Abstract

The performance of a double-core prefabricated vertical drain (PVD), which could reduce the well resistance via its large cross-sectional area and structural stability, was investigated experimentally and numerically. The double-core and the conventional single-core PVD, which has been widely adopted in reclaimed ground improvement, were compared in this study. In the experimental investigation, modified Delft tests and a calibration chamber test were carried out in a laboratory to determine the discharge capacities of the PVDs. Thereafter, single- and double-core PVDs were installed in the Busan New Port site, which had a 40 m thickness of clay deposit, and the performances of the PVDs estimated through surface settlements were compared. In addition, a numerical program named ILLICON was applied with field measurements, and a parametric study was conducted for different discharge capacities of the PVDs. The result of the laboratory tests and field measurements indicated that there was no difference in the performance between the two types of PVDs for improving the soft ground, considering actual ground conditions. Similarly, the parametric study results also implied that both PVDs could be satisfactorily applied in thick reclaimed ground, and there is no significant difference in the performance of single- and double-core PVDs.

摘要

采用实验和数值方法研究了双芯预制垂直排水管 (PVD) 的性能，它可以通过其大横截面积和结构稳定性来降低井阻。本研究比较了已广泛应用于填海地基改良的双核和常规单核 PVD。在实验研究中，在实验室中进行了改进的代尔夫特测试和校准室测试，以确定 PVD ​​的放电容量。此后，在具有 40 m 厚粘土沉积物的釜山新港现场安装了单芯和双芯 PVD，并比较了通过地表沉降估计的 PVD ​​的性能。此外，一个名为ILLICON的数值程序应用现场测量，并对PVD的不同放电容量进行了参数研究。实验室测试和现场测量结果表明，考虑到实际地基条件，两种 PVD ​​对软土地基的改善性能没有差异。同样，参数研究结果也表明两种 PVD ​​都可以令人满意地应用于厚实的填海地基，并且单芯和双芯 PVD ​​的性能没有显着差异。