Centrifuge Model Tests on Characteristics in Forced Replacement Method for Soft Ocean Ground to Build Coastal Structures

J. Ocean Eng. Technol. 2006;20(5):42-48.

Park, Byung-Soo;

G-1 Tech Co. Ltd.;

해안구조물 축조를 위한 해양연약지반의 강제치환 특성에 관한 원심모형실험

박병수;

(주)지완테크 지반공학부;

Keywords: Forced replacement method, Centrifuge model test, Dredged and reclaimed ground, Depth of replacement

핵심용어: 강제치환공법, 원심모형실험, 준설매립지반, 치환깊이

Abstract

This paper shows theresults of centrifuge model experiments to investigate the behavior of a replacement method in dredged and reclaimed ground. For this experimental work, centrifuge model tests were carried out to investigate the behavior of a replacement method in soft clay ground. Basic soil property tests were performed to find the mechanical properties of clay soil sampled from the southern coast of Korea, which was used for the ground material in the centrifuge model tests. The reconstituted clay ground of the model was prepared by applying reconsolidntion pressure in a 1 g condition with a specially built model container. Centrifuge model tests were carried out under the artificially accelerated gravitational level of 50 g. Replacement material of lead with a certain degree of angularity was used and placed until the settlement of the replacement material embankment reached a state of equilibrium. Vertical displacement of the replacement material was monitored during tests. The depth and shape of the replacement, especially the slope of the penetrated material and the water content of the clay ground were measured after finishing tests. Model tests for investigating the stability of an embankment after backfilling were also performed to simulate the behavior of a dike treated with replacement and backfilled with sandy material. As a result of the centrifuge model test, the behavior of the replacement, the mechanism of the replacement material being penetrated into clay ground, and the depth of the replacement were evaluated.