关键词: 扩大头锚杆, 抗拔承载力, 原位试验, 数值模拟, 承载特性

Abstract: Expanded-head anchors, owing to their distinctive geometry and load-transfer mechanism, are widely employed in applications such as basement uplift resistance. Based on an actual foundation-pit project in Hefei, a numerical model of the expanded-head anchor-soil interaction was established using the ABAQUS finite-element platform to investigate the uplift bearing behavior under different loading levels. Comparison between field pullout tests and numerical simulations confirmed the validity of the finite-element model through consistent load-displacement responses. Field test results indicate that the deformation evolution of expanded-head anchors under uplift loading comprises an elastic stage, a transitional stage, and a plastic compression-failure stage. Numerical analyses further show that the uplift capacity is governed primarily by the end-bearing resistance mobilized in the soil ahead of the expanded head, resulting in significantly higher pullout resistance compared with conventional anchors. Understanding the load-transfer mechanism and failure modes of expanded-head anchors provides important guidance for the advancement of underground engineering design and practice. 

Key words: Expanded Head Anchor, Uplift Bearing Capacity, In Situ Test, Numerical Simulation, Bearing Behavior