著者
Takayuki Shimaoka Koji Kumagai Takeshi Katsumi Michio Iba
出版者
公益社団法人 地盤工学会
雑誌
Japanese Geotechnical Society Special Publication (ISSN:21888027)
巻号頁・発行日
vol.2, no.70, pp.2385-2390, 2016-01-31 (Released:2016-01-29)
参考文献数
5

A number of temporary storage sites have been commissioned to contain soils and wastes generated from the decontamination works after the accident at Tokyo Electric Power Company’s Fukushima Dai-ichi Nuclear Power Plant. At these sites, volume reduction has been observed in the flexible container bags caused by the dehydration and decomposition of the decontamination waste inside. This situation leads to uneven settlement of the top of these flexible container bags in these temporary storage sites, and might result in problems such as leakage through top and bottom liners installed to contain these container bags. To deal with these problems immediately, the Geomembrane Technical Committee, Japan Chapter of International Geosynthetics Society has conducted deliberations and made reports on procedures for selection and installation of storage containers that are to prevent polluted water from leaking outside of storage sites, structures, and barrier materials, a new inspection procedure for seaming of cover geomembranes, installation of cover materials that are to counter uneven settlement of soil, and also temperature control procedures to prevent natural ignition of waste. This paper summarizes the deliberations and the procedures adopted.
著者
Takayuki Masuo Masatoshi Ishida Masaki Nishimura Tomoyuki Akai
出版者
公益社団法人 地盤工学会
雑誌
Japanese Geotechnical Society Special Publication (ISSN:21888027)
巻号頁・発行日
vol.2, no.70, pp.2391-2395, 2016-01-31 (Released:2016-01-29)
参考文献数
4

We have developed gas-permeable/waterproof sheet (GPWS), comprising a micro-porous sheet which is waterproof and have gas permeability, coated with nonwovens to protect and reinforce it, and carried out many experiments in both laboratories and fields. GPWS has been applied as cover sheet for temporary storage sites of decontamination waste due to the Fukushima nuclear accident. On the other hand, geomembrane which is waterproof but gas-impermeable has also employed as cover sheet of the decontamination waste in conjunction with gas-vent pipes. In this study, temperature and oxygen-concentration of the decontaminated wastes, over which GPWS and geomembrane were installed respectively, were experimentally measured in real temporary storage site to compare the influence of weather condition. As the results, it was demonstrated that GPWS can achieve sufficient performances as the cover sheet in that both temperature and oxygen-concentration, closely relating with the consistency of gas permeability in the cover system, was less influenced by weather condition.
著者
Marwan Alzaylaie Aly Abdelaziz
出版者
公益社団法人 地盤工学会
雑誌
Japanese Geotechnical Society Special Publication (ISSN:21888027)
巻号頁・発行日
vol.2, no.51, pp.1778-1783, 2016-01-31 (Released:2016-01-29)
参考文献数
8

Pearl Jumeira is an artificial offshore land formation located in Jumeira Beach in the Arabian Gulf and is constructed from Dubai-sourced reclaimed sand and locally sourced rockworks. Reclaimed sand was dredged from known borrow pits in Dubai waters. The island will cover approximately 8.3 million square feet of land (fully serviced with all infrastructure requirements) consisting of more than 3.0 million square feet of residential villa plots and over 90,000 square feet of retail, community, and educational facilities. The current paper presents a geotechnical case study on this reclaimed island in terms of: The geotechnical design, the construction stages, and the ground investigation results. In the geotechnical design stage, soil properties of the reclaimed land were investigated to achieve the design bearing capacity and to assess the risk of liquefaction. In the geotechnical construction stage, soil improvement technologies such as vibro compaction and surface compaction were used. In the soil investigation stage, a set of soil tests were conducted in order to achieve the geotechnical design. These tests include Standard Penetration Test (SPT), Unconfined Compressive Strength Test (UCS), Piezocone Penetration Tests (CPTU), Zone Load Test, Particle Size Distribution (Sieve Analysis), etc.... The thickness of the reclamation fill varies across the site but is typically in the order of 10 m to 15 m and consists primarily of clean sand with lenses of silty materials. The materials below the pre-reclamation seabed comprise of layers of sand and silty materials of varying thicknesses, underlain by the Calcisiltite/Calcarenite bedrock between -10 m and -15 m Dubai Municipality Datum (DMD).
著者
Kazuo Ide
出版者
公益社団法人 地盤工学会
雑誌
Japanese Geotechnical Society Special Publication (ISSN:21888027)
巻号頁・発行日
vol.2, no.2, pp.135-142, 2016-01-31 (Released:2016-01-29)
参考文献数
4

As a result of The Great East Japan Earthquake, approximately 28 million tons of disaster wastes (such as disaster debris and tsunami deposits) were generated in the three prefectures of Iwate, Miyagi, and Fukushima, mainly due to the tsunami. The waste treatment on this massive scale would normally take more than a decade. For the local recovery and reconstruction, disaster waste treatment was the first step, and its early treatment was essential. Two months after the disaster, the government prepared a master plan for completing the treatment by the end of March 2014, approximately three years after the earthquake, focusing on recycling of the waste. Due to the enormous amount of waste and its complicated physical properties, disaster waste treatment posed a number of problems. However, the construction industry and related parties worked on the task with a sense of mission, completing the treatment in Iwate and Miyagi prefectures by the end of March 2014, as specified by the national government, and achieving a recycling ratio of nearly 90% based on thorough recycling and reuse. Materials recycled through treatment were used for embankment and backfilling, etc. in public reconstruction projects.
著者
Kenichi Sato Takuro Fujikawa
出版者
The Japanese Geotechnical Society
雑誌
Japanese Geotechnical Society Special Publication (ISSN:21888027)
巻号頁・発行日
vol.3, no.2, pp.65-70, 2015-09-30 (Released:2016-05-28)
参考文献数
3
被引用文献数
1 1

