Change in flowability of self-compacting concrete due to pumping

泵送引起的自密实混凝土流动性的变化

• 批准号: 18360210
• 负责人: OUCHI Masahiro
• 金额: $ 5.16万
• 依托单位: Kochi University of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2006
• 资助国家: 日本
• 起止时间: 2006 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18360210/
• 关键词: self-compacting concrete; pumping; shear stress; superplasticizer; adsorption; relative surface area; change in flowability; 自己充填モルタル; 流動性; セメント粒子の分散と凝集; セメント粒子の表面積; フレッシュモルタル; 変形性低下

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.

阐明了自我压缩混凝土新鲜砂浆的流动性降低的机制。降低泵送引起的流动性的主要原因是在砂浆中产生剪切应力，而不是压缩应力。剪切应力分散了水泥的凝结颗粒，这导致了更高量的游离水和较少的supeiplasticizer吸附到水泥颗粒的单位表面积上。这导致了新鲜砂浆的粘度和可变形性降低。砂浆粘度和剥落性的降低程度受水与水泥比和初始混合能的影响。

项目成果

Influence of viscosity agent on generation of bleeding from freshmortar using superpplasticizer (in Japanese)

增粘剂对使用高效减水剂的新鲜砂浆泌水产生的影响（日文）

• 发表时间: 2008
• 期刊: Proceedings of the 53rd JSCE Annual meeting
• 作者: Kita;R
• 通讯作者: R

Change in the flowability of self-compacting mortar due to external force in terms of water to cement ratio and mixing method (in Japanese)

自密实砂浆的流动性因水灰比和搅拌方法的外力变化（日文）

• 发表时间: 2008
• 期刊: Proceedings of the 53rd JSCE Annual meeting
• 作者: Nakayama;T
• 通讯作者: T

Self-compactability of fresh concrete in terms of dispersion and coagulation of particles of cement subject to pumping

新拌混凝土在泵送水泥颗粒的分散和凝结方面的自密实性

• 发表时间: 2008
• 期刊: Proceedings of the Third North American Conference on the Design and Use of Self-Consolidating Concrete
• 作者: Ouchi;M.;Sakue;J.
• 通讯作者: J.

水セメント比と練り混ぜ方法が外力による自己充填モルタルの流動性変化に及ぼす影響

水灰比及搅拌方式对外力作用对自填充砂浆流动度变化的影响

• 发表时间: 2008
• 期刊: 土木学会第63回年次学術講演会概要集
• 作者: 中山知大;大内雅博
• 通讯作者: 大内雅博

細骨材の特性が高性能AE減水剤の分散効果に与える影響

细骨料特性对高性能AE减水剂分散效果的影响

• 发表时间: 2007
• 作者: Kita;R.;中山 知大;前田 恵佑
• 通讯作者: 前田 恵佑