Management of the Soils Discharged from Shield Tunnel Excavation
This paper presents a case history where about 950,000 m3 of the excavated soils (or construction sludge) generated from Hanshin Expressway shield tunnel construction site was properly managed and reused as reclamation material. Three challenges existed to proceed this entire project. First, separated tunnel and reclamation projects were firmly connected. Reclamation was planned and conducted to fill an area of 8.3 ha which was previously used as an old lumber yard and expected to be an industrial space. The entire project connected a series of highway construction generating the excavated soils and land reclamation project. This type of project was the first attempt in Japan. Second, ICT (information and communication technology) based on the electronic toll collection (ETC) system was applied to manage the soils. In this project, the ETC manifest system was developed and operated to secure traceability concerning the transportation of a large amount of excavated soils. This system improves the efficiency of issuing manifests, minimizes traffic congestion, and avoids overloaded vehicles. Third, to avoid adverse subsidence of land and facilities adjacent to the reclamation, several countermeasures were conducted, such as improvements of reclaimed and original grounds as well as consideration of reclamation procedure. Excavated soils were subjected to soil improvement to obtain sufficient mechanical properties as reclamation material at a soil improvement plant installed at the site next to the reclamation site. Gypsum-based stabilizing agent was applied to secure the neutral condition in pH. A ground improvement method which is able to improve the ground under ripraps was applied to the original ground beneath the revetments, based on the numerical analysis of ground deformation.
KeywordsExcavated soil Reclamation Subsidence ETC Manifest System
We would like to offer special thanks to Osaka Prefecture and Sakai City (for the construction work entities of Yamatogawa Route of Hanshin Expressway), The Ports and Harbors Bureau, Osaka City (for the land formation project of Lumber Yard No. 6), and Toyo Construction Co., Ltd. (for reclamation works), for their important contribution to “Joint Project for Effective Reuse of the Soils”.
- 1.Hanshin Expressway Company Limited: Outline and history of Yamatogawa Route Project. http://www.hanshin-exp.co.jp/company/torikumi/building/yamatogawa/files/YAMATOGAWA_OMOTE_2017n.pdf.pdfGoogle Scholar
- 2.Hanshin Expressway Engineering Company Limited: Recycling project of generated soil, background before the start of project https://www.hex-eng.co.jp/functions/recycle/recycle04.html
- 3.Yamaguchi Y, Mizuhara K, Mizuta K, Takemika T, Katsumi T, Kamon M (2012) Management of the soils discharged from shield tunnel excavation using ETC system. In: The international workshop on ICT in geo-engineeringGoogle Scholar
- 4.Osaka Prefecture, Sakai City, and Hanshin Expressway Company Limited (2008) Recycle Examination Committee on Construction Sludge from Yamatogawa Route Shield Works “Reuse Project of Yamatogawa Route Shield Construction Sludge (draft)” 25 February 2008. https://www.hanshin-exp.co.jp/topics2/1203915884F.pdf
- 5.Tomizawa Y, Yamana M, Mizuta K, Takemika T, Inagaki M, Katsumi T, Kamon M (2017) “A joint initiative for recycling soil generated by shield tunneling excavation, Hanshin Expressway”. In: The 28th annual conference of Japan society of material cycles and waste managementGoogle Scholar
- 6.Mizuta K, Takemika T, Takata H, Tatebe M, Gotanda H, Tomizawa Y, Yamaguchi Y, Imaki H, Katsumi T, Kamon M (2011) “Development and introduction of transport management system of construction wastes utilizing ETC”. In: The 23rd annual conference of Japan society of material cycles and waste managementGoogle Scholar
- 7.Tomizawa Y, Yamaguchi Y, Takemika T, Mizuta K, Fujiwara T, Katsumi T, Kamon M (2018) Application of traceability technology in reuse of construction wastes - Case study of Yamatogawa Route, Hanshin Expressway. In: The 10th Japan national symposium on environmental geotechnology, September 2018Google Scholar
- 8.Nikkei Construction (2011) June 27 published by Nikkei Business Publications Inc., pp 8–12, June 2011Google Scholar
- 9.Journal of Civil Engineering (2011) Office Space Company Limited., pp 21–23, July 2011Google Scholar