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๋ณด์ˆ˜์žฌ๋ฃŒ, ์นผ์Š˜ ์•Œ๋ฃจ๋ฏธ๋‚˜ ์‹œ๋ฉ˜ํŠธ, ๊ณ ์†๋„๋กœ, ๊ธฐ์ดˆ๋ฌผ์„ฑ, ๊ฒฝ์ œ์„ฑ ๋ถ„์„
GGBFS, self-healing, sea water, ultrasonic pulse velocity, brucite

  • 1. ์„œ ๋ก 

  • 2. ์žฌ๋ฃŒ ๋ฐ ์‹คํ—˜๊ณ„ํš

  • 3. ๊ฒฐ๊ณผ ๋ฐ ํ† ์˜

  •   3.1 ์ดˆ์ŒํŒŒ ์†๋„

  •   3.2 SEM

  • 4. ๊ฒฐ ๋ก 

1. ์„œ    ๋ก 

์ฝ˜ํฌ๋ฆฌํŠธ๋Š” ๋‹ค์–‘ํ•œ ํ™˜๊ฒฝ์—์„œ ์‚ฌ์šฉ๋˜๊ณ  ์žˆ๋Š” ๊ฑด์„ค์žฌ๋ฃŒ์ด๋‹ค. ์ฝ˜ํฌ๋ฆฌํŠธ๋Š” ์ทจ์„ฑ ์žฌ๋ฃŒ๋กœ ํฐ ์••์ถ•๊ฐ•๋„๋ฅผ ๊ฐ€์ง€์ง€๋งŒ ๊ฑด์กฐ์ˆ˜์ถ•, ์ˆ˜ํ™”์—ด, ๊ท ์—ด ๋“ฑ์œผ๋กœ ์ธํ•ด ๋ฐœ์ƒ๋˜๋Š” ๊ท ์—ด ๋“ฑ์— ์ทจ์•ฝํ•˜๋‹ค. ํŠนํžˆ ์ฝ˜ํฌ๋ฆฌํŠธ์— ๋ฐœ์ƒํ•˜๋Š” ๊ท ์—ด์€ ๊ตฌ์กฐ๋ฌผ์˜ ์‚ฌ์šฉ์„ฑ๊ณผ ๋‚ด๊ตฌ์„ฑ์— ์ค‘์š”ํ•œ ์˜ํ–ฅ์„ ๋ฏธ์น˜๊ณ  ์ด๋Š” ๊ตฌ์กฐ๋ฌผ ์ „์ฒด์˜ ์•ˆ์ •์„ฑ์—๋„ ์˜ํ–ฅ์„ ๋ฏธ์นœ๋‹ค. ๋”ฐ๋ผ์„œ ๊ท ์—ด์˜ ๋ฐœ์ƒ ์–ต์ œ์™€ ๋ณด์ˆ˜๋Š” ์ค‘์š”ํ•œ ๊ด€๋ฆฌ ์š”์ธ ์ค‘ ํ•˜๋‚˜๋ผ๊ณ  ํ•  ์ˆ˜ ์žˆ๋‹ค. ์ง€๋‚œ ์ˆ˜ ๋…„ ๋™์•ˆ ๋งŽ์€ ์—ฐ๊ตฌ์ž๋“ค์€ ์ฝ˜ํฌ๋ฆฌํŠธ์— ๋ฐœ์ƒํ•˜๋Š” ๊ท ์—ด์— ๋Œ€ํ•œ ์—ฐ๊ตฌ๋ฅผ ์ˆ˜ํ–‰ํ•˜์˜€๋‹ค. ๊ทธ์ค‘์—์„œ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ์ž๊ธฐ์น˜์œ (self-healing)์— ๋Œ€ํ•œ ์—ฐ๊ตฌ๋„ ์ƒ๋‹นํžˆ ๋งŽ์ด ์ด๋ฃจ์–ด์กŒ๋‹ค. ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ์ž๊ธฐ์น˜์œ ์— ๋Œ€ํ•œ ํšจ๊ณผ์™€ ๋ฐœ์ƒ์›์ธ, ์ธก์ • ๋ฐฉ๋ฒ• ๋“ฑ์— ๋Œ€ํ•œ ๋‹ค์–‘ํ•œ ์—ฐ๊ตฌ๊ฒฐ๊ณผ๋“ค์ด ์ œ์‹œ๋˜์—ˆ๋‹ค.1-23) ๋˜ํ•œ ์ž๊ธฐ์น˜์œ ๋ฅผ ์—ฐ๊ตฌํ•˜๋Š” ์ฝ˜ํฌ๋ฆฌํŠธ๋„ ๊ธฐ์กด์˜ ๋ณดํ†ต ํฌํ‹€๋žœ๋“œ ์‹œ๋ฉ˜ํŠธ(ordinary Portland Cement: OPC)์—์„œ ์ž๊ธฐ์ถฉ์ „,9) ECC,3,4) ๊ณ ๊ฐ•๋„5) ๋“ฑ์œผ๋กœ ํ™•๋Œ€๋˜๊ณ  ์žˆ๋‹ค.

๊ธฐ์กด์˜ ์ฝ˜ํฌ๋ฆฌํŠธ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ์ธก์ •ํ•˜๊ธฐ ์œ„ํ•œ ๋ฐฉ๋ฒ•์œผ๋กœ๋Š” ํœจ ๋˜๋Š” ํ• ๋ ฌ ๊ฐ•๋„, ํˆฌ์ˆ˜์„ฑ๋Šฅ, ์—ผํ™”์ด์˜จ ์นจํˆฌ ํŠน์„ฑ, ์ดˆ์ŒํŒŒ ์†๋„, ๊ท ์—ด ํญ์˜ ์ธก์ • ๋“ฑ์ด ์žˆ์—ˆ๋‹ค.1,2) ์ด๋Ÿฌํ•œ ์ธก์ • ๋ฐฉ๋ฒ•์„ ํ†ตํ•ด ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ์ž๊ธฐ์น˜์œ  ํŠน์„ฑ์„ ํŒŒ์•…ํ•˜๊ณ , ์ž๊ธฐ์น˜์œ  ๋Šฅ๋ ฅ์„ ์ธก์ •ํ•˜์˜€๋‹ค. ๋งŽ์€ ์—ฐ๊ตฌ์ž๋“ค์ด ๋‹ค์–‘ํ•œ ๋ฐฉ๋ฒ•์œผ๋กœ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ์ธก์ •ํ•˜๊ธฐ ์œ„ํ•ด ์—ฌ๋Ÿฌ ๋ฐฉ๋ฒ•๋“ค์„ ์‚ฌ์šฉํ•˜๊ณ  ์žˆ๋‹ค. ์ด ์ค‘์—์„œ ์ดˆ์ŒํŒŒ๋Š” ๊ธฐ๊ธฐ์˜ ๊ตฌ์„ฑ์ด ๋‹จ์ˆœํ•˜๊ณ , ํ˜„์žฌ๊นŒ์ง€ ๊ด‘๋ฒ”์œ„ํ•˜๊ฒŒ ์‚ฌ์šฉ๋˜์–ด์˜จ ์ธก์ •๋ฒ•์œผ๋กœ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ์ธก์ •ํ•˜๋Š” ์—ฐ๊ตฌ์—๋„ ์‚ฌ์šฉ๋˜๊ณ  ์žˆ๋‹ค.6-9) ๋˜ํ•œ ๊ธฐ์กด์˜ OPC์—์„œ ๊ณ ๋กœ์Šฌ๋ž˜๊ทธ ๋ฏธ๋ถ„๋ง, ํ”Œ๋ผ์ด์• ์‹œ, ๋ฉ”ํƒ€์นด์˜ฌ๋ฆฐ ๋“ฑ์„ ๋‹จ๋… ๋˜๋Š” ๋‹ค์ค‘ ํ˜ผํ•ฉํ•œ ์‹œ๋ฉ˜ํŠธ12,16) ๋˜๋Š” ํŒฝ์ฐฝ์žฌ14) ๋“ฑ์˜ ํ˜ผํ™”์ œ๋ฅผ ์‚ฌ์šฉํ•œ ์‹œ๋ฉ˜ํŠธ, ๋ฐ•ํ…Œ๋ฆฌ์•„10) ๋˜๋Š” ์น˜์œ ๋ฌผ์งˆ์„ ํ•จ์œ ํ•œ ์บก์Š,13,15) ์ „๊ธฐํ™”ํ•™์  ๋ฐฉ๋ฒ•11) ๋“ฑ์„ ์‚ฌ์šฉํ•œ ์ž๊ธฐ์น˜์œ  ์ฝ˜ํฌ๋ฆฌํŠธ์— ๋Œ€ํ•œ ์—ฐ๊ตฌ๋„ ์žˆ์—ˆ๋‹ค. ํ˜„์žฌ๊นŒ์ง€์˜ ์ž๊ธฐ์น˜์œ  ์—ฐ๊ตฌ์—์„œ ๊ท ์—ด์ด ๋…ธ์ถœ๋˜๋Š” ํ™˜๊ฒฝ ์กฐ๊ฑด์€ ์ฃผ๋กœ ์ˆ˜์ค‘๊ณผ ๊ณต๊ธฐ ์ค‘ ๋…ธ์ถœํ™˜๊ฒฝ,17,18) ๊ฑด์Šต ๋ฐ˜๋ณต ํ™˜๊ฒฝ,19-21) ๋™๊ฒฐ์œตํ•ด ํ™˜๊ฒฝ,8,22) ์—ฌ๋Ÿฌ ์˜จ๋„์กฐ๊ฑด23) ๋“ฑ์˜ ๋‹ค์–‘ํ•œ ์กฐ๊ฑด์—์„œ ์‹œํ—˜์ฒด์— ๋Œ€ํ•œ ์ž๊ธฐ์น˜์œ  ํŠน์„ฑ์„ ์—ฐ๊ตฌํ•˜๊ณ  ์žˆ๋‹ค.

