| Project/Area Number |
63460213
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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 |
農業土木
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| Research Institution | Tottori University |
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Principal Investigator |
TSUGE Miichi Tottori University, Agriculture, Professor, 農学部, 教授 (20032071)
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| Co-Investigator(Kenkyū-buntansha) |
HATTORI Kunio Tottori University, Agriculture, Associate Professor, 農学部, 助教授 (00032300)
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| Project Period (FY) |
1988 – 1990
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| Project Status |
Completed (Fiscal Year 1990)
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| Budget Amount *help |
¥7,500,000 (Direct Cost: ¥7,500,000)
Fiscal Year 1990: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1989: ¥1,500,000 (Direct Cost: ¥1,500,000)
Fiscal Year 1988: ¥5,000,000 (Direct Cost: ¥5,000,000)
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| Keywords | Lower Quality Aggregate / Freezing and Thawing Test / Durability Factor / Non-destructive Test / Dynamic Modulus of Elasticity / Durability of Concrete / Bulk Density of Concrete / Compressive Strength / 低品質骨材 / 凍結・融解試験 / AE減水剤 / コンクリートの耐久性 / コンクリートの密度 |
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| Research Abstract |
From 1981, we have studied on the possibility of "Masa-do" for use as fine aggregate in concrete. The term "Masaーdo" is applied to residual soil which is obtained from decomposed granite soil in japan. After many experiments, We indicated that "Masa-do" can be used ad fine aggregate in concrete. As a next step, we started the experiment on the resistance of concrete to freezing and thawing action from 1988. Masa-do which was used for the experiment had a fineness modulus of between 3.20 to 3.60 and a bulk density of 2.54. In the freezing and thawing test. A prism with 10 cm square and 40 cm long was used, and the air entraining agent was used. In this test, the following factors were measured;
(1) Weight and volume change
(2) Bulk density
(3) Dynamic modulus of elasticity
(4) Ultra sonic velocity
(5) Flexural strength (after the end of freezing and thawing test)
(6) Compressive strength (after the end of freezing and thawing test)
From the experiments carried out for three from 1988. The following results were obtained.
(1) The concrete made from Masa-do as fine aggregate without air entraining agent has a little lower resistance to freezing and thawing than that of concrete made from river sand. (2) The air entraing agent improve the resistance of concrete ro freezing and thawing. The air content which gives the good resistance of concrete to frost action is 4 to 6%. (3) To evaluate the resistance of concrete to frost action, the durability factor DF based on the dynamic modulus of elasticity is best, and the durability factors DU based on the ultra sonic velocity can be used too.
(4) The bulk density of concrete is not decreased by the freezing and thawing action, because the these actions is not a chemical attack.
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