Experimental Study on Pulsatile Flow of Concrete Flowing in Pipe

管内混凝土脉动流动试验研究

基本信息

批准号：
05555119
负责人：
HASHIMOTO Chikanori
金额：
$ 2.5万
依托单位：
Gunma University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research (B)
财政年份：
1993
资助国家：
日本
起止时间：
1993 至 1994
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-05555119/
关键词：
Super-flowable concrete Concrete pump Visualizaiton technique Pulsatile flow of concrete flowing in pipe Consistency Similarity Segregation Pumpability 管内流動超流動コンクリートスランプフロー試験 Lフロー試験 Vロート試験

项目摘要

A pulsatile flow of concrete flowing in pipe will adversely affect the property of the fresh concrete after being pumped as well as the pumping pipe itself. In addition, the noise resulting from the pulsating concrete flow in pipe might exceed an acceptable level from environmental points of view in the job site.This research project has been conducted to develop a novel system for pumping concrete with a minimizing degree of the pulsation in the pipe. A pumping devise designed on a small scale has two hydraulic cylinders : one for a main stream and the other for a supplemental stream, respectively, that permit to arrange the pulsation of respective stream with arbitrary levels. A visualization technique was employed to determine satisfactory levels of the pulsation of the supplemental stream that resulted in minimizing the pulsatile flow of concrete flowing through the main pipe after being combined with the supplemental stream.This research concludes that pumping concrete could be operated without causing an adverse pulsation through the pipe by arranging the pulsation levels of the supplemental stream with the main flow of a certain level of the pulsation. Also, it was found that the content of coarse aggregate per unit volume in concrete influenced the manner of pulsating flow of the concrete in pipe.

管道内流动的混凝土脉动流会对泵送后的新拌混凝土以及泵送管道本身的性能产生不利影响。此外，从工作现场的环境角度来看，管道中脉动混凝土流产生的噪音可能会超出可接受的水平。该研究项目的目的是开发一种新颖的泵送混凝土系统，最大限度地减少管道中的脉动程度。管道。小型设计的泵装置具有两个液压缸：一个用于主流，另一个用于补充流，允许以任意水平安排相应流的脉动。采用可视化技术来确定补充流脉动的令人满意的水平，从而最大限度地减少与补充流合并后流经主管的混凝土的脉动流。这项研究的结论是，泵送混凝土可以在不引起任何影响的情况下进行操作。通过将补充流的脉动水平与具有一定脉动水平的主流布置在一起来消除通过管道的不利脉动。此外，还发现混凝土中单位体积粗骨料的含量影响管道中混凝土脉动流动的方式。