• Proceedings of the Korean Geotechical Society Conference
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• 2001.10a
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• pp.65-94
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• 2001

The use of PBD(prefabricated band drain)far ground improvement is rapidly increased due to the merit of construction period and cost, environmental preservation compared with other vertical drain method, and the development of material. This paper presents the historical review, theoretical background, design procedure and method, and typical construction example for the PBD. Also, the direction of further technical development and study is recommended.

• Journal of the Korean Geotechnical Society
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• v.25 no.9
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• pp.67-76
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• 2009

The problems of bearing capacity, settlement and shear deformation occur when constructing a structure such as harbor, airport and bridge on soft ground of marine clay, silty clay or sandy soil. Various ground improvement methods are applied to obtain preceding settlement of soft ground and strength increase. In this study, to analyze the applicability of PBD method in deep soft ground, the compound drainage capacity test was operated in comparison with SD. As a result of the test, a minimum drainage capacity of drain material was estimated to be more than $10\;cm^3/sec$ at a more than $400\;kN/m^2$ and less than $5\;cm^3/sec$ at a more than $500\;kN/m^2$ confining pressure in case of single core PBD. In case of double core PBD, it was estimated to be more than $10\;cm^3/sec$ at a more than $500\;kN/m^2$ confining pressure.

• Geotechnical Engineering
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• v.39 no.5
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• pp.46-49
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• 2023

• Journal of the Korean Geotechnical Society
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• v.25 no.12
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• pp.37-45
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• 2009

Dredging and reclamation which have been conducted steadily for creation of new coastal area have the demerit of taking a long time. Hence, a lot of researches on acceleration of self-weight consolidation have been proceeding continuously. In this paper, 30 cases of laboratory self-weight consolidation tests were conducted to understand the application of PDF method, one of the self-weight consolidation acceleration methods, to domestic dredged soils. Acceleration effect of self-weight consolidation was confirmed through comparison and analysis of completion times and settlements of self-weight consolidation for none installed case and 4 kinds of common used PBD installed cases. As a result of the tests, installation of PBD before filling is effective for time reduction of self-weight consolidation.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.1198-1209
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• 2009

In this study, an experimental research on the acceleration effect of dredged soil's self weight consolidation with seepage consolidation and PBD was conducted. The middle-sized consolidation equipment had been manufactured in order to investigate the acceleration of sedimentation and self-weight consolidation by PBD and a lower drainage. Seepage pressure was applied to the PBD installed in the center of the test equipment and a drainage by seepage pressure was allowed. The comparison between cases with and without PBD and seepage pressure reveals that the quantity of drained water and the amount of settlement was nearly 1.2 times to 3.68 times greater in the case with PBD and seepage. Early consolidation completion and the use of reclaimed site are expected due to the acceleration of settlement and increase of the quantity of reclamation if PBD is installed while being reclaiming using the result of the research.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.5
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• pp.1300-1305
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• 2007

Plastic board drain is one of the methods to reinforce weak soil, and it has been widely used because of economical efficiency, convenience of construction, and ease of quality control. The weight of PBD equipment which places PBD perpendicularly underground in the depth of 40m has to be minimized to obtain convenience installation and movement while standing against press drawing load. In this study, the performance of stability was evaluated with stress distribution at the steel construction of former equipment by structural analysis: And the steel construction which can increase strength while reducing the weight was also presented. As a result of this study, presented construction can obtain more stability by use of the weight 700kg lighter than the former one.

• Journal of Industrial Technology
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• v.25 no.B
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• pp.63-71
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• 2005

This paper is an experimental result of investigating lateral soil movements at piled bridge abutments by using the centrifuge model facility. Three different centrifuge model experiments, changing the methods of ground improvement at bridge abutment on the soft clayey soil (no improvement, preconsolidation and plastic board drains (PBD), sand compaction pile (SCP) + PBD), were carried out to figure out which method is the most appropriate for resisting against the lateral soil movements. In the centrifuge modelling, construction process in field was reconstructed as close as possible. Displacements of abutment model, ground movement, vertical earth pressure, cone resistance after soil improvement and distribution of water content were monitored during and after centrifuge model tests. As results of centrifuge model experiments, preconsolidation method with PBD was found to be the most effective against the lateral soil movement by analyzing results about displacements of abutment model, ground movement and cone resistance. Increase of shear strength by preconsolidation method resulted in increasing the resistance against lateral soil movement effectively although SCP could mobilize the resistance against lateral soil movement. It was also found that installment with PBD beneath the backfill of bridge abutment induced effective drainage of excess pore water pressure during the consolidation by embanking at the back of the abutment and resulted in increasing the shear strength of clay soil foundation and eventually increasing the resistance of lateral soil movement against piles of bridge abutment.

• Journal of the Korean GEO-environmental Society
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• v.13 no.11
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• pp.43-50
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• 2012

In this research, the value of consolidation index was investigated. The range of the investigated standard deviation was analyzed and the deviation based settlement was calculated. Also, the compression index, which is the effect of the uncertainty in the ground was analyzed using the flimsy ground construction method. The settlement behavior in each embankment compaction stage was analyzed by applying the precompression load method, drainage expediting method, and displacement method through numerical analysis. In addition to the above, the settlement behavior was studied by analyzing the Piled Raft method which is stable for long term settlement. As a result, the final settlement amount based on average analysis results was that the settlement based on each of the average interpretation value, mean value of the maximum and minimum value and average compression index was different. The result of the comparison shows the difference in variation coefficient by the difference in time. Amongst them, the Piled Raft method shows the most consistent variation coefficient regardless of time and it also was least affected by the compression index of uncertainty.

• Geotechnical Engineering
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• v.19 no.8
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• pp.40-44
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• 2003

• Geotechnical Engineering
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• v.13 no.2
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• pp.39-54
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• 1997

Laboratory testings were carried out on plastic board drains (PBDs) using large scale test apparatus to evaluate the physical properties and the drainage performance. The test results reveal that the domestic products of PBDs are well compared with the foreign prod acts as far as the quality and drainage performance are concerned. It has also been confirmed that the discharge capacity decreases with time in such a way that the air bubbles are entrapped inside kinky PBDs and these air bubbles block the water flow through PBDs. It has been found that the vacuum pressure iseffectively applicable to recover the discharge capacity affected by the entrapped air bubbles.