| Project/Area Number |
06555135
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| Research Category |
Grant-in-Aid for Scientific Research (A)
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| Allocation Type | Single-year Grants |
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| Section | 試験 |
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| Research Field |
Geotechnical engineering
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| Research Institution | HOKKAIDO UNIVERSITY |
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Principal Investigator |
TOKI Shosuke Hokkaido Univ., Fac.of Eng., Prof., 工学部, 教授 (50001136)
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| Co-Investigator(Kenkyū-buntansha) |
TATEISHI Akira Taisei Corp., Civil Eng.Div., Senior Engineer, 設計部, 課長
YAMASHITA Satoshi Kitami Inst.of Tech., Fac.of Eng., Asso.Prof., 工学部, 助教授 (00174673)
MIURA Kinya Hokkaido Univ., Fac.of Eng., Asso.Prof., 工学部, 助教授 (40190582)
MIURA Seiichi Muroran Inst.of Tech., Fac.of Eng., Asso.Prof., 工学部, 助教授 (00091504)
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| Project Period (FY) |
1994 – 1996
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| Project Status |
Completed (Fiscal Year 1996)
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| Budget Amount *help |
¥7,000,000 (Direct Cost: ¥7,000,000)
Fiscal Year 1996: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1995: ¥1,800,000 (Direct Cost: ¥1,800,000)
Fiscal Year 1994: ¥4,400,000 (Direct Cost: ¥4,400,000)
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| Keywords | Torsional shear test / Liquefaction / Flow failure / Ocean wave loading / Earthquake / Sandy soil / Volcanic soil / Small strain / 変形特性 / 試験装置 / 破砕性 / 模型実験 / 三軸試験 / 液状化解析 / 火山灰質土 / 繰返し変形特性 |
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| Research Abstract |
In this study, low cost, high resolution and high performance direct drive motor (DDM) used as axial and torsional loading equipment of torsional shear apparatus. In this DDM,changes of position, torque, speed control mode can be done easily by signals from a computer through the RS232C during testing.
To examine the effects of loading controlled conditions on the cyclic deformation characteristics of sand under wide range of strain level, axial load (torque) and axial displacement (rotation angle) controlled cyclic triaxial (torsional) shear tests were performed by the above DDM loading system. And also, displacement and load controlled undrained cyclic triaxial and torsional tests to obtain the liquefaction strength were performed.
Test result showed that :
1) Axial load (torque) and axial displacement (rotation angle) controlled tests under wide range of strain levels can be performed by the developed loading equipment usign DDM.
2) In the load controlled undrained cyclic test, the shear modulus and the damping ratio are not continuously measured at strain revel upper about 0.1%. The reason for this is that the strain kincreases rapidly due to the decrease of effective confining pressure. On the other hand, in the displacement controlled undrained cyclic test. cyclic deformation properties are continuously measured at large strain level.
3) There existed a unique rule between results of load and displacement controlld liquefaction tests. This rule was independent of the relative density, the loading cycles and the types of tests (triaxial and torsional). On the basis of this relation, the cyclic strength in load controlled tests can be evaluated to some extent by performing displacement controlled cyclic tests.
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