๊ทธ๋Ÿฌ๋‚˜ ์ƒ๋Œ€์ ์œผ๋กœ ํ•ด์ˆ˜ํ™˜๊ฒฝ์— ๋Œ€ํ•œ ์—ฐ๊ตฌ๋Š” ๋ฏธํกํ•˜๋‹ค. ๊ธฐ์กด์˜ ์ž๊ธฐ์น˜์œ  ์—ฐ๊ตฌ๋Š” ๋Œ€๋ถ€๋ถ„ ๋‹ด์ˆ˜ ํ™˜๊ฒฝ์—์„œ ์ด๋ฃจ์–ด์กŒ๋‹ค. ํ•ด์ˆ˜ ํ™˜๊ฒฝ์€ ๋‹ด์ˆ˜์™€ ๋‹ฌ๋ฆฌ ๋‹ค์–‘ํ•œ ๋ฏธ์ƒ๋ฌผ, ์—ผํ™”์ด์˜จ ๊ทธ๋ฆฌ๊ณ  ์—ฌ๋Ÿฌ ๊ฐ€์ง€ ๋ฌด๊ธฐ๋ฌผ์งˆ ๋“ฑ์˜ ํšจ๊ณผ๋ฅผ ๊ณ ๋ คํ•˜์—ฌ์•ผ ํ•œ๋‹ค. ์ด๋Ÿฌํ•œ ์„ฑ๋ถ„๋“ค์€ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๋‚ด๊ตฌ์„ฑ์— ๋‹ค์–‘ํ•œ ํšจ๊ณผ๋ฅผ ๋‚˜ํƒ€๋‚ธ๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ ๊ทธ ํšจ๊ณผ๋Š” ์•„์ง ๋ช…ํ™•ํ•˜๊ฒŒ ๋ฐํ˜€์ง€์ง€ ์•Š์•˜๊ณ , ํ˜„์žฌ์—๋„ ๊ณ„์† ์—ฐ๊ตฌ ์ค‘์ด๋‹ค. ํ•ด์ˆ˜ ๋˜๋Š” ํ•ด์–‘ ํ™˜๊ฒฝ์— ๊ฑด์„ค๋˜๋Š” ์ฝ˜ํฌ๋ฆฌํŠธ ๊ตฌ์กฐ๋ฌผ์€ ํ•ดํ’, ํŒŒ๋„, ์—ผ๋ถ„ ๋“ฑ์˜ ๋งŽ์€ ์—ดํ™” ์š”์ธ์— ์˜ํ•ด ๋‚ด๊ตฌ์„ฑ์— ๋Œ€ํ•œ ๊ด€๋ฆฌ์™€ ์ฃผ์˜๊ฐ€ ๋”์šฑ ํ•„์š”ํ•˜๋‹ค. ํ•ด์–‘์˜ ๊ฐœ๋ฐœ์— ๋”ฐ๋ฅธ ๋‹ค์–‘ํ•œ ๊ตฌ์กฐ๋ฌผ์ด ๊ฑด์„ค๋˜๊ณ , ์—ฌ๊ธฐ์— ์ฝ˜ํฌ๋ฆฌํŠธ๊ฐ€ ๊ฑด์„ค์žฌ๋ฃŒ๋กœ ์‚ฌ์šฉ๋˜๋Š” ๋™์•ˆ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ํ•ด์–‘ ํ™˜๊ฒฝ์—์„œ์˜ ์—ดํ™”์™€ ์ฝ˜ํฌ๋ฆฌํŠธ ๊ตฌ์กฐ๋ฌผ์˜ ์ทจ์•ฝ์  ์ค‘์— ํ•˜๋‚˜์ธ ๊ท ์—ด์— ๋Œ€ํ•œ ๊ด€๋ฆฌ, ๋ณด์ˆ˜๊ฐ€ ํ•„์š”ํ•˜๊ฒŒ ๋œ๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ ํ•ด์ˆ˜์— ์นจ์ง€๋œ ์ฝ˜ํฌ๋ฆฌํŠธ์— ๋ฐœ์ƒ๋œ ๊ท ์—ด๊ณผ ์ž๊ธฐ์น˜์œ ์— ๋Œ€ํ•œ ์—ฐ๊ตฌ๋Š” ๋‹ด์ˆ˜์— ๋น„ํ•ด ๋ถ€์กฑํ•˜๋‹ค. ์ผ๋ถ€ ์—ฐ๊ตฌ์ž๋“ค์€ ์ธ๊ณตํ•ด์ˆ˜๋ฅผ ์ œ์กฐํ•˜์—ฌ ์ž๊ธฐ์น˜์œ  ํŠน์„ฑ์— ๊ด€ํ•œ ์—ฐ๊ตฌ๋ฅผ ์ˆ˜ํ–‰ํ•œ ์˜ˆ24)๋Š” ์žˆ์—ˆ์ง€๋งŒ, ์‹ค์ œ ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ๊ฒ€ํ† ํ•œ ์—ฐ๊ตฌ๋Š” ๋“œ๋ฌผ๋‹ค.

๋ณธ ์—ฐ๊ตฌ๋Š” ์‹œ๋ฉ˜ํŠธ์˜ ์ผ๋ถ€๋ฅผ ์Šฌ๋ž˜๊ทธ๋กœ ์น˜ํ™˜ํ•œ OPC-GGBFS ์‹œ๋ฉ˜ํŠธ์˜ ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์—์„œ์˜ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ์— ๋Œ€ํ•œ ์—ฐ๊ตฌ์ด๋‹ค. ์ด๋ฅผ ์œ„ํ•ด ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ์นจ์ง€์‹œ์ผœ ๊ฐ๊ฐ์˜ ์นจ์ง€ ํ™˜๊ฒฝ์—์„œ ์ž๊ธฐ ์น˜์œ  ํšจ๊ณผ๋ฅผ ์‚ดํŽด๋ณด๊ณ ์ž ํ•˜์˜€๋‹ค. GGBFS ์น˜ํ™˜์œจ์€ ์ง€๊ธˆ๊นŒ์ง€ ํ•ด์–‘ํ™˜๊ฒฝ์— ์‹œ๊ณต๋œ GGBFS๋ฅผ ์‚ฌ์šฉํ•œ ์ฝ˜ํฌ๋ฆฌํŠธ ๋“ค์„ ์กฐ์‚ฌํ•˜์—ฌ ์น˜ํ™˜์œจ์ด ๋งŽ์€ 10%, 20% ๊ทธ๋ฆฌ๊ณ  30% ์น˜ํ™˜์œจ์„ ์„ ์ •ํ•˜์˜€๋‹ค. ๋˜ํ•œ ํ•ด์ˆ˜์™€ ๋‹ด์ˆ˜์˜ ์นจ์ง€์‹œ ์˜จ๋„๋Š” ํ•ด์ˆ˜์— ์งโ€ค๊ฐ„์ ‘์ ์œผ๋กœ ์ ‘์ด‰ํ•˜๋Š” ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ํ™˜๊ฒฝ(๊ตฌ์กฐ๋ฌผ ์œ„์น˜, ์ˆ˜์‹ฌ ๋“ฑ)์„ ์ฐธ๊ณ ํ•˜์—ฌ ํ•ด์ˆ˜์˜ ์˜จ๋„๋ฅผ 5ยฐC, 15ยฐC ๊ทธ๋ฆฌ๊ณ  25ยฐC์˜ ์„ธ ๊ฐ€์ง€๋กœ ์„ ์ •ํ•˜์˜€๋‹ค. ์‹œํ—˜์ฒด์˜ ๊ณ ๋ ค์กฐ๊ฑด์€ ๋‹ค์Œ์˜ ์„ธ ๊ฐ€์ง€๋กœ ์š”์•ฝํ•  ์ˆ˜ ์žˆ๋‹ค.

