| Project/Area Number |
16560429
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Geotechnical engineering
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| Research Institution | The University of Tokyo |
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Principal Investigator |
SATO Takeshi The University of Tokyo, Institute of Industrial Science, Research Associate, 生産技術研究所, 助手 (30092224)
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| Co-Investigator(Kenkyū-buntansha) |
KOSEKI Junichi The University of Tokyo, Institute of Industrial Science, Professor, 生産技術研究所, 教授 (30272511)
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| Project Period (FY) |
2004 – 2005
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| Project Status |
Completed (Fiscal Year 2005)
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| Budget Amount *help |
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 2005: ¥1,200,000 (Direct Cost: ¥1,200,000)
Fiscal Year 2004: ¥2,300,000 (Direct Cost: ¥2,300,000)
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| Keywords | True triaxial test / Design chart of soil test apparatus / Database of charts / Plane strain compression test / Image analysis / Coarse geo-material / Shear band / Strain localization |
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| Research Abstract |
Investigations were conducted to extend the functions of a large scale true triaxial testing apparatus and to develop database for design charts of several types of laboratory soil test apparatuses. In order to perform plane strain compression tests, confining plates with high capacity and pedestal with roller bearings were newly introduced. Large scale plane strain compression tests and image analysis of the test results were performed on compacted Chiba gravel. Long-term creep loading system was also newly introduced, and a database was made by collecting design charts of a variety of laboratory soil test apparatuses that were designed and assembled by the investigators.
The following outcomes have been obtained based on the development of the large scale plane strain compression apparatus and its usage.
1. The existing true triaxial testing apparatus could not be applied to plane strain compression tests with image analysis, since the existing confining plates were not transparent. Therefore, a transparent confining plate has been newly introduced for taking digital photographs through it. Thus, image analyzes of the local deformation of specimen have become possible.
2. The existing apparatus employed lubrication layers at interfaces between the specimen, and top cap and pedestal, while the bottom layer were occasionally damaged by heavy compaction applied to prepare dense specimens. Therefore, a pedestal with roller bearings has been newly introduced to ensure the lateral movement of the specimen, in particular after formation of shear band.
3. By using the new system, a series of plane strain compression tests was conducted on compacted Chiba gravel. The distributions of local strains before and after the shear band formation were compared to each other, including the thickness of the shear band, displacements in the parallel and perpendicular directions of the shear band. Effects of large amplitude cyclic loading history were also investigated.
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