The effect of group behavior on the pull-out capacity of model soil nails in high plasticity clay

Date

2024-06-01

Author

Akis, Ebru
Bakır, Bahadır Sadık
Yılmaz, Mustafa Tolga

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

16
views

0
downloads

Cite This

Soil nailing technique is widely used in stabilizing roadway and tunnel portal cut excavations. The key parameter in the design of soil nail systems is the pull-out capacity. The pull-out capacity of soil nails can be estimated either from the studies involving similar soil conditions or from the empirical formulas available in the literature. Particularly, it has been documented placing nails closer than a certain minimum distance results in a reduction in the pull-out resistance of a nail placed in sand. However, this requirement has not been discussed for the nail groups located within clay formations. In order to investigate the influence of nail spacing on the pull-out resistance of nails, a series of laboratory pull-out experiments were performed in clay of high plasticity. The results of these experiments showed a remarkable trend. Specifically, there was a significant reduction in the pull-out capacity of a nail when the spacing between nails two times the nail diameter (2Ø). In contrast, the pull-out capacity of a nail embedded in clay remained unaffected by neighboring nails, provided the spacing was maintained at six times the nail diameter (6Ø). In addition, during the conducted pull-out tests, it was observed that the failure mode of a single nail and 6Ø spaced group nails near the surface results as heaving around the single nail. However, in the case of closely positioned (2Ø spaced) nails, the affected area following nail failure exhibits distinct characteristics, which operate as a group. This leads to the occurrence of failure in the form of heaving around the group of nails.

Subject Keywords

Nail group capacity, Pull-out capacity, Pull-out experiment, Small-scale model, Soil nailing

URI

https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85193805372&origin=inward
https://hdl.handle.net/11511/109976

Collections

Department of Civil Engineering, Article