โ€ค๋‹ด์ˆ˜(Tap-water)๊ณผ ํ•ด์ˆ˜(Sea-water)์— ์ˆ˜์ค‘ ์นจ์ง€

โ€ค5ยฐC, 15ยฐC ๊ทธ๋ฆฌ๊ณ  25ยฐC์˜ ์„ธ ๊ฐ€์ง€ ์ˆ˜์ค‘ ์นจ์ง€ ์˜จ๋„

โ€คGGBFS ์น˜ํ™˜์œจ 0, 10, 20, ๊ทธ๋ฆฌ๊ณ  30%

๊ฐ๊ฐ์˜ ๊ณ ๋ ค ์š”์†Œ์— ๋Œ€ํ•ด ํ•ด์ˆ˜์™€ ๋‹ด์ˆ˜์—์„œ์˜ ๊ณ ๋กœ์Šฌ๋ž˜๊ทธ ๋ฏธ๋ถ„๋ง์„ ์น˜ํ™˜ํ•œ ์‹œ๋ฉ˜ํŠธ์˜ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋Š” ์„ ํ–‰ ์—ฐ๊ตฌ์—์„œ ์—ฌ๋Ÿฌ ์ž๊ธฐ์น˜์œ  ์ธก์ • ๋ฐฉ๋ฒ• ์ค‘ ์ดˆ์ŒํŒŒ ์†๋„(Ultrasonic pulse velocity: UPV) ์ธก์ • ๋ฐฉ๋ฒ•์„ ์‚ฌ์šฉํ•˜์˜€๋‹ค. UPV ์ธก์ • ๋ฐฉ๋ฒ•์€ ๋น„๊ต์  ๊ธฐ๊ธฐ์™€ ์žฅ์น˜, ์ธก์ • ๋ฐฉ๋ฒ•, ๊ณ„์‚ฐ์‹์ด ๊ฐ„๋‹จํ•˜๊ณ , ๊ณผ๊ฑฐ๋ถ€ํ„ฐ UPV๋ฅผ ์‚ฌ์šฉํ•œ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๋‚ด๊ตฌ์„ฑ ๊ฒ€์‚ฌ ๋ฐฉ๋ฒ•์œผ๋กœ ์‚ฌ์šฉ๋˜์–ด ์˜ค๊ณ  ์žˆ๋‹ค. ๋˜ํ•œ ์žฌ๋ น์— ์˜ํ•œ ์‹œํ—˜์ฒด์˜ UPV ํ–ฅ์ƒ ํšจ๊ณผ์™€ ์ž๊ธฐ์น˜์œ ์— ์˜ํ•œ UPV ํ–ฅ์ƒํšจ๊ณผ๋ฅผ ๊ตฌ๋ถ„ํ•˜๊ณ ์ž, ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด์™€ ๊ท ์—ด์„ ๋ฐœ์ƒํ•œ ์‹œํ—˜์ฒด๋ฅผ ๋™์ผํ•œ ์กฐ๊ฑด์—์„œ ์นจ์ง€ํ•˜์—ฌ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ์™€ ์žฌ๋ น์— ์˜ํ•œ ํšจ๊ณผ๋ฅผ ๋น„๊ตํ•˜์˜€๋‹ค.

2. ์žฌ๋ฃŒ ๋ฐ ์‹คํ—˜๊ณ„ํš

๋ณธ ์—ฐ๊ตฌ์— ์‚ฌ์šฉ๋œ ๊ณ ๋กœ์Šฌ๋ž˜๊ทธ ๋ฏธ๋ถ„๋ง(GGBFS)์€ ํฌํ•ญ์˜ K์‚ฌ ์ œํ’ˆ์„ ์‚ฌ์šฉํ•˜์˜€์œผ๋ฉฐ, ๋ณดํ†ตํฌํ‹€๋žœ๋“œ ์‹œ๋ฉ˜ํŠธ(Ordinary Portland Cement: OPC)๋Š” ๊ตญ๋‚ด S์‚ฌ์˜ ์ œํ’ˆ์„ ์‚ฌ์šฉํ•˜์˜€๋‹ค. GGBFS์™€ OPC์˜ ์„ฑ๋ถ„์€ XRF ๋ถ„์„์„ ํ†ตํ•ด Table 1์— ๋‚˜ํƒ€๋‚ด์—ˆ๋‹ค.

Table 1 The properties of GGBFS and OPC

/Resources/kci/JKCI.2017.29.1.011/images/Table_CONCRETE_29_01_02_T1.jpg

์ž๊ธฐ์น˜์œ  ์‹œํ—˜์ฒด๋ฅผ ์นจ์ง€ํ•  ํ•ด์ˆ˜๋Š” ๋ถ€์‚ฐ์‹œ ํ•ด์šด๋Œ€๊ตฌ ํ•ด๋ณ€์—์„œ ์ฑ„์ทจํ•˜์˜€๋‹ค. ํ•ด์ˆ˜์˜ ๊ตฌ์„ฑ์„ฑ๋ถ„์€ ICP-AES (Inductively Coupled Plasma-Atomic Emission Spectrometry) ๋ถ„์„์„ ํ†ตํ•ด Table 2์— ๋‚˜ํƒ€๋‚ด์—ˆ๋‹ค.

Table 2 Component of sea-water and tap-water (ppm)

/Resources/kci/JKCI.2017.29.1.011/images/Table_CONCRETE_29_01_02_T2.jpg

(N.D: Not Detected)

์‹œํ—˜์ฒด๋Š” KS L 5109 ๋ฐฉ๋ฒ•์˜ ๋”ฐ๋ผ ๋ฐฐํ•ฉํ•˜์˜€๊ณ , ํŽ˜์ด์ŠคํŠธ์˜ ๋ฌผ-๊ฒฐํ•ฉ์žฌ ๋น„(W/b)๋Š” 0.5์ด๋‹ค. OPC์™€ GGBFS๋ฅผ ์ผ๋ถ€ ์น˜ํ™˜ํ•œ OPC-GGBFS ์‹œํ—˜์ฒด์˜ ์นจ์ง€ ํ™˜๊ฒฝ๊ณผ ์˜จ๋„์— ๋”ฐ๋ฅธ ์ž๊ธฐ์น˜์œ  ํŠน์„ฑ์„ ์‚ดํŽด๋ณด๊ธฐ ์œ„ํ•ด ๋‹ด์ˆ˜(TW)์™€ ํ•ด์ˆ˜(SW)๋ฅผ ์ค€๋น„ํ•˜์˜€๋‹ค. ๋˜ํ•œ ์นจ์ง€ํ•˜๋Š” ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์˜ ์˜จ๋„๋ฅผ 5ยฐC, 15ยฐC ๊ทธ๋ฆฌ๊ณ  25ยฐC์˜ ์„ธ ๊ฐ€์ง€๋กœ ํ•˜์—ฌ, ๊ฐ๊ฐ ์นจ์ง€๋œ ์‹œํ—˜์ฒด์˜ ์˜จ๋„์— ๋”ฐ๋ฅธ ์ž๊ธฐ์น˜์œ  ํŠน์„ฑ์„ ์ธก์ •ํ•˜์˜€๋‹ค. GGBFS๋Š” OPC ์ค‘๋Ÿ‰์— ๋Œ€ํ•ด 0%, 10%, 20%, ๊ทธ๋ฆฌ๊ณ  30%์˜ ๋„ค ์ข…๋ฅ˜์˜ ์น˜ํ™˜์œจ์„ ์„ ์ •ํ•˜์˜€๋‹ค.

์ดˆ์ŒํŒŒ ์ธก์ •์šฉ ๋ชฐ๋“œ๋Š” 40 ร— 40 ร— 160 mm์„ ์‚ฌ์šฉํ•˜์˜€๊ณ , ๊ท ์—ด ๋ถ€์˜ SEM ์ธก์ •์—๋„ ํ•ด๋‹น ์‹œํ—˜์ฒด๋ฅผ ์‚ฌ์šฉํ•˜์˜€๋‹ค. ๊ฐ๊ฐ์˜ ์žฌ๋ฃŒ๋ฅผ ๋ฐฐํ•ฉ ํ›„ ๋ชฐ๋“œ์— ํƒ€์„คํ•˜๊ณ  ์˜จ๋„ 23 ยฑ 2ยฐC์˜ ์ˆ˜์กฐ์— ๋ณด๊ด€ํ•œ๋‹ค. 24์‹œ๊ฐ„ ํ›„ ๋ชฐ๋“œ๋ฅผ ์ œ๊ฑฐํ•˜๊ณ  ์˜จ๋„ 23 ยฑ 2ยฐC์˜ ์ˆ˜์กฐ์— 28์ผ๊นŒ์ง€ ๋ณด๊ด€ํ•˜์˜€๋‹ค. 28์ผ ํ›„ ์‹œํ—˜์ฒด๋ฅผ ํ•ด์ˆ˜์™€ ๋‹ด์ˆ˜์— ์นจ์ง€ํ•˜์—ฌ ํ•ญ์˜จํ•ญ์Šต๊ธฐ์— 5ยฐC, 15ยฐC ๊ทธ๋ฆฌ๊ณ  25ยฐC์˜ ์˜จ๋„๋กœ ๋ณด๊ด€ํ•œ๋‹ค. ์‹œํ—˜์ฒด๋ฅผ ์นจ์ง€ํ•œ ํ•ด์ˆ˜์™€ ๋‹ด์ˆ˜๋Š” 2์ฃผ๋งˆ๋‹ค ํ•œ ๋ฒˆ์”ฉ ๊ต์ฒดํ•˜์˜€๋‹ค.

