| 要旨 |
An experimental investigation was carried out in order to predict the bond behavior of a newly developed lapping joint for Precast Concrete (PCa) Columns. Pull out test on 27 specimens was carried out. Each one of the specimens represented the confined section of PCa columns, where steel sheaths were placed at the main bar positions and lapped with two bars each, and then, the main bars were inserted from the both sides of the sheath, so each main bar abutted at the middle height of the column specimens and high strength mortar was grouted inside. The influences of the following parameters were studied: loading history, diameter of main bars, lapping bar length, and concrete strength. The test results showed a good performance for developing the full strengths of main bars D25 (SD390) for concrete strength Fc = 400 kgf/cm2 and D22 (SD390) for Fc = 300 kgf/cm2, under the condition that the lapped length of 30 times the diameter of the lapping bars was used. |