Abstract：To study the effects of grout defects on the seismic performance of pre-cast assembled concrete columns with longitudinal reinforcement spliced by grout sleeves, quasi-static tests of 4 assembled columns specimens with shear span ratio of 5 and axial compression ratio of 0.3 were performed. Specimen BM-01 was fully connected with no defects, while the anchorage lengths between 1 to 3 reinforcements and grouting material for specimens QX-01~03 were reduced by 50%to simulate the grouting defects (A column specimen had 8 longitudinal reinforcements). The test indicated that the grout-bar bond of specimen BM-01 was good. The hysteretic curve of load-displacement showed perfect symmetry and full shape with good seismic performance. The damage of specimens with grouting defects was localized to the columns base with a major horizontal crack opening at the grout layer beneath the sleeves, caused by longitudinal reinforcement slippage. The hysteretic curve of load-displacements of QX-01-03 specimen showed good asymmetry and pinching effect. It is the grouting defects that lowered the bearing capacity and ductility performance. The peak load and the ultimate load in negative direction of specimens with defects were just about 70% to 90% of that for specimen BM-01. The ductility coefficient for specimen QX-03, which had the most grouting defects, was only 58% of that for specimen BM-01. Compared to specimen BM-01, the stiffness and the energy dissipation capacity of specimens with grouting defects showed increasing degradation with the horizontal displacement, and they were just respectively 70% to 90% and 75% to 95% of that for specimen BM-01 when the drift ratio were 1/50.
郑清林 王霓 陶里 田欣. 套筒灌浆缺陷对装配式混凝土柱抗震性能影响的试验研究[J]. 土木工程学报, 2018, 51(5): 75-83.
Zheng Qinglin Wang Ni Tao Li Tian Xin. Experimental study on effects of grout defects on seismic performance of assembled concrete columns. 土木工程学报, 2018, 51(5): 75-83.