์ดˆ์ŒํŒŒ ์†๋„(ultrasonic pulse velocity: UPV)๋Š” PROSEQ-CCT4๋ฅผ ์‚ฌ์šฉํ•˜์—ฌ ๊ฐ๊ฐ์˜ ์ธก์ • ์žฌ๋ น์—์„œ ํ•ด๋‹น ์‹œํ—˜์ฒด์— ๋Œ€ํ•ด ์ธก์ •ํ•˜์˜€์œผ๋ฉฐ, 1๊ฐœ์˜ ์‹œํ—˜์ฒด์— ๋Œ€ํ•ด ์ขŒ์šฐ ์ธก์ •๋‹จ์ž๋ฅผ ์„œ๋กœ ๊ต์ฐจํ•ด๊ฐ€๋ฉฐ ์ธก์ •ํ•˜์—ฌ ๊ทธ ํ‰๊ท ๊ฐ’์„ ์‚ฌ์šฉํ•˜์˜€๋‹ค. UPV์˜ ๊ฐ’์€ ์ด์™€ ๊ฐ™์€ ๊ต์ฐจ ์ธก์ • ๋ฐฉ๋ฒ•์œผ๋กœ 3๊ฐœ ์‹œํ—˜์ฒด ํ‰๊ท ๊ฐ’์„ ์‚ฌ์šฉํ•˜์˜€๋‹ค. ์ตœ์ดˆ์˜ ์ดˆ์ŒํŒŒ๋Š” ์–‘์ƒ 28์ผ์—์„œ ์ˆ˜์กฐ์—์„œ ๊บผ๋‚ธ ์‹œํ—˜์ฒด ํ‘œ๋ฉด์˜ ๋ฌผ์„ ํก์ˆ˜์ฒœ์œผ๋กœ ๋‹ฆ์•„ ์ œ๊ฑฐํ•˜๊ณ  ์ดˆ์ŒํŒŒ๋ฅผ ์ธก์ •(/Resources/kci/JKCI.2017.29.1.011/images/PIC1213.gif)ํ•œ๋‹ค. ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด์ธ control์˜ ๊ฒฝ์šฐ ๊ทธ๋Œ€๋กœ ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ๊ฐ๊ฐ์˜ ์˜จ๋„๋ณ„๋กœ ์นจ์ง€ํ•œ๋‹ค. ์ž๊ธฐ์น˜์œ  ์ธก์ • ์‹œํ—˜์ฒด๋Š” /Resources/kci/JKCI.2017.29.1.011/images/PIC136C.gif ์ธก์ • ํ›„ 3์  ํœจ์‹œํ—˜์„ ํ†ตํ•ด ์‹œํ—˜์ฒด์˜ ์ค‘์•™๋ถ€์— ๋‹จ์ผ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ๋‹ค. ๊ท ์—ด์€ ์‹œํ—˜์ฒด์˜ ํœจ์‹œํ—˜์„ ํ†ตํ•ด ํŒŒ๊ดดํ•˜์ค‘์„ ๊ตฌํ•˜๊ณ , ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ฌ ์‹œํ—˜์ฒด์— ํ‰๊ท ํŒŒ๊ดดํ•˜์ค‘์˜ 90%๋ฅผ ์žฌํ•˜ํ•˜์—ฌ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œ์ผฐ๋‹ค.9) ๊ท ์—ด์˜ ํฌ๊ธฐ๋ฅผ ํ™•์ธํ•˜๊ณ  ์ดˆ์ŒํŒŒ๋ฅผ ์ธก์ •(/Resources/kci/JKCI.2017.29.1.011/images/PIC139C.gif)ํ•œ๋‹ค. ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด๋Š” ์•„ํฌ๋ฆด๋กœ ์ œ์ž‘ํ•œ ํ‹€์— ๋„ฃ์–ด ์นจ์ง€์ˆ˜์˜ ๊ต์ฒด์™€ UPV ์ธก์ •์‹œ ์‹œํ—˜์ฒด๊ฐ€ ์›€์ง์ด๋Š” ๊ฒƒ์„ ๋ฐฉ์ง€ํ•˜์˜€๋‹ค. Fig. 1์€ 3์  ํœจ์‹œํ—˜์„ ํ†ตํ•ด ์‹œํ—˜์ฒด์— ๋ฐœ์ƒ์‹œํ‚จ ๊ท ์—ด์˜ ์ผ๋ถ€์ด๋‹ค. ์„ ํ–‰ ์ž๊ธฐ์น˜์œ  ์—ฐ๊ตฌ์— ์˜ํ•˜๋ฉด ์ž๊ธฐ์น˜์œ ์— ์˜ํ–ฅ์„ ์ฃผ๋Š” ์—ฌ๋Ÿฌ ์š”์ธ๋“ค ์ค‘์— ๊ท ์—ด ํญ์˜ ์˜ํ–ฅ ๋Œ€ํ•ด ์–ธ๊ธ‰ํ•˜์˜€๋‹ค. ๋”ฐ๋ผ์„œ ๋ณธ ์—ฐ๊ตฌ์—์„œ๋Š” ๊ธฐ์กด์˜ ์—ฐ๊ตฌ์™€ UPV ์ธก์ •์„ ํ†ตํ•œ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ ํ™•์ธ์˜ ๋ณธ ์—ฐ๊ตฌ ๋ชฉ์ ์— ์ถฉ๋ถ„ํ•˜๋‹ค๊ณ  ํŒ๋‹จ๋˜๋Š” ๋ฒ”์œ„์—์„œ ์‹œํ—˜์ฒด์˜ ๊ท ์—ดํญ์„ 200 ยตm์ดํ•˜์ธ ์‹œํ—˜์ฒด๋“ค๋งŒ์„ ์„ ํƒํ•˜์—ฌ ์ž๊ธฐ์น˜์œ  ์‹œํ—˜์„ ์ˆ˜ํ–‰ํ•˜์˜€๋‹ค. ์ด๋Š” ๋ณธ ์—ฐ๊ตฌ์˜ ๋ชฉ์ ์ธ ์„ธ ๊ฐ€์ง€ ์˜จ๋„์˜ ํ•ด์ˆ˜์™€ ๋‹ด์ˆ˜์˜ ์นจ์ง€ํ™˜๊ฒฝ๊ณผ UPV๋ฅผ ์‚ฌ์šฉํ•œ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ์˜ ์ƒ๋Œ€์  ์ฐจ์ด์™€ ํŠน์„ฑ์„ ์—ฐ๊ตฌํ•˜๋Š” ๋ชฉ์ ์— ์ ํ•ฉํ•  ๊ฒƒ์œผ๋กœ ํŒ๋‹จํ•˜์˜€๋‹ค.

/Resources/kci/JKCI.2017.29.1.011/images/Figure_CONCRETE_29_01_02_F1.jpg

Fig. 1 Crack of specimens

์ดํ›„ ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ๊ฐ๊ฐ์˜ ์˜จ๋„๋ณ„๋กœ ์นจ์ง€๋œ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ control ์‹œํ—˜์ฒด์˜ ์นจ์ง€ ํ›„ 30์ผ(/Resources/kci/JKCI.2017.29.1.011/images/PIC13DB.gif)๊ณผ 60์ผ(/Resources/kci/JKCI.2017.29.1.011/images/PIC141B.gif)์—์„œ UPV๋ฅผ ์ธก์ •ํ•˜๊ณ , ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด์— ๋Œ€ํ•ด์„œ ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ์นจ์ง€ ํ›„ 30์ผ(/Resources/kci/JKCI.2017.29.1.011/images/PIC1489.gif)๊ณผ 60์ผ(/Resources/kci/JKCI.2017.29.1.011/images/PIC1507.gif)์—์„œ UPV๋ฅผ ์ธก์ •ํ•œ๋‹ค.

3. ๊ฒฐ๊ณผ ๋ฐ ํ† ์˜

3.1 ์ดˆ์ŒํŒŒ ์†๋„

Table 3์€ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด(control)๋ฅผ 5ยฐC, 15ยฐC ๊ทธ๋ฆฌ๊ณ  25ยฐC์˜ ์„ธ ๊ฐ€์ง€ ์˜จ๋„์—์„œ ์ผ์ •๊ธฐ๊ฐ„ ๋™์•ˆ ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ๋’ค ์ธก์ •ํ•œ UPV ๊ฒฐ๊ณผ์ด๋‹ค. control ์‹œํ—˜์ฒด์˜ ๊ฒฝ์šฐ ๋ชจ๋“  GGBFS ์น˜ํ™˜์œจ์—์„œ ์žฌ๋ น์ด ์ฆ๊ฐ€ํ•˜๋ฉด UPV๋„ ์ฆ๊ฐ€ํ•˜์˜€๋‹ค. ์ด๋Š” ์‹œ๊ฐ„์— ๋”ฐ๋ฅธ ๋ฏธ์ˆ˜ํ™” ๊ฒฐํ•ฉ์žฌ์˜ ์ˆ˜ํ™”๋ฐ˜์‘์— ๋”ฐ๋ฅธ ์žฅ๊ธฐ๊ฐ•๋„ ์ฆ๊ฐ€ํ˜„์ƒ์ด๋‹ค.

