Segregation Resistance of Fresh Concrete
| Project/Area Number |
05452225
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
土木材料・力学一般
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| Research Institution | Saitama University |
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Principal Investigator |
MACHIDA Atshuiko Saitama Univ., Dept.of Eng., Professor, 工学部, 教授 (50008869)
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| Co-Investigator(Kenkyū-buntansha) |
IWASHITA Kazuyoshi Saitama Univ., Dept.of Eng., Asso.Professor, 工学部, 助教授 (40203377)
MUTSUYOSHI Hiroshi Saitama Univ., Dept.of Eng., Asso.Professor, 工学部, 助教授 (60134334)
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| Project Period (FY) |
1993 – 1994
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| Project Status |
Completed (Fiscal Year 1994)
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| Budget Amount *help |
¥3,000,000 (Direct Cost: ¥3,000,000)
Fiscal Year 1994: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1993: ¥2,200,000 (Direct Cost: ¥2,200,000)
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| Keywords | segregation resistance / slump test / flow test / discreat element method / tension allowance in spring / friction constant / dash-pot constant / spring cpnstant / 材料分離 / 流動解析 / スランプ |
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| Research Abstract |
Two kinds of flow test and slump test were carried out on six kinds of concrete, and these results were analyzed by using the discrete element method which was established last year. The followings were made clear from the tests and analysis.
(1) The test results confirmed that slump flow value and flow time are independent from each other, that is, the former relates to deformation potential, whereas the latter to defor-mation velocity.
(2) It was shown that the discrete element method can be applied to analysis of behavior of fresh concrete, if tension allowance in spring to express viscosity of mortar, friction constant between elements to express irregularities of surfaces of coarse aggregates and, if necessary, friction constant between elements and bottom surface are introduced as well as spring constant and dash-potconstant which are used in analysis of soils and if these constants can be assumed properly.
(3) It was shown that tension allowance in spring plays dominant role in analysis both of slump test and flow tests. This fact corresponds to the fact that viscosity of mortar relates to both of deformation potential and deformation velocity.
(4) It was shown that friction constant between elements linearly related to slump flow value and that flow time does not change if the constant changes within some range but it increases linearly if the constat increases outside the range. It can be said from this fact that interaction of coarse aggregate can be expressed precisely if the friction constant is determined properly.
(5) It was shown that the behavior of fresh concrete which has same deformation potential but different deformation velocity can be expressed, if dash-pot constant is selected properly.
Segregation resistance of fresh concrete can hardly be made clear by experiments but, as described above, it was shown that the discrete element method has a possibility to make it clear, if the accuracy is improved.
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Report
(3 results)
Research Products
(13 results)
