Monotonic uplift behavior of anchored pier foundations in soil overlying rock

• Published in: Journal of Zhejiang University. A. Science Vol. 24; no. 7; pp. 569 - 583
• Main Authors: Sun, Yizhou, Sun, Honglei, Tang, Chong, Cai, Yuanqiang, Pan, Feng
• Format: Journal Article
• Language: English
• Published: Hangzhou Zhejiang University Press 01.07.2023; Springer Nature B.V; College of Civil Engineering and Architecture,Zhejiang University,Hangzhou 310058,China%College of Civil Engineering,Zhejiang University of Technology,Hangzhou 310014,China%State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China%Zhejiang Electric Power Design Institute Co.Ltd.,China Energy Engineering Group,Hangzhou 310012,China
• Subjects: Axial forces; Bearing capacity; Civil Engineering; Classical and Continuum Physics; Embedded foundations; Engineering; Failure mechanisms; Force distribution; Industrial Chemistry/Chemical Engineering; Limit states; Load distribution; Load transfer; Mechanical Engineering; Modulus of deformation; Mountain regions; Mountainous areas; Mountains; Piers; Pull out tests; Research Article; Rocks; Soil layers; Uplift; Uplift resistance; Anchored pier foundation; 扩底墩; 岩石锚杆; 上拔承载发挥系数; Rock anchor; Belled pier; 锚墩基础; Uplift capacity; Uplift mobilization coefficient (UMC); 抗拔承载力; Uplift mobilization coefficient(UMC)
• DOI: 10.1631/jzus.A2200446
• ISSN: 1673-565X

Rock-embedded foundations with good uplift and bearing capacity are often used in mountains or hilly areas. However, there are soil layers with a certain thickness on the rocks in these mountainous areas, and the utilization of those soil layers is a problem worthy of attention in foundation construction. Considering construction- and cost-related factors, traditional single-form foundations built on such sites often cannot provide sufficient resistance against uplift. Therefore, an anchored pier foundation composed of anchors and belled piers, specifically constructed for such conditions, can be invaluable in practice. This paper introduces an experimental and analytical study to investigate the uplift capacity and the uplift mobilization coefficients (UMCs) of the anchored pier foundation. In this study, three in-situ monotonic pullout tests were carried out to analyze the load–displacement characteristics, axial force distribution, load transfer mechanism, and failure mechanism. A hyperbolic model is used to fit the load–displacement curves and to reveal the asynchrony of the ultimate limit states (ULSs) of the anchor group and the belled pier. Based on the results, the uplift capacity can be calculated by the UMCs and the anchor group and pier uplift capacities. Finally, combined with the estimation of the deformation modulus of the soil and rock, the verification calculation of the uplift capacity and UMC was carried out on the test results from different anchored pier foundations.