An Experimental Study on the Blocking Performance Considering Construction Joint of Placement

콘크리트 이어붓기 시공에 있어 차단성에 관한 실험적 연구

This study is intended is to analyze the blocking performance with variation of the gap of bar and kinds of metal lath for construction joint when placing concrete. According to the results, passing ratio of concrete increases with increase of vibrating time. In the case of W/C 50%, when blocking concrete with bar of D10 and D20 which the gap of bar is below 200mm, or metal lath, passing ratio of concrete is below 10%, so blocking performance is favorable. In the case of W/B 30%, while concrete does not flow out without vibration at slump 21mm, concrete flows out at some degree before vibration at slump flow 65mm and then, as 5 seconds passes after first vibration, final passing ratio shows about 85~90%. When blocking concrete by bar D10 of the gap 20mm, bar D20 of the gap 10mm and metal lath, it is thought that concrete can be blocked effectively because final passing ratio is below 10%.