Experimental Research On Bearing Behavior Of Underreamed Uplift Anchor

Innovation of form in anchor is a tendency. Expanded anchor is one of new forms, which is topic of this paper. Expanded anchor is a method that enlarges diameter of bottom half of anchor, in the course of anchor construction. Expanded anchor has larger value of capacity, result from the enlarged section。It’s necessary to research the loading mechanism different from the normal anchor.Loading mechanism and calculation of capacity are researched in this paper through pull-out test andABAQUS. Follows are results:(1) The loading capacity of normal anchor is 400 kN compared with another five expanded anchors of different diameters have the capacity of 800 kN,900 kN,1000 kN in the same site pull-out test.(2) Diameter of expanded anchor has large influence to capacity. The capacity grow rapidly with the grow of diameter. Diameter of expanded anchor is better between Twice and triple of normal anchor.(3) Length of expanded part has little influence to the capacity. One third of whole length of anchor is better to adapted as the expanded.(4) ThroughABAQUS, axial force decreases rapidly at the surface of variable cross-section, which means capacity of expanded anchor is beard by the expanded part. In the results ofABAQUS, same issues are got with site pull-out test that diameter has larger influence as to length of expanded part.Capacity of expanded anchor becomes larger as with the increase of c and Ф,results fromABAQUS.Pull-out test is done in a project of urban village in city regeneration, which can be mirrored to similar projects.