CFRP网格加固受损盾构隧道模型试验研究

摘要

The effectiveness of carbon fiber reinforced polymer(CFRP)grids as the strengthening materials for a pre-damaged scaled tunnel model is experimentally investigated.First,the bond performances between the CFRP grid and the concrete under different types of adhesive and surface treatment were tested.The most efficient anchoring system was adopted for the subsequent scaled tunnel strengthening.Test results show that when the epoxy structural adhesive was used as the bonding material,the failure mode was CFRP grids rupturing,and the anchorage performance was optimal.When the polymer mortar was used as the adhesive,the surface treatments with anchored bolts and grooves can improve the bond performance,and the failure mode was sliding failure with the polymer mortar peeled off.After strengthening with CFRP grids,both the stiffness and the load capacity of the pre-damaged scaled tunnel model were improved.Additionally,%对碳纤维增强树脂(CFRP)网格加固受损缩尺盾构隧道模型的有效性进行了试验研究.首先,对CFRP网格与混凝土表面采用不同粘结材料和表面处理方式时的粘结性能进行了研究.采用最有效的锚固方式对随后的缩尺隧道进行了加固.研究结果表明,采用环氧结构胶作为粘结材料时,粘结试验均表现为网格材料破坏,粘结锚固性能最优;而采用聚合物砂浆锚固时,表面锚栓锚固处理和表面开槽处理均能提高粘结性能,破坏模式为聚合物砂浆剥落的滑移破坏.受损隧道模型采用CFRP网格加固后,刚度和承载力都得到了明显提升.此外,FBG的测试结果表明,加固后的隧道环缝应变减小,隧道整体性能得到提升.