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http://dx.doi.org/10.7843/kgs.2021.37.2.19

3-D Numerical Analysis for the Verification of Bearing Mechanism and Bearing Capacity Enhancement Effect on the Base Expansion Micropile  

Lee, Seokhyung (Dept. of Infrastructure Safety Research, Korea Inst. of Civil Eng. and Building Tech.)
Han, Jin-Tae (Dept. of Infrastructure Safety Research, Korea Inst. of Civil Eng. and Building Tech.)
Jin, Hyun-Sik (Hydraulic and Geotechnical Consultants)
Kim, Seok-Jung (Dept. of Infrastructure Safety Research, Korea Inst. of Civil Eng. and Building Tech.)
Publication Information
Journal of the Korean Geotechnical Society / v.37, no.2, 2021 , pp. 19-31 More about this Journal
Abstract
Micropiles are cast-in-place piles with small diameters. The advantage of micropile is low construction expense and simple procedures, so it is widely applied to existing buildings and structures for the reinforcement of foundation and seismic performances. The base expansion structure has been developed following the original mechanism of horizontal expansion steps under compressive loading. This kind of structure can be installed at the pile end to improve the bearing capacity by tip area enlargement and horizontal force increment to the pile surface area. However, 'Micropile with base expansion structure' cannot be put into practical use, because detailed verification for the developed technique has not been conducted so far. In this research, 3-D numerical analysis was conducted to figure out the bearing mechanism of base expansion micropile and to verify the bearing capacity improvement compared to the general micropiles. 3-D modelling of micropile with base expansion structure was carried out and input parameter was determined. Bearing mechanism induced by base expansion structure was analyzed by lab-scale modelling, and bearing capacity improvement was verified by field-scale analysis.
Keywords
Base expansion; Foundation reinforcement; Micropile; Numerical analysis; Seismic design;
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