Research of the behavior for buried flexible outlet conduit under the earth dam

• Project/Area Number: 14360143
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Irrigation, drainage and rural engineering/Rural planning
• Research Institution: Kobe University
• Principal Investigator: KAWABATA Toshinori Kobe University, Faculty of Agriculture, Associate Professor, 農学部, 助教授 (20335425)
• Co-Investigator(Kenkyū-buntansha): UCHIDA Kazunori Kobe University, Faculty of Agriculture, Professor, 農学部, 教授 (80111946) ; TANAKA Tsutomu Kobe University, Faculty of Agriculture, Professor, 農学部, 教授 (20144602)
• Project Period (FY): 2002 – 2004
• Project Status: Completed (Fiscal Year 2004)
• Budget Amount: ¥15,100,000 (Direct Cost: ¥15,100,000); Fiscal Year 2004: ¥1,100,000 (Direct Cost: ¥1,100,000); Fiscal Year 2003: ¥3,200,000 (Direct Cost: ¥3,200,000); Fiscal Year 2002: ¥10,800,000 (Direct Cost: ¥10,800,000)
• Keywords: Geotechnical Engineering / Underground Structure / Model Tests / Earth Pressure / Settlement / Irrigation Pond / Numerical Analysis

Research Abstract

The behavior of buried flexible pipe is influenced to a considerable extent by the properties of the backfill materials. Recently, geosynthetics are commonly used in retaining wall for reinforcement. And flexible pipe is used for drainage in such embankment.
However, the behavior of buried flexible pipe in the retaining wall reinforced by geosynthetics is not clear.
Experiments using a middle-sized steel test pit were carried out to examine the behavior of a flexible pipe buried in a reinforced embankment with settlement. A bi-axial load cell was developed in order to accurately measure the load acting on the buried pipe, and a model pipe, which was equipped with 20 such load cells was made.
The result showed that with settlement of the pipe, the arching action of the backfill progress, and the vertical load that acts on the pipe greatly decreases.
In addition, it was found that when backfill with sand and geogrid was used, the vertical load act on the pipe was distributed by the geogrid, hence decreasing by approximately 25% the overburden load.
In the future, it is necessary to examine the effects of the installed position of the geogrid and number of layers of the geogrid.

Research Products

• [Journal Article] Lateral Loading Experiments on Thrust Protecting Method for Buried Bend with Geogrid (2005)
  • Author(s): Toshinori, Kawabata
  • Journal Title: Proceedings of Geofrontiers 2005, ASCE Austin, TX, USA GSP140 Pages: 1-8
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Uplift Mechanism of Underground Structures in Dry Sand Subjected to Cyclic Simple Shear by DEM (2005)
  • Author(s): Toshinori, Kawabata
  • Journal Title: Proceedings of 15th International Offshore and Polar Engineering Conference, ISOPE2005, Seoul, Korea (印刷中)
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Lateral Loading Experiments on Thrust Protecting Method for Buried Bend with Geogrid (2005)
  • Author(s): Kawabata1, T
  • Journal Title: Proceedings of Geofrontiers 2005, ASCE GSP140 Pages: 1-8
• [Journal Article] Lateral Loading Tests for Buried Pipe with Geosynthetics (2004)
  • Author(s): Toshinori, Kawabata
  • Journal Title: Proceedings of GeoTrans, ASCE, LA, USA Vol.1 Pages: 609-616
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Distribution of Traffic Loads for Shallowly Buried Pipe by D.E.M.Analyses (2004)
  • Author(s): Toshinori, Kawabata
  • Journal Title: Proceedings of Pipeline 2004, ASCE, SanDiego, USA CD Dir.9B Pages: 1-10
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Lateral Loading Tests for Buried Pipe with Geosynthetics (2004)
  • Author(s): Kawabata, T., Uchida, K., Ling, H.I., Nakase, H., Sawada, Y., Hirai, T., Saito, K.
  • Journal Title: Proceedings of Geo-Trans 2004 (ASCE) Vol.1 Pages: 609-616
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] Lateral Loading Tests for Buried Pipe with Geosynthetics (2004)
  • Author(s): Kawabata1, T
  • Journal Title: Proceedings of Geo-Trans 2004, ASCE Vol.1 Pages: 609-616
• [Journal Article] Experiments on Buried Flexible Pipe Using Backfill of Cover with Geosynthetics (2003)
  • Author(s): Toshinori, Kawabata
  • Journal Title: New Pipeline Technologies, Security, and Safety, ASCE Vol.2 Pages: 1271-1278
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] D.E.M.Analyses on Behavior of Shallowly Buried Pipe Subject to Traffic Loads (2003)
  • Author(s): Toshinori, Kawabata
  • Journal Title: New Pipeline Technologies, Security, and Safety, ASCE Vol.2 Pages: 1218-1227
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Experiments on Buried Flexible Pipe Using Backfill of Cover with Geosynthetics (2003)
  • Author(s): Kawabata, T., Uchida, K., Hirai, T., Mohri, Y., Ling H.I., Koyama, N.
  • Journal Title: New Pipeline Technologies, Security, and Safety (ASCE) Vol.2 Pages: 1271-1278
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] D.E.M. Analyses on Behavior of Shallowly Buried Pipe Subject to Traffic Loads (2003)
  • Author(s): Kawabata, T., Uchida, K, Ariyoshi, M., Nakase, H.Mohri, Y., Ling, H.I
  • Journal Title: New Pipeline Technologies, Security, and Safety (ASCE) Vol.2 Pages: 1218-1227
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] Experiments on Buried Flexible Pipe Using Backfill of Cover with Geosynthetics (2003)
  • Author(s): Kawabata, T
  • Journal Title: New Pipeline Technologies, Security, and Safety, ASCE Pages: 1271-1278
• [Journal Article] Distribution of Traffic Loads for Shallowly Buried Pipe by D.E.M. Analyses
  • Author(s): Kawabata, T., Ariyoshi, M., Uchida, K., Ling, H.I., Nakase, H., Sawada, Y., Mohri, Y.
  • Journal Title: Proceedings of Pipeline 2004 (ASCE SanDiego, USA) CD Dir 9B Pages: 1-10
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] Lateral Loading Experiments on Thrust Protecting Method for Buried Bend with Geogrid
  • Author(s): Kawabata, T., Uchida, K., Sawada, Y.Hirai, T., Saito, K.
  • Journal Title: Proceedings of Geofrontiers 2005 (ASCE, Austin, TX, USA) Vol.GSP140 Pages: 1-8
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] Uplift Mechanism of Underground Structures in Dry Sand Subjected to Cyclic Simple Shear by DEM
  • Author(s): Kawabata, T., Uchida, K., Ooishi, J., Nakase, H.
  • Journal Title: Proceedings of 15th International Offshore and Polar Engineering Conference, ISOPE2005, Seoul, Korea (now printing)
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] Kawabata, T: "Experiments on Buried Flexible Pipe Using Backfill of Cover with Geosynthetics"New Pipeline Technologies, Security, and Safety, ASCE. 1271-1278 (2003)