Table 3 UPV of control specimens (un-cracked)

/Resources/kci/JKCI.2017.29.1.011/images/Table_CONCRETE_29_01_02_T3.jpg

(N.D: Not Detected)

Table 4๋Š” ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด๋ฅผ ๊ฐ๊ฐ์˜ ์˜จ๋„๋ณ„๋กœ ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ๋‹ค์Œ ์นจ์ง€ 30์ผ๊ณผ 60์ผ์—์„œ ์ธก์ •ํ•œ UPV ๊ฐ’์„ ๋‚˜ํƒ€๋‚ธ ๊ฒƒ์ด๋‹ค. ์žฌ๋ น 28์ผ์—์„œ ์ธก์ •ํ•œ ์ดˆ๊ธฐ UPV ์ธก์ • ํ›„ 3์  ํœจ ์‹œํ—˜์œผ๋กœ ์‹œํ—˜์ฒด์— ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ํ›„ ์ธก์ •ํ•œ UPV (/Resources/kci/JKCI.2017.29.1.011/images/PIC1556.gif)๊ฐ€ ๊ฐ์†Œํ•œ ๊ฒƒ์„ ํ™•์ธํ•  ์ˆ˜ ์žˆ๋‹ค. ์นจ์ง€ ํ›„ 30์ผ์—์„œ ์ธก์ •ํ•œ UPV30H ๊ฐ’๋“ค ์ค‘ ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ 0% GGBFS ์‹œํ—˜์ฒด(OPC 100%)๋ฅผ ์ œ์™ธํ•˜๊ณ ๋Š” ๋ชจ๋“  ์‹œํ—˜์ฒด๊ฐ€ ์ดˆ๊ธฐ /Resources/kci/JKCI.2017.29.1.011/images/PIC15B5.gif์™€ ๋น„์Šทํ•˜๊ฑฐ๋‚˜ ๋ฏธ๋ฏธํ•˜๊ฒŒ ์ฆ๊ฐ€ํ•˜์˜€๋‹ค. ๋”ฐ๋ผ์„œ ๊ท ์—ด ๋ฐœ์ƒ ํ›„ ์˜จ๋„๊ฐ€ ์„œ๋กœ ๋‹ค๋ฅธ ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ๋ชจ๋“  ์‹œํ—˜์ฒด๋Š” UPV๊ฐ€ ์ฆ๊ฐ€ํ•˜๋Š” ๊ฒฝํ–ฅ์„ ๋ณด์˜€๋‹ค.

Table 4 UPV of cracked specimens

/Resources/kci/JKCI.2017.29.1.011/images/Table_CONCRETE_29_01_02_T4.jpg

๋‹ค์–‘ํ•œ ํ˜ผํ™”์žฌ๋ฅผ ์‚ฌ์šฉํ•œ ์‹œํ—˜์ฒด์— ๋Œ€ํ•ด UPV๋ฅผ ์‚ฌ์šฉํ•œ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ์—ฐ๊ตฌํ•œ ์„ ํ–‰์—ฐ๊ตฌ์ž๋“ค์˜ ๊ฒฐ๊ณผ๋“ค์„ ๋ณด๋ฉด Sahmaran et al.9)๊ฐ€ ์ˆ˜ํ–‰ํ•œ ํ”Œ๋ผ์ด์• ์‹œ(fly ash, FA)๋ฅผ OPC ์ค‘๋Ÿ‰์— ๋Œ€ํ•ด 0, 35, 55% ์น˜ํ™˜ํ•œ ๋Œ€๋Ÿ‰์น˜ํ™˜ ํ”Œ๋ผ์ด์• ์‹œ ์ฝ˜ํฌ๋ฆฌํŠธ(HVFA-SCC)๋กœ ๋‹ด์ˆ˜์— ์นจ์ง€ํ•œ ์ž๊ธฐ์น˜์œ  ์‹œํ—˜ ์—ฐ๊ตฌ์—์„œ FA ์น˜ํ™˜์œจ์ด ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ UPV๊ฐ€ ๊ฐ์†Œํ•˜์˜€๋‹ค. ๋˜ํ•œ ๊ท ์—ด ๋ฐœ์ƒ ํ›„ 15์ผ๊ณผ 30์ผ ๊ฒฝ๊ณผ ํ›„ ์ธก์ •ํ•œ UPV ๊ฒฐ๊ณผ์—์„œ UPV๊ฐ€ ์ ์ฐจ ์ฆ๊ฐ€ํ•˜์˜€๋‹ค. Zhong et al.7) ๋“ฑ์€ UPV ์ธก์ •์„ ํ†ตํ•œ ๊ท ์—ด ๋ฐœ์ƒ ์ „ ํ›„์˜ UPV ๋ณ€ํ™”๋ฅผ ์ธก์ •ํ•˜์˜€๋‹ค. ์ผ์ •๊ธฐ๊ฐ„ ์ˆ˜์ค‘ ์นจ์ง€ ํ›„ UPV ์ฆ๊ฐ€๋ฅผ ํ†ตํ•ด ๊ท ์—ด ์น˜์œ  ํšจ๊ณผ๋ฅผ ํ™•์ธํ•˜์˜€๋‹ค. ์„ ํ–‰์—ฐ๊ตฌ๊ฒฐ๊ณผ1-3,7)๋“ค์—์„œ ์ˆ˜์ค‘์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด๋“ค์€ ์นจ์ง€ ๊ธฐ๊ฐ„์ด ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ UPV๋„ ์ฆ๊ฐ€ํ•˜๋Š” ๊ฒฐ๊ณผ๋ฅผ ๋‚˜ํƒ€๋‚ด์—ˆ์œผ๋ฉฐ, ํ•ด์ˆ˜์™€ ๋‹ด์ˆ˜์— ์นจ์ง€ํ•œ ๋ณธ ์—ฐ๊ตฌ์˜ UPV ๊ฒฝํ–ฅ๋„ ์œ ์‚ฌํ•˜๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋‹ค.

์„ธ ๊ฐ€์ง€ ์˜จ๋„์— ๋”ฐ๋ฅธ ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ GGBFS์˜ ์น˜ํ™˜์œจ์ด ๋‹ค๋ฅธ ์‹œํ—˜์ฒด์˜ 30์ผ๊ณผ 60์ผ์— ์ธก์ •ํ•œ UPV ๊ฐ’๋“ค์˜ ๋น„์œจ์ธ UPV ์ฆ๊ฐ€์œจ์„ ํ†ตํ•ด ๊ทธ ํŠน์„ฑ์„ ์‚ดํŽด๋ณด์•˜๋‹ค. ์ดˆ๊ธฐ ์ธก์ •, ์นจ์ง€ 30์ผ ๊ทธ๋ฆฌ๊ณ  ์นจ์ง€ 60์ผ์—์„œ ์ธก์ •ํ•œ UPV ๊ฐ’์„ ํ†ตํ•ด ์นจ์ง€ ๊ธฐ๊ฐ„์— ๋”ฐ๋ฅธ ์ƒ๋Œ€์ ์ธ ์ž๊ธฐ์น˜์œ ํšจ๊ณผ๋ฅผ ์‚ดํŽด๋ณด๊ณ ์ž ๊ฐ๊ฐ์˜ ์นจ์ง€ ๊ธฐ๊ฐ„์— ๋”ฐ๋ฅธ UPV ์ฆ๊ฐ€์œจ์€ ๋‹ค์Œ ์‹์œผ๋กœ ๊ณ„์‚ฐํ•˜์˜€๋‹ค.

Control specimens (un-cracked specimens)

/Resources/kci/JKCI.2017.29.1.011/images/PIC1662.gif (1-1)

/Resources/kci/JKCI.2017.29.1.011/images/PIC16D0.gif (1-2)

Cracked specimens

/Resources/kci/JKCI.2017.29.1.011/images/PIC172F.gif (1-3)

/Resources/kci/JKCI.2017.29.1.011/images/PIC178E.gif (1-4)

์‹ (1-1)์€ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ control ์‹œํ—˜์ฒด์˜ ์ตœ์ดˆ ์ธก์ •ํ•œ UPV (/Resources/kci/JKCI.2017.29.1.011/images/PIC17BE.gif)์— ๋Œ€ํ•œ ์นจ์ง€ 30์ผ ํ›„์˜ UPV ์ฆ๊ฐ€์œจ(/Resources/kci/JKCI.2017.29.1.011/images/PIC17FD.gif)์ด๋ฉฐ, ์‹ (1-2)๋Š” ์นจ์ง€ 30์ผ์—์„œ ์ธก์ •ํ•œ UPV(/Resources/kci/JKCI.2017.29.1.011/images/PIC181E.gif)์— ๋Œ€ํ•œ ์นจ์ง€ 60์ผ์—์„œ ์ธก์ •ํ•œ UPV (/Resources/kci/JKCI.2017.29.1.011/images/PIC183E.gif)์˜ ์ฆ๊ฐ€์œจ(/Resources/kci/JKCI.2017.29.1.011/images/PIC185E.gif)์ด๋‹ค. ๋˜ํ•œ ์‹ (1-3)์€ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด(cracked specimens)์˜ ๊ท ์—ด๋ฐœ์ƒ ์งํ›„ ์ธก์ •ํ•œ UPV (/Resources/kci/JKCI.2017.29.1.011/images/PIC189E.gif)์— ๋Œ€ํ•œ ์นจ์ง€ 30์ผ ํ›„์˜ UPV ์ฆ๊ฐ€์œจ(/Resources/kci/JKCI.2017.29.1.011/images/PIC18DD.gif)์ด๋ฉฐ, ์‹ (1-4)๋Š” ์นจ์ง€ 30์ผ(/Resources/kci/JKCI.2017.29.1.011/images/PIC191D.gif)์— ๋Œ€ํ•œ ์นจ์ง€ 60์ผ(/Resources/kci/JKCI.2017.29.1.011/images/PIC195C.gif)์—์„œ ์ธก์ •ํ•œ UPV์˜ ์ฆ๊ฐ€์œจ(/Resources/kci/JKCI.2017.29.1.011/images/PIC197C.gif)์ด๋‹ค.

