关键词: 楠竹加筋复合锚杆, 土遗址, 黏结滑移, 模型

Abstract:

The bamboo-steel cable composite anchor (BSCC anchor) is a new anchor with phyllostachys heterocyclavar as pipe material, and was applied to reinforce earthen ruins bequeathed on the ancient silk road in Northwest China, which can get high anchorage strength due to its big cross-section. Field test illustrated that the failure of BSCC anchor was characterized by pulling-out of steel strand from inner binder .In order to understand the working mechanism between inner binder and steel strand, laboratory tests were conducted on four species of specimens, to investigate the bond-slip property between them. The test results indicate that there are three stages for the bond-slip process between inner binder and steel strand which are exponential-enhancing stage, softening-declining stage and residual stress stage. Moreover, the length of softening-declining stage is short, and the bond-slip process can be described by a simplified model and an exact model. It is found that the shear stress is not uniform distributing between the interface of inner binder and steel strand; and it approaches a peak near the loading end; and the peak stress increases and shifts far further from the loading end when pulling load is increased. The average shear stress between inner binder and steel strand, submits exponential decay regularity, and decreases along with the anchor length during the bond-slip process. It acquires the differential equation of bond-slip through theory analysis ,and the variation rules of the axial force of steel strand and relative displacement between the interface of inner binder and steel strand. From results, it is found that the axial force of steel strand and relative displacement decrease along with the anchor length; and the results can be used for anchor design and application.

Key words: bamboo-steel cable composite anchor (BSCC) anchor, earthen ruins, bond-slip, model