| Title |
Control of Horizontal Drainage Layer Deformation through Field Test in Deep Soft Ground Improvement |
| Authors |
박태광(Park, Tae-Kwang) ; 박주영(Park, Joo-Young) ; 강승찬(Kang, Seung-Chan) ; 김태형(Kim, Tae-Hyung) |
| DOI |
https://doi.org/10.12652/Ksce.2025.45.2.0237 |
| Keywords |
수평배수층; 성토; 연약지반; 급속 침하 및 융기; 성토속도 Horizontal drainage layer; Embankment fill; Soft ground; Rapid settlement and heaving; Fill rate |
| Abstract |
Recently, maintenance costs are increasing in Busan New Port due to residual settlement exceeding the allowable settlement. As of 2022, most of the residual settlement in New Port through leveling exceeded the allowable settlement. In the case of container pier 5, a settlement of 47.5 cm occurred, which greatly exceeded the allowable settlement of 10 cm. The residual settlement problem is closely related to the functional deterioration due to the deformation in the cross-section of the horizontal drainage layer. In this study, thus, the deformation of the horizontal drainage layer due to ground improvement was examined using existing measured data and confirmed by measuring surface settlement, pore water pressure, groundwater levels, and multi-layer settlement in field test. As a result of analyzing the measurement data for each section of the Busan New Port, it was found that the tendency for settlement and heaving was significant in the early stage of embankment fill (height of 0 to 4.0 m). Field test measurements showed that if embankment management is properly performed (a one-time fill of 0.5 m, rate of 3.3 cm/day), the deformation of the horizontal drainage layer can be sufficiently controlled when the separation distance between water collection wells is 60 m, ensuring no issues with its function. In other words, there was no rapid settlement or heaving of the horizontal drainage layer due to the fill, and the cross-section of the horizontal drainage layer remained intact. The measurement results confirmed that proper initial embankment management prevents cross-sectional deformation that would impair the horizontal drainage layer. |