Fig. 2๋Š” ๋‹ด์ˆ˜์— ์นจ์ง€ํ•œ ๊ท ์—ด์ด ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด์™€ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด์˜ UPV ์ฆ๊ฐ€์œจ์„ ์‹ (1-1)~(1-4)์— ๋”ฐ๋ผ ๊ณ„์‚ฐํ•œ ๊ฒฐ๊ณผ๋ฅผ ๋‚˜ํƒ€๋‚ธ ๊ฒƒ์ด๋‹ค. Fig. 2(a)์˜ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด๋Š” ๋‹ด์ˆ˜์— ์นจ์ง€ ํ›„ 30์ผ๊นŒ์ง€์˜ UPV ์ฆ๊ฐ€์œจ(/Resources/kci/JKCI.2017.29.1.011/images/PIC19DB.gif)์ด ์นจ์ง€ 30์ผ์—์„œ 60์ผ์‚ฌ์ด์˜ ์ฆ๊ฐ€์œจ(/Resources/kci/JKCI.2017.29.1.011/images/PIC19FB.gif)๋ณด๋‹ค ํฌ๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ํŠนํžˆ, GGBFS์˜ ์น˜ํ™˜์œจ์ด 10%์—์„œ 30%๋กœ ์ฆ๊ฐ€ํ• ์ˆ˜๋ก /Resources/kci/JKCI.2017.29.1.011/images/PIC1A3B.gif์™€ /Resources/kci/JKCI.2017.29.1.011/images/PIC1A5B.gif์˜ ์ฐจ์ด๋Š” ํ™•์—ฐํžˆ ๋‚˜ํƒ€๋‚˜๊ณ  ์žˆ์—ˆ๋‹ค. ์นจ์ง€ ์˜จ๋„์— ๋”ฐ๋ฅธ UPV์˜ ๋ณ€ํ™” ํŠน์„ฑ์€ ๋ฏธ๋ฏธํ•˜์—ฌ ํฐ ์ฐจ์ด๋ฅผ ํ™•์ธํ•˜๊ธฐ ์–ด๋ ค์› ์ง€๋งŒ, 30% GGBFS ์น˜ํ™˜์œจ์˜ ์‹œํ—˜์ฒด๋Š” 25ยฐC์˜ ์นจ์ง€์˜จ๋„์—์„œ ์ƒ๋Œ€์ ์œผ๋กœ ๋‹ค๋ฅธ ์˜จ๋„์™€ ๋น„๊ตํ•˜์—ฌ UPV ์ฆ๊ฐ€์œจ์ด ๋†’๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ๋‹ด์ˆ˜์— ์นจ์ง€ํ•œ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด์˜ ๊ฒฝ์šฐ(Fig. 2(b)) ์นจ์ง€ 30์ผ๊นŒ์ง€์˜ UPV ์ฆ๊ฐ€์œจ(/Resources/kci/JKCI.2017.29.1.011/images/PIC1A7B.gif)์ด ์นจ์ง€ 30์ผ์—์„œ 60์ผ ์‚ฌ์ด์˜ ์ฆ๊ฐ€์œจ(/Resources/kci/JKCI.2017.29.1.011/images/PIC1ABB.gif)๋ณด๋‹ค ํ™•์—ฐํ•˜๊ฒŒ ํฌ๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด(Fig. 2(b))๊ฐ€ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด(Fig. 2(a))๋ณด๋‹ค ์ƒ๋Œ€์ ์œผ๋กœ ๋” ํฐ /Resources/kci/JKCI.2017.29.1.011/images/PIC1ACB.gif์™€ /Resources/kci/JKCI.2017.29.1.011/images/PIC1AEC.gif์‚ฌ์ด์˜ ์ฐจ์ด๋ฅผ ๋‚˜ํƒ€๋‚ด์—ˆ๋‹ค. ์ด๋Š” ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด๋“ค์˜ ์นจ์ง€ ํ›„ 30์ผ ๋™์•ˆ UPV ์ฆ๊ฐ€์œจ์ด control ์‹œํ—˜์ฒด ๋ณด๋‹ค ํฌ๊ฒŒ ๋‚˜ํƒ€๋‚œ ๊ฒƒ์€ ๊ท ์—ด๋กœ ์ธํ•ด ๋‹ด์ˆ˜์™€ ์ ‘์ด‰ํ•˜๋Š” ๋ฉด์ ์ด ์ฆ๊ฐ€ํ•˜๊ณ , ๊ท ์—ด๋ฉด์˜ ์ผ๋ถ€์— ๋‚จ์•„ ์žˆ๋˜ ๋ฏธ์ˆ˜ํ™” GGBFS ๋˜๋Š” OPC์˜ ์žฌ์ˆ˜ํ™”(re-hydration)์™€ ์ž๊ธฐ์น˜์œ  ๋ฌผ์งˆ์˜ ์„ฑ์žฅ(recrystalized)์œผ๋กœ ์ธํ•ด ๊ท ์—ด๋ฉด ๋‹ซํž˜์ด ๋นจ๋ผ์ ธ ์ƒ๋Œ€์ ์œผ๋กœ UPV ์ฆ๊ฐ€์œจ์ด ํฐ ๊ฒƒ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค.25) ํŠนํžˆ GGBFS์˜ ์น˜ํ™˜์œจ์ด 30%์ธ ์‹œํ—˜์ฒด๋“ค์˜ UPV ๋ณ€ํ™”์œจ์ด ๊ฐ€์žฅ ํฌ๊ฒŒ ๋‚˜ํƒ€๋‚˜๊ณ  ์žˆ๋Š”๋ฐ, ์ด๋Š” GGBFS์˜ ์น˜ํ™˜์œจ์ด ๋†’์€ ๋งŒํผ ๋ฏธ์ˆ˜ํ™” GGBFS์˜ ์–‘์ด ์ƒ๋Œ€์ ์œผ๋กœ ๋งŽ์•„์„œ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๊ฐ€ ํ–ฅ์ƒ๋˜์—ˆ๊ธฐ ๋•Œ๋ฌธ์ด๋‹ค.

/Resources/kci/JKCI.2017.29.1.011/images/Figure_CONCRETE_29_01_02_F2.jpg

Fig. 2 Relative change rate of UPV for specimens immersed in tap water

Fig. 2(b)์—์„œ ์นจ์ง€ ์˜จ๋„์— ๋”ฐ๋ฅธ UPV ์ฆ๊ฐ€์œจ ํŠน์„ฑ์„ ์‚ดํŽด๋ณด๋ฉด, 25ยฐC > 15ยฐC > 5ยฐC ์ˆœ์„œ๋กœ UPV ์ฆ๊ฐ€์œจ์ด ํฌ๊ฒŒ ๋‚˜ํƒ€๋‚˜๊ณ  ์žˆ๋‹ค. ์ด๋Š” ์‹œํ—˜์ฒด๋ฅผ ์นจ์ง€ํ•œ ๋‹ด์ˆ˜์˜ ์˜จ๋„๊ฐ€ ๋†’์„์ˆ˜๋ก ๋ฏธ์ˆ˜ํ™” ์ž…์ž๋“ค์˜ ์žฌ์ˆ˜ํ™” ํšจ๊ณผ๊ฐ€ ํ–ฅ์ƒ๋˜์–ด ์ƒ๋Œ€์ ์œผ๋กœ ๋†’์€ UPV ์ฆ๊ฐ€์œจ์ด ๋‚˜ํƒ€๋‚˜๋Š” ๊ฒƒ์ด๋‹ค. Reinhardt and Jooss23)์˜ ์—ฐ๊ตฌ์—์„œ ๋‹ด์ˆ˜์˜ ์˜จ๋„๊ฐ€ 20ยฐC, 50ยฐC, 80ยฐC๋กœ ์ฆ๊ฐ€ํ• ์ˆ˜๋ก ๊ท ์—ด์น˜์œ  ํšจ๊ณผ๊ฐ€ ํฌ๋‹ค๊ณ  ํ•˜์˜€๋‹ค. ๋ณธ ์—ฐ๊ตฌ์˜ ์˜จ๋„ ๋ฒ”์œ„์ธ 5ยฐC ~ 25ยฐC์˜ ์˜จ๋„์—์„œ๋„ ์˜จ๋„๊ฐ€ ๋†’์„์ˆ˜๋ก ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ์˜ ์ฐจ์ด๊ฐ€ ์žˆ์Œ์„ ํ™•์ธํ•  ์ˆ˜ ์žˆ์—ˆ๋‹ค.