The recent increase in the generation and use of coal fly ash by electric power stations and various industries has contributed to Japan developing technology to facilitate the utilization of fly ash as ground material, including the use of fly ash for fills and embankments, pavement and subbase courses, subgrade stabilizations, landfill cover, soil improvement, land reclamation, slurried flowable ash and water pollution control. This paper describes the state of the art related to coal fly ash utilization as geo-material in Japan. In particular, this paper describes the material properties and technology associated with each technique. As coal fly ash contains a very small amount of heavy metal which should be considered for geo-environmental safety, this paper also discusses quality and inspection techniques for coal fly ash materials.
著者
Hemanta Hazarika Amizatulhani Abdullah
出版者
The Japanese Geotechnical Society
雑誌
Japanese Geotechnical Society Special Publication (ISSN:21888027)
巻号頁・発行日
vol.2, no.68, pp.2336-2341, 2016-01-31 (Released:2016-01-29)
参考文献数
14
被引用文献数
1

This study focuses on accumulation of basic data on deformation and energy absorbing characteristics of geosynthetics (recycled tire chips and geogrid), which are used as liquefaction prevention materials for shallow foundations. Because tire chips have high compressibility, decrease of bearing capacity and excessive differential settlement of the foundation ground may arise. A new reinforcement method, using gravel mixed tire chips layer and layers of geogrid, was proposed to compensate for the inadequate bearing capacity and suppress differential settlement. In this study, the deformation and energy absorbing characteristics of tire chips and gravel mixed tire chips were made clear by performing direct shear test under dynamic loading using a large scale shearing device. Based on the results, it was found that the vibration-absorbing energy of tire chips decreases as the gravel fraction increases. Considering the pros and cons, we could arrive at the conclusion that the sample with 50% gravel mixture was the most effective. It was also confirmed that the rigidity of gravel mixed tire chips was improved through reinforcement by geogrid.
著者
Q. Tang H.Y. Wang H. Chen P. Li X.W. Tang T. Katsumi
出版者
公益社団法人 地盤工学会
雑誌
Japanese Geotechnical Society Special Publication (ISSN:21888027)
巻号頁・発行日
vol.2, no.53, pp.1845-1848, 2016-01-31 (Released:2016-01-29)
参考文献数
23

This paper studies the effects of bio-clogging on hydraulic conductivity of compacted soils used as landfill liners. Landfill leachate contains a large amount of microorganism and bacterial biomass, which was likely to cause bio-clogging in landfill liners. To interpret the effect of bio-clogging on hydraulic property of compacted clays, in this study, a series of laboratory-scale hydraulic conductivity tests were conducted. The long term hydraulic conductivity of compacted clays was measured with distilled water, landfill leachate and one type of nutrient solution. The laboratory test results show that the hydraulic conductivity of compacted clays permeated with distilled water stabilized at approximately 3.77 × 10-8 cm/s, and the hydraulic conductivity of compacted clays permeated with landfill leachate or nutrient solution ranged between 1.1 × 10-8 cm/s and 5.22 × 10-9 cm/s. Such a significant difference was attributed to the effect of bio-clogging. The microorganism and bacterial biomass reduced the hydraulic conductivity up to one order of magnitude. This study indicated that the bio-clogging is approximately a feasible method to create low-cost and low-hydraulic conductivity barriers by using locally available clayed soils.
著者
Keiichiro Shibata Hidenori Yoshida Naomichi Matsumoto
出版者
公益社団法人 地盤工学会
雑誌
Japanese Geotechnical Society Special Publication (ISSN:21888027)
巻号頁・発行日
vol.1, no.4, pp.7-10, 2015-08-30 (Released:2015-08-31)
参考文献数
8

The serious nuclear disaster in the Fukushima Daiichi nuclear energy plant of the Tokyo Electricity Power Company was occurred by the tsunami which was caused by the Great East Japan Earthquake on March 11, 2011. The radioactive materials emitted by the disaster were widely diffused in and around Fukushima prefecture including the Pacific Ocean by wind, rain and a flow of river. It can’t be always said that there is no risk of the condensation of radioactive materials in human’s body by ecological chain if fish take in radiation in the ocean contaminated by the radioactive materials. However the effective decontamination methods of the radioactive materials are not developed and the decontamination is less-advanced. The establishment of a new decontamination method is urgent need and indispensable in light of disadvantageous effect on ecological system. Thus, in this study, it is aimed to establish a new decontamination technology of radioactive materials deposited on seabed or lake bed. In particular, the new adsorption material which can adsorb radioactive materials is developed and the new method which can move them from the bottom sediment is proposed. The results obtained from various tests with or without the water circulation and the adsorption material indicate that the water circulation is effective and that the adsorption material has a great deal of potential in the decontamination of radioactive materials. It is expected that the proposed method and the developed adsorption material are efficient to remove radioactive materials from seabed or lake bed when they are expansively applied to the real decontamination.