Recycled lump concrete (RLC) made with demolished concrete lumps (DCLs) and fresh concrete (FC) provides a solution for effective waste concrete recycling. To promote the development of precast RLC structures, this study tested a new type of connection for precast concrete columns: connecting the upper and the lower halves of columns with bent longitudinal reinforcements and structural adhesive. In this work the behavior of precast RLC columns with the new connection was studied under axial compression. The axial compressive strength of nine two-part columns was tested. The effects of the degree of bending in the longitudinal reinforcement, the replacement ratio of DCLs and the stirrup spacing were investigated. Tests showed that: (1) the failure mode of precast concrete columns is different from that of cast-in-place columns; (2) when the strength of the waste concrete is close to that of the fresh material, there is no significant difference in the axial compression performance of either precast or cast-in-place columns; (3) the bent longitudinal reinforcement causes the axial load bearing capacity of precast concrete columns to be 4.2%–12.3% lower than that of a similar cast-in-place column; (4) reducing the stirrup spacing has little effect on a precast column’s axial load bearing capacity and ductility; (5) when using Chinese and American codes to predict the axial load bearing capacity of the column, the predicted value should be multiplied by a reduction factor.

用已拆除的混凝土块（DCL）和新鲜混凝土（FC）制成的再生块状混凝土（RLC）为有效的废弃混凝土再生提供了解决方案。为了促进预制RLC结构的发展，本研究测试了一种用于预制混凝土柱的新型连接方式：使用弯曲的纵向钢筋和结构粘合剂连接柱的上半部和下半部。在这项工作中，在轴向压缩下研究了具有新连接的RLC预制柱的性能。测试了九个两部分式圆柱的轴向抗压强度。研究了纵向钢筋弯曲程度，DCL的置换率和箍筋间距的影响。试验表明：（1）预制混凝土柱的破坏模式与现浇柱的破坏模式不同；（2）当废混凝土的强度接近于新鲜材料的强度时，预制柱或现浇柱的轴向压缩性能无明显差异；（3）弯曲的纵向钢筋使预制混凝土柱的轴向承载能力比类似的现浇柱低4.2％–12.3％；（4）减小箍筋间距对预制柱的轴向承载能力和延展性影响很小；（5）当使用中文和美国规范来预测圆柱的轴向承载能力时，预测值应乘以减小因子。（3）弯曲的纵向钢筋使预制混凝土柱的轴向承载能力比类似的现浇柱低4.2％–12.3％；（4）减小箍筋间距对预制柱的轴向承载能力和延展性影响很小；（5）当使用中文和美国规范来预测圆柱的轴向承载能力时，预测值应乘以减小因子。（3）弯曲的纵向钢筋使预制混凝土柱的轴向承载能力比类似的现浇柱低4.2％–12.3％；（4）减小箍筋间距对预制柱的轴向承载能力和延展性影响很小；（5）当使用中文和美国规范来预测圆柱的轴向承载能力时，预测值应乘以减小因子。