预应力高强钢绞线网-聚合物砂浆加固剪力墙抗震性能试验研究

Experimental investigation on seismic behavior of shear wall retrofitted with pre-stressed steel wire mesh and polymer mortar

通过对9片预应力高强钢绞线网-聚合物砂浆加固的钢筋混凝土剪力墙和1片未加固对比墙试件进行低周往复加载试验,研究了轴压比、单双面加固、预应力水平对抗震加固效果的影响。试验结果表明:经预应力高强钢绞线网-聚合物砂浆技术加固后,较未加固试件,剪力墙试件的开裂荷载提高83%、屈服荷载提高100%、极限荷载提高9.5%;双面加固试件的滞回性能要优于单面加固试件;在轴压比n=0.4下,较未加固试件,单面加固试件的延性最大增幅为27.7%,耗能能力最大增幅为66.07%;双面加固试件的延性最大增幅为72.8%,耗能能力最大增幅为96.60%。此外,加固后试件的刚度显著提高,刚度退化减缓;预应力水平的提高对试件的耗能能力和刚度退化影响不大,但对延性的影响较明显。

Based on the low-cycle loading tests of 9 reinforced concrete （RC） shear walls strengthened with prestressed high strength steel wire mesh-polymer mortar （PSWM-PM） and one contrast shear wall, the seismic strengthening effects of main test parameters, including axial compressive ratio, single-sided or double-sided reinforcement, prestressing level of steel wire were studied. The test results show that the cracking load, yield load, ultimate load of shear wall specimens are increased by 83% , 100% , and 9.5% ＇after strengthened with PSWM-PM. Hysteretic performance of double-sided reinforcement is better than that of the single-sided reinforcement. Through single-sided reinforcement, the maximum increase of the ductility of specimen is 27.7% and the maximum increase in energy dissipation capacity is 66.07% ; Through double-sided reinforcement, the maximum increase of the ductility of specimen is 72.8% and the maximum increase in energy dissipation capacity is 96.60%. In addition, the stiffness of the strengthened specimens is significantly increased and the stiffness degradation mitigated. The energy dissipation capacity and stiffness degradation do not change with increasing of prestressing level, but it has an obvious influence on the ductility.