夹Φ20mm钢筋体复合锚杆原位锚固特性分析

Analysis of the field anchoring characteristics of composite bolts containing steel bars(20-mm diameter)

加钢筋体复合锚杆在土遗址载体锚固得到了较为成功的应用,但该类型锚杆的机理研究还是空白。为此,选择交河故城开展夹Φ20mm钢筋体复合锚杆现场锚固测试,包括锚固性能测试和锚杆各界面层应变监测。试验结果表明:1)3m长复合锚杆极限锚固力可达150kN,杆体表现出较强塑性变形。2)钢筋-复合材料界面层轴向应变远大于其他界面层,锚固失效在该层。3)由于杆体的非均直性,楠竹-复合材料界面表现出轴向应变的非规律性,局部出现受压状态。4)楠竹-浆体界面层与楠竹-复合材料界面层在较高荷载下出现剪应变向锚固末端的传递特征。5)鉴于杆体的多圈层构造,受力过程中出现明显的横向传递和剪胀特征。

Composite bolts containing steel bars have been successfully applied for the anchorage of earthen sites.However,the mechanism of anchoring has not been studied yet. In the Jiaohe ruins（ a typical earthen site）,composite bolts containing 20-mm diameter steel bars were chosen for pull-out experiments and to monitor the interface strain along the bolt. The experimental results indicate： 1） the maximum anchoring force of a 3-m long bolt is over150 k N,and the bolt shows strong plastic deformation; 2） at the damage interface,the axial strain of the interface between steel and composite material is greater than at others; 3） due to the heterogeneity of the bolt,the irregularity of the axial strain occurs at the interface between bamboo and composite materials,which creates some local compression phenomena; 4） the change of shear strain along the bamboo-grout interface and the bamboo-composite material interface coincides with that of the pull-out load,and shear strain is transferred to the end of the bolt under higher loads; 5） because of the multilayer structure of the bolt,transverse transfer and shearing expansion appear distinctly during the pull-out experiment.