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http://dx.doi.org/10.12652/Ksce.2022.42.6.0825

Reinforcing Effect of Buildings Considering Load Distribution Characteristics of a Pre-compressed Micropile  

Lee, Kwang Hoon (The University of Suwon)
Park, Yong Chan (BTM E&C CO.,LTD.)
Moon, Sung Jin (EDOGA Consultants CO.,LTD.)
You, Kwang Ho (The University of Suwon)
Publication Information
KSCE Journal of Civil and Environmental Engineering Research / v.42, no.6, 2022 , pp. 825-836 More about this Journal
Abstract
Micropiles can be used to support additional load in extended building structures. However, their use brings about a risk of exceeding the bearing capacity of existing piles. In this study, pre-compression was applied to distribute the load of an existing building to micropiles, and an indoor loading test was performed to confirm the structural applicability of a wedge-type anchorage device designed to improve its capacity. According to the test results, the maximum strain of the anchorage device was 0.63 times that of the yield strain, and the amount of slip generated at the time of anchorage was 0.11 mm, satisfying structural standards. In addition, using MIDAS GTS, a geotechnical finite element analysis software, the effect of the size of the pre-compression, the thickness of the soil layer, and the ground conditions around the tip on the reaction force of the existing piles and micropiles were analyzed. From the numerical analysis, as the size of the pre-compression load increased, the reaction force of the existing pile decreased, resulting in a reduction rate of up to 36 %. In addition, as the soil layer increased by 5 m, the reduction rate decreased by 4 %, and when the ground condition at the tip of the micropile was weathered rock, the reduction rate increased by 14 % compared with that of weathered soil.
Keywords
Vertical extension; Micropile; Pre-compression; Load distribution;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
연도 인용수 순위
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