Fig. 3๋Š” ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด์™€ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด์˜ UPV ์ฆ๊ฐ€์œจ์„ ๋‚˜ํƒ€๋‚ธ ๊ฒƒ์ด๋‹ค. ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด์˜ ๊ฒฝ์šฐ(Fig. 3(a)), 20% GGBFS ์น˜ํ™˜์œจ๊นŒ์ง€ ์นจ์ง€ 30์ผ๊นŒ์ง€์˜ UPV ์ฆ๊ฐ€์œจ(/Resources/kci/JKCI.2017.29.1.011/images/PIC1B2B.gif)๊ณผ ์นจ์ง€ 30์ผ์—์„œ 60์ผ์‚ฌ์ด์˜ UPV ์ฆ๊ฐ€์œจ(/Resources/kci/JKCI.2017.29.1.011/images/PIC1B4B.gif)์ด ํฐ ์ฐจ์ด๊ฐ€ ์—†์ด ๋น„์Šทํ•˜๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด์˜ ๊ฒฝ์šฐ(Fig. 3(b)), ์นจ์ง€ 30์ผ๊นŒ์ง€์˜ UPV ์ฆ๊ฐ€์œจ(/Resources/kci/JKCI.2017.29.1.011/images/PIC1B6C.gif)์ด ์นจ์ง€ 30์ผ์—์„œ 60์ผ๊นŒ์ง€์˜ ์ฆ๊ฐ€์œจ(/Resources/kci/JKCI.2017.29.1.011/images/PIC1B9C.gif)๋ณด๋‹ค ํฌ๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ์ด๋Ÿฌํ•œ ์ฆ๊ฐ€์œจ ๊ฒฝํ–ฅ์€ ๋‹ด์ˆ˜์— ์นจ์ง€ํ•œ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด์˜ UPV ์ฆ๊ฐ€์œจ ํŠน์„ฑ(Fig. 2(b))๊ณผ ์œ ์‚ฌํ•˜๋‹ค. ๋˜ํ•œ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด์˜ ๊ฒฝ์šฐ GGBFS์˜ ์น˜ํ™˜์œจ์ด ์ฆ๊ฐ€ํ• ์ˆ˜๋ก UPV ์ฆ๊ฐ€์œจ(/Resources/kci/JKCI.2017.29.1.011/images/PIC1BBC.gif)๋„ ์ฆ๊ฐ€ํ•˜์—ฌ, 30% GGBFS ์น˜ํ™˜ ์‹œํ—˜์ฒด์˜ UPV ์ฆ๊ฐ€์œจ(/Resources/kci/JKCI.2017.29.1.011/images/PIC1BDC.gif)์ด ๊ฐ€์žฅ ์ปธ๋‹ค.

๊ทธ๋Ÿฌ๋‚˜ ๋‹ด์ˆ˜์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด๋“ค๊ณผ ๋‹ฌ๋ฆฌ ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด์™€ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด ๋ชจ๋‘ ์นจ์ง€ ํ•ด์ˆ˜์˜ ์˜จ๋„์— ๋”ฐ๋ฅธ UPV ์ฆ๊ฐ€์œจ์€ ์˜จ๋„์— ๋”ฐ๋ฅธ ์ผ์ •ํ•œ ๊ฒฝํ–ฅ์„ ๋ณด์ด์ง€ ์•Š์•˜๋‹ค. ๋‹ด์ˆ˜์˜ ๊ฒฝ์šฐ ์นจ์ง€ ๋‹ด์ˆ˜์˜ ์˜จ๋„๊ฐ€ ๋†’์„์ˆ˜๋ก UPV ์ฆ๊ฐ€์œจ์ด ์ฆ๊ฐ€ํ•˜๋Š” ๊ฒฝํ–ฅ์„ ๋ณด์ด์ง€๋งŒ, ํ•ด์ˆ˜์˜ ์นจ์ง€์˜จ๋„์— ๋”ฐ๋ฅธ UPV ์ฆ๊ฐ€์œจ์€ GGBFS ์น˜ํ™˜์œจ, ๊ท ์—ด ๋ฐœ์ƒ ์œ ๋ฌด ๋“ฑ์— ๋”ฐ๋ฅธ ๋šœ๋ ทํ•œ ๊ฒฝํ–ฅ์„ฑ์„ ์ฐพ๊ธฐ ์–ด๋ ค์› ๋‹ค. ์ด๋Š” ํ•ด์ˆ˜์— ํฌํ•จ๋œ ๋‹ค์–‘ํ•œ ๋ฌด๊ธฐ๋ฌผ์งˆ๋“ค์— ์˜ํ•œ ๊ท ์—ด๋ฉด ๋˜๋Š” ์ž๊ธฐ์น˜์œ  ๋ฌผ์งˆ ์ƒ์„ฑ ๋“ฑ์— ์˜ํ–ฅ์„ ์ฃผ์–ด UPV์˜ ์ธก์ •์‹œ ์˜จ๋„์— ๋”ฐ๋ฅธ ์˜ํ–ฅ์ด ์—†๊ฑฐ๋‚˜ UPV ์ธก์ •์— ์˜ํ–ฅ์„ ๋ฏธ์น˜๋Š” ๋‹ค๋ฅธ ์›์ธ์ด ์žˆ์„ ๊ฒƒ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค.

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Fig. 3 Relative change rate of UPV for specimens immersed in sea water

๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ์นจ์ง€๋œ ์‹œํ—˜์ฒด๋“ค์˜ UPV ์ฆ๊ฐ€์œจ์„ ์‚ดํŽด๋ณธ ๊ฒฐ๊ณผ GGBFS์˜ ์น˜ํ™˜์œจ๊ณผ ์นจ์ง€ ์˜จ๋„๋Š” UPV ์ฆ๊ฐ€์— ์ผ์ • ๋ถ€๋ถ„ ์˜ํ–ฅ์„ ๋ฏธ์น˜๋Š” ๊ฒƒ์œผ๋กœ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ํŠนํžˆ GGBFS์˜ ์น˜ํ™˜์œจ์— ๋Œ€ํ•œ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ์‚ดํŽด๋ณด๋ฉด GGBFS ์น˜ํ™˜์œจ์ด ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ UPV ์ฆ๊ฐ€์œจ(/Resources/kci/JKCI.2017.29.1.011/images/PIC1C0C.gif, /Resources/kci/JKCI.2017.29.1.011/images/PIC1C4B.gif)์„ ํ†ตํ•ด ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๊ฐ€ ์ฆ๊ฐ€ํ•˜๋Š” ๊ฒƒ์„ ๋ณผ ์ˆ˜ ์žˆ๋‹ค. ์ด๋Š” OPC์˜ ์ผ๋ถ€๋ฅผ GGBFS๋กœ ์น˜ํ™˜ํ•œ ๊ฒฝ์šฐ, OPC๋ณด๋‹ค ๋‚ฎ์€ GGBFS์˜ ์ˆ˜ํ™”๋ฐ˜์‘์„ฑ์œผ๋กœ ์ธํ•ด ์žฌ๋ น์˜ ์ฆ๊ฐ€์— ๋”ฐ๋ฅธ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๊ฐ€ ์ผ์ • ๋ถ€๋ถ„ ์ง€์†๋œ๋‹ค.25) ์ด๋Ÿฌํ•œ ๊ฒฐ๊ณผ๋Š” Liu and Zuo26)์˜ GGBFS์™€ FA์˜ ์น˜ํ™˜์œจ์ด ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ ์ž๊ธฐ์น˜์œ  ๋Šฅ๋ ฅ๋„ ์ฆ๊ฐ€ํ•œ๋‹ค๋Š” ์—ฐ๊ตฌ๊ฒฐ๊ณผ์™€ Tittelboom et al.25)๋„ GGBFS์˜ ์น˜ํ™˜์ด ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ํ–ฅ์ƒ์‹œํ‚จ๋‹ค๋Š” ์—ฐ๊ตฌ๊ฒฐ๊ณผ์™€ ์œ ์‚ฌํ•œ ๊ฒฐ๊ณผ์ด๋‹ค. ํŠนํžˆ GGBFS์˜ ์น˜ํ™˜์œจ์ด ์ฆ๊ฐ€ํ• ์ˆ˜๋ก ๋ฏธ์ˆ˜ํ™” GGBFS์˜ ์–‘์ด ์ƒ๋Œ€์ ์œผ๋กœ ์ฆ๊ฐ€ํ•˜๊ณ , ์ด๋Š” ๊ท ์—ด ๋ฐœ์ƒ ํ›„ ๊ท ์—ด๋ฉด์— ๋…ธ์ถœ๋˜๋Š” ๋ฏธ์ˆ˜ํ™” GGBFS์™€ OPC์˜ ์–‘๋„ ์ฆ๊ฐ€ํ•˜๊ฒŒ ๋˜๋ฏ€๋กœ ๊ท ์—ด๋ฉด์˜ ์ž๊ธฐ์น˜์œ ํ˜„์ƒ์ด ์‹œ๊ฐ„์˜ ๊ฒฝ๊ณผ์— ๋”ฐ๋ผ ์„œ์„œํžˆ ๋ฐœ์ƒํ•œ๋‹ค.27) ๋˜ํ•œ ์˜จ๋„์— ๋”ฐ๋ฅธ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋„ ์•ž์„œ ์–ธ๊ธ‰ํ•œ Reinhardt and Jooss23)์˜ ์—ฐ๊ตฌ๊ฒฐ๊ณผ์ฒ˜๋Ÿผ ๋‹ด์ˆ˜์˜ ๊ฒฝ์šฐ์—๋Š” ์ƒ๋Œ€์ ์œผ๋กœ ๋†’์€ ์˜จ๋„์—์„œ UPV ์ฆ๊ฐ€์œจ์ด ํฌ๊ฒŒ ๋‚˜ํƒ€๋‚˜๊ณ  ์žˆ์—ˆ๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ ํ•ด์ˆ˜์—์„œ๋Š” ์˜จ๋„์— ๋”ฐ๋ฅธ ๋ช…ํ™•ํ•œ ๊ฒฝํ–ฅ์„ ํ™•์ธํ•˜๊ธฐ ์–ด๋ ค์› ๋‹ค.

