Reactive powder concrete-filled steel tube (RPCFT) consists of rectangular or circular steel tube filled with reactive powder concrete (RPC). Currently, there is a general lack of knowledge regarding the behavior of RPCFT members subjected to axial tension. This paper addresses the knowledge gap by conducting experimental tests on 57 specimens, including 33 RPCFT specimens, 21 RPC specimens, and three hollow steel tube (HSS) specimens. The test parameters are the diameter-to-thickness ratio of the steel tube, fiber reinforcement ratio, and curing temperature. The test results indicate that the tensile strength of RPCFT members increases with increasing fiber reinforcement ratios and curing temperatures or with decreasing diameter-to-thickness ratios of the steel tube. As compared to conventional concrete-filled steel tube (CFT) members, RPCFT members have: (i) a similar tensile behavior, i.e., the steel tube has an increased tensile strength and does not have any pinching due to the interaction between the steel tube and concrete infill; and (ii) a higher tensile strength because RPC with fibers has a higher tensile strength than conventional concrete and can maintain its tensile capacity at large strains. This paper also evaluates the applicability of current design equations for estimating the axial tensile strength of RPCFT members. The evaluation indicates that the current design equations are over-conservative for RPCFT members. This paper then proposes a new design equation for estimating the axial tensile strength of RPCFT members. The accuracy of the proposed equation is confirmed by using it to predict the strength of the 33 RPCFT specimens tested in this research.

活性粉末混凝土填充钢管（RPCFT）由填充有活性粉末混凝土（RPC）的矩形或圆形钢管组成。当前，关于RPCFT构件承受轴向拉力的行为普遍缺乏知识。本文通过对57个标本进行实验测试来解决知识差距，其中包括33个RPCFT标本，21个RPC标本和三个中空钢管（HSS）标本。测试参数是钢管的直径/厚度比，纤维增强比和固化温度。测试结果表明，RPCFT构件的抗拉强度随着纤维增强比和固化温度的增加或钢管直径/厚度比的降低而增加。与传统的钢管混凝土构件相比，RPCFT构件具有：（i）类似的抗拉性能，即钢管具有增强的抗拉强度，并且由于钢管和混凝土填充物之间的相互作用而没有任何夹伤；（ii）较高的抗拉强度，因为含纤维的RPC具有比常规混凝土更高的抗拉强度，并且可以在大应变下保持其抗拉能力。本文还评估了当前设计方程用于估算RPCFT构件的轴向拉伸强度的适用性。评估表明，当前的设计方程对于RPCFT成员而言过于保守。然后，本文提出了一个新的设计方程式，用于估算RPCFT构件的轴向拉伸强度。通过使用该方程预测本研究中测试的33个RPCFT标本的强度，可以证实该方程的准确性。