2007 Fiscal Year Final Research Report Summary
Change in flowability of self-compacting concrete due to pumping
Project/Area Number |
18360210
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Research Category |
Grant-in-Aid for Scientific Research (B)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Civil engineering materials/Construction/Construction management
|
Research Institution | Kochi University of Technology |
Principal Investigator |
OUCHI Masahiro Kochi University of Technology, Faculty of Engineering, Associate Professor (80301125)
|
Project Period (FY) |
2006 – 2007
|
Keywords | self-compacting concrete / pumping / shear stress / superplasticizer / adsorption / relative surface area / change in flowability |
Research Abstract |
The mechanism for the reduction in the flowability of fresh mortar of self-compacting concrete was clarified. The main cause for the reduction in the flowability due to pumping was shear stress generated in the mortar rather than the compressive stress. Shear stress dispersed the coagulated particles of cement and that resulted in higher amount of free water and less amount of supeiplasticizer adsorbed to the unit surface area of the particles of cement. That led to lower viscosity and deformability ofthe fresh mortar. The degree ofthe reduction in the viscosity and defonnability ofthe mortar was affected by the water to cement ratio and the initial mixing energy.
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