Fig. 2์™€ Fig. 3์—์„œ ๋‹ด์ˆ˜, ํ•ด์ˆ˜ ๋ชจ๋‘ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด์—์„œ ์นจ์ง€ 30์ผ๊นŒ์ง€์˜ UPV ์ฆ๊ฐ€์œจ์ด ์นจ์ง€ 30์ผ์—์„œ 60์ผ๊นŒ์ง€์˜ UPV ์ฆ๊ฐ€์œจ๋ณด๋‹ค ์ƒ๋Œ€์ ์œผ๋กœ ๋†’๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ์ด๋ฅผ ํ†ตํ•ด ๊ท ์—ด์ด ๋ฐœ์ƒํ•œ ์‹œํ—˜์ฒด์˜ ์นจ์ง€ ํ›„ 30์ผ ๋™์•ˆ ๋ฏธ์ˆ˜ํ™” ์‹œ๋ฉ˜ํŠธ ๋˜๋Š” GGBFS์˜ ์ˆ˜ํ™” ์ง„ํ–‰๊ณผ ๊ท ์—ด๋ฉด์˜ ์ž๊ธฐ์น˜์œ  ๋ฌผ์งˆ์— ์ƒ์„ฑ ๋“ฑ์— ์˜ํ•œ ๊ท ์—ด๋ฉด์˜ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๊ฐ€ ์ตœ๋Œ€๋กœ ๋ฐœ์ƒํ•˜๊ณ , ์ดํ›„์—๋Š” ๊ฐ์†Œํ•˜์—ฌ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๊ฐ€ ๊ฐ์†Œํ•˜๋Š” ๊ฒƒ์ด๋‹ค. ์ด๋Š” ์„ ํ–‰ ์—ฐ๊ตฌ๊ฒฐ๊ณผ๋“ค์—์„œ ๊ท ์—ด ๋ฐœ์ƒ ํ›„ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋Š” ์นจ์ง€ ์ดˆ๊ธฐ ๋˜๋Š” ์นจ์ง€ ํ›„ ์•ฝ 30์ผ ์ „ํ›„์˜ ๊ธฐ๊ฐ„ ๋™์•ˆ ๊ฐ€์žฅ ํ™œ๋ฐœํžˆ ์ผ์–ด๋‚œ๋‹ค๋Š” ์—ฐ๊ตฌ๋“ค๊ณผ ์œ ์‚ฌํ•œ ๊ฒฐ๊ณผ๋ฅผ ๋‚˜ํƒ€๋‚ด์—ˆ๋‹ค.27-29)

์ž๊ธฐ์น˜์œ ์˜ ๊ฒฝ์šฐ, ์‹œํ—˜์ฒด์˜ ์žฌ๋ น ์ฆ๊ฐ€์— ์˜ํ•œ UPV ์ฆ๊ฐ€ํšจ๊ณผ์™€ ์ž๊ธฐ์น˜์œ ์— ์˜ํ•œ UPV ํšจ๊ณผ๋ฅผ ๊ตฌ๋ถ„ํ•˜๊ธฐ ์–ด๋ ต๋‹ค. ๋”ฐ๋ผ์„œ ๋ณธ ์—ฐ๊ตฌ์—์„œ๋Š” ๋™์ผํ•œ ๋ฐฐํ•ฉ์˜ ์‹œํ—˜์ฒด๋ฅผ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด(uncracked specimens)๊ณผ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด(cracked specimens)์œผ๋กœ ๊ตฌ๋ถ„ํ•˜์—ฌ ๋™์ผํ•œ ์กฐ๊ฑด์—์„œ ์นจ์ง€ํ•˜์—ฌ ์„œ๋กœ์˜ UPV๋ฅผ ๋น„๊ตํ•˜์˜€๋‹ค. ์ด๋ฅผ ํ†ตํ•ด ์žฌ๋ น์— ์˜ํ•œ ํšจ๊ณผ์™€ ์ž๊ธฐ์น˜์œ ์— ์˜ํ•œ ํšจ๊ณผ๋ฅผ ๊ตฌ๋ณ„ํ•˜๋Š” ์‹œ๋„๋ฅผ ํ•˜์˜€๋‹ค. ์นจ์ง€ 30์ผ๊ณผ 60์ผ์—์„œ ์žฌ๋ นํšจ๊ณผ๋ฅผ ๊ณ ๋ คํ•œ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ์˜ ์ฐจ์ด(/Resources/kci/JKCI.2017.29.1.011/images/PIC1C6C.gif, /Resources/kci/JKCI.2017.29.1.011/images/PIC1CBB.gif)๋Š” ๋‹ค์Œ ์‹์„ ํ†ตํ•ด ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ control (uncracked)๊ณผ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ(cracked) ์‹œํ—˜์ฒด์˜ UPV ์ฐจ์ด๋ฅผ ๊ณ„์‚ฐํ•˜์˜€๋‹ค.

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(1-5)

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(1-6)

๋‹ด์ˆ˜์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด๋“ค์˜ ๋น„๊ต๋Š” ์‹ (1-1)๊ณผ ์‹ (1-4)์— ์˜ํ•ด ๊ณ„์‚ฐ๋œ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด์˜ 30์ผ ์นจ์ง€ ํ›„ UPV ๋ณ€ํ™”์œจ(/Resources/kci/JKCI.2017.29.1.011/images/PIC1D99.gif)์—์„œ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด์˜ 30์ผ ์นจ์ง€ ํ›„ UPV ๋ณ€ํ™”์œจ(/Resources/kci/JKCI.2017.29.1.011/images/PIC1DE8.gif)์˜ ์ฐจ์ด๋ฅผ ์‹ (1-5)๋กœ ๊ณ„์‚ฐํ•˜์˜€๋‹ค. ๋˜ํ•œ ์นจ์ง€ 60์ผ์—์„œ ๊ท ์—ด ์‹œํ—˜์ฒด์™€ control ์‹œํ—˜์ฒด์˜ UPV ์ฐจ์ด๋Š” ์‹ (1-6)์œผ๋กœ ๊ณ„์‚ฐํ•˜์˜€๋‹ค. ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด๋„ ๋™์ผํ•œ ๋ฐฉ๋ฒ•์œผ๋กœ ์‹ (1-5)์™€ (1-6)์— ์˜ํ•ด ๊ณ„์‚ฐํ•˜์˜€๋‹ค. ์‹ (1-5)์™€ ์‹ (1-6)์˜ ๊ณ„์‚ฐ ๊ฐ’์˜ ์ฐจ์ด๊ฐ€ ์–‘์ˆ˜(+)์ธ ๊ฒฝ์šฐ๋Š” ์žฌ๋ น์— ์˜ํ•œ UPV ์ฆ๊ฐ€๋ณด๋‹ค ์ž๊ธฐ์น˜์œ ์— ์˜ํ•œ UPV ์ฆ๊ฐ€๊ฐ€ UPV ํ–ฅ์ƒ์— ๋” ํฐ ์˜ํ–ฅ์„ ๋ฏธ์ณค๋‹ค๋Š” ์˜๋ฏธ์ด๋‹ค. ๋ฐ˜๋Œ€๋กœ ๊ฐ’์˜ ์ฐจ์ด๊ฐ€ ์Œ์ˆ˜(-)์ธ ๊ฒฝ์šฐ๋Š” ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ณด๋‹ค ์žฌ๋ น์— ์˜ํ•œ ํšจ๊ณผ๊ฐ€ UPV ํ–ฅ์ƒ์— ๋” ํฐ ์˜ํ–ฅ์„ ๋ฏธ์นœ๋‹ค๋Š” ์˜๋ฏธ์ด๋‹ค.

Fig. 4์™€ Fig. 5์€ ์‹ (1-5)์™€ (1-6)์— ์˜ํ•ด ๊ณ„์‚ฐ๋œ ์žฌ๋ นํšจ๊ณผ๋ฅผ ๊ณ ๋ คํ•œ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ๋‚˜ํƒ€๋‚ธ ๊ฒƒ์ด๋‹ค. ๋‹ด์ˆ˜์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด๋Š” ์นจ์ง€ 30์ผ์—์„œ์˜ ์ž๊ธฐ์น˜์œ ํšจ๊ณผ์™€ ์žฌ๋ นํšจ๊ณผ์˜ ์ฐจ์ด๋น„๊ต๋Š” Fig. 4(a)์— ๋‚˜ํƒ€๋‚œ ๋ฐ”์™€ ๊ฐ™์ด /Resources/kci/JKCI.2017.29.1.011/images/PIC1E46.gif์˜ ๊ฐ’์ด ์–‘์ˆ˜(+) ๊ฐ’๋“ค๋กœ ์ž๊ธฐ์น˜์œ ์— ์˜ํ•œ UPV ์ฆ๊ฐ€๊ฐ€ ์žฌ๋ นํšจ๊ณผ