通过对内贴应变片钢筋的拉拔试验,对比分析了不同轻骨料体积分数和水灰比条件下,次轻混凝土与光圆钢筋的黏结滑移特点以及黏结应力及应变沿锚固长度的变化规律。研究结果表明:随着轻骨料体积分数及水灰比的增大,次轻混凝土与钢筋的极限黏结强度降低,相应的滑移增大;相同混凝土强度等级条件下,次轻混凝土黏结强度高于普通混凝土的黏结强度;最后给出了光圆钢筋极限黏结强度与混凝土抗拉强度的回归公式。
The effect of volume fraction of light aggregate and water-cement ratio on the bonding performance between plain round bar and specified density concrete are analyzed by the pull-out test.In the test, the bond-slip characteristics and the change law of steel bond stress along the anchor position are discussed.The results show that with the increasing of volume fraction of light aggregate and water-cement ratio of concrete,the ultimate bond strength decreased, and the corresponding slip increases.With the same concrete strength grade, bond strength of the specified density concrete is higher than the normal concrete.The calculating formula for the relationship between ultimate bond strength of plain round bar and tensile strength of concrete is given.