Manufacturing Method and Properties of Core and WHD Made of Virgin PP and Recycle PP

Sung-Woo Cho; Im-Rak Lee; Tae-Young Park; Eun-Chul Shin

doi:10.12814/jkgss.2026.25.3.001

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2026 Vol.25, Issue 3 Next Page

Research Article

Manufacturing Method and Properties of Core and WHD Made of Virgin PP and Recycle PP 신재 및 재활용 폴리프로필렌 소재를 이용한 코어재 및 날개형 수평배수재의 제조방법과 물성 평가

30 September 2026. pp. 1-14

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Abstract

A integrated method of PHD+PVD, “Top-fixed drainage method”, connects the end of an installed PVD to the upper part of PHD and it may face resistance in drainage due to limited permeability of the filter. Because of this reason, most of the pore water does not pass through the core part(water channel) in PHD and it is dispersed into the nearby ground. Therefore, consolidation time is prolonged while the moisture content of ground increases. In this study, WHD(Wing Horizontal Drain) prototypes have been developed to improve the structural issues of conventional PHD and to minimize the loss of pore water into the ground. A mass-production system for WHD product can be furnished by ensuring stable productivity in the key processes including mount-shape core using a molding roller and ultrasonic thermal bonding between filter and wing 1, 2. Four different prototypes of WHD are manufactured by combining two core materials either virgin or recycle PP with two types of filter, PP and PET nonwoven fabrics. Based on these combined elements, totally 8-prototypes are made with single wing and double wings. The major engineering characteristics such as tensile property and water discharge capacity(WDC) of WHD products are also compared and analyzed. The recycle PP core shows almost no difference in physical properties comparison with the virgin PP core. In addition, a newly designed ‘drainage efficiency device’ is proposed to solve the issues with ‘ASTM D 4716’ and to analyze WDC of WHD+PVD+wing. The newly proposed method is called “Direct insertion drainage method” for testing of WHD+PVD+wing and it can be compared with “Top-fixed drainage method” for testing of PHD+PVD. Based on the laboratory WDC tests, the former drainage method has significantly improved WDC compared to the latter method when the landfill soil conditions of the construction site is especially very poor. The results of water discharge capacity with ‘drainage efficiency device’ indicate that the newly developed WHD contains an innovative wings and hence it can replace effectively the conventional PHD product.

Keywords

Soft ground improvement

Wing horizontal drain(WHD)

Prefabricated horizontal drain(PHD)

Direct insertion drainage method

Top-fixed drainage method

Water discharge capacity

현재 적용되고 있는 수평배수재와 수직배수재의 일체화 공법인 상부거치식 배수공법에서 수직배수재를 통해 지표층으로 배출된 지중 간극수는 수평배수재의 필터재 표면에 배출되지만, 필터재의 제한적인 투수율로 인해 배수저항을 받게 된다. 그 결과, 간극수의 대부분은 수평배수재 코어재(배수유로)로 유입되지 못하고 지중으로 재유실되어 점토지반의 압밀시간이 지연되는 문제가 발생한다. 본 연구에서는 이러한 수평배수재의 구조적 문제를 개선하고 간극수의 유실을 최소화할 수 있는 날개형 수평배수재 시제품을 개발하였다. 주요 핵심공정인 성형로울러에 의한 코어재 단면구조(산형격자)의 성형 및 날개편 1, 2와 필터재의 초음파 열접착에 대한 안정된 생산성 확보를 통해 날개형 수평배수재의 양산시스템을 구축하였다. 날개형 수평배수재(WHD)는 코어재 2종(신재, 재활용 PP)과 필터재 2종(PP, PET 부직포)을 조합해 4종류의 시제품을 생산하였고, 이를 기준으로 한방향과 양방향 날개편을 가지는 최종 8종의 시제품을 제작하여 주요 물성을 비교 분석하였다. 재활용 PP(R-PP) 코어재는 우수한 물성을 나타내었으며 신재 PP(V-PP) 코어재의 물성 대비 유사한 초기 성능을 보였다. 또한, 수평배수성능의 평가를 위해 채택되고 있는 ASTM D 4716 시험법 규격에 대한 문제점을 보완하고자 새로운 배수성능 시험장치를 고안하여 날개형 수평배수재와 수평배수재의 배수성능을 비교 분석하였다. 날개형 수평배수재(직접삽입식 배수공법)은 시공 현장 조건이 가혹할수록 탁월한 배수성능을 유지하였고, 기존 수평배수재(상부거치식 배수공법)를 효과적으로 대체할 혁신적인 공법임을 확인할 수 있었다.

