical studies are described as follows.
Based on the beam theory on an elastic foundation. tests are performed on specimens simulating the dowel action of steel bars at the precast reinforced concrete beam-column interfaces. The following conclusions are obtained.
1)When steel bars transfer shear force from one concrete member to the another. the compressive stress mainly distributes in the area where is from the connection face (x=0) to the position of maximum bending moment of steel bars (x=a) and its value is the function of the deflection v of steel bars.
2)From the tests, the relative stiffness β of precast reinforced concrete is inversely proportional to the diameter of dowel steel bars.
3)When the width of connection Lj < 2.37/β, the distance a of the maximum bending moment from the face of connection is calculated by equation ; otherwise, a is calculated by equation.
4)The model in which the dowel steel bar is idealized as a beam on an elastic foundation successfully predicts due experimental test values.
5)The location of the maximum bending moment of dowel steel bars which is aslo the location of plastic hinge is the basic materials for the analysis of shear transfer behaviour of dowel steel bars in the joint connection of precast reinforced concrete.