References

Bo, M. W. (2004), “Discharge capacity of prefabricated vertical drain and their field measurements”, Geotextiles and Geomembranes, Vol.22, No.1-2, pp.37-48.

10.1016/S0266-1144(03)00050-5

Cho, S. D. (2008), “Chapter 6: Utilization of eco-friendly natural fiber drains”, Korean Geosynthetics Society Short-term Course.

Cho, S. M., Park, S. I., Jung, M. H. and Kim, S. H. (2008), “Applications of the fiber mat for the horizontal drainage on the surface of the vertical drain installed silty clay deposits”, Proceedings of the Korean Society of Civil Engineers Conference, pp.909-912.

Cho, S. W. (2022), A Study on the Improvement of Manufacturing Method and Evaluation of Drainage Efficiency of Wing Horizontal Drain, Master Thesis, Tech University of Korea.

Kim, H. J. and Kim, N. Y. (2012), “Compatibility of prefabricated horizontal drains on the soft ground”, Proceedings of the Korean Geosynthetics Society Spring Conference, pp.169-173.

Kim, S. S., Shin, H. Y., Hyun, C. and Park, J. B. (2002), “Experimental study on mechanical properties of horizontal drain board”, Journal of the Korean Society of Civil Engineers, Vol.22, No.4-C, pp.433-441.

Lee, D. W. and Noh, J. J. (2013), “Clogging behavior of recycled aggregates and crushed stone as horizontal drains in soft ground”, Journal of Agricultural Science, Institute of Agricultural Science, Chungnam National University, Vol.40, No.3, pp.253-260.

10.7744/cnujas.2013.40.3.253

Lee, G. Y. (2012), Effect analysis of composite discharge capacity for PBD considering the field conditions, Ph.D. Thesis, University of Seoul, pp.1-10.

Lee, I. R. and Oh, W. (2013), “Introduction of horizontal drainage method (Hori-Drain) as a substitute for sand mat in soft ground improvement”, Journal of the Korean Geosynthetics Society, Vol.12, No.3, pp.19-22.

Lee, I. R. and Oh, W. (2020), “Manufacturing apparatus of horizontal drainer with wings”, Korean Patent, No.10-2113833.

Lee, J. Y., Chun, H. P., Jung, W. C. and Lim, H. S. (2008), “A study on utilization of recycled aggregates as lateral drain for soft ground improvement”, Journal of the Korean Geotechnical Society, Vol.24, No.10, pp.5-15.

10.7843/kgs.2011.27.10.005

Onoue, A. (1988), “Consolidation by vertical drains taking well resistance and smear into consideration”, Soils and Foundations, Vol.28, No.4, pp.165-174.

10.3208/sandf1972.28.4_165

Park, T. Y., Lee, I. R. and Oh, W. (2018), “Insertion type horizontal drainage method for soft ground improvement to maximize drainage efficiency”, Proceedings of the Korean Geosynthetics Society Fall Conference, pp.5-6.

Park, T. Y. and Cho, S. W. (2021), “Nonwoven fabrics for producing a horizontal drainer and a horizontal drainer having wing part using the same”, Korean Patent, No. 10-2257758.

Shin, E. C., Kim, S. H. and Kang, J. G. (2007), “Evaluation of required discharge capacity of PVD with various core types”, Journal of the Korean Geosynthetics Society, Vol.6, No.2, pp.1-8.

Information

Publisher :Korean Geosythetics Society
Publisher(Ko) :한국지반신소재학회
Journal Title :Journal of the Korean Geosynthetics Society
Journal Title(Ko) :한국지반신소재학회 논문집
Volume : 25
No :3
Pages :1-14
Received Date : 2026-06-05
Revised Date : 2026-07-10
Accepted Date : 2026-07-13
DOI :https://doi.org/10.12814/jkgss.2026.25.3.001

Journal of the Korean Geosynthetics Society ISSN:2508-2876(Print) 2287-9528(Online) 한국지반신소재학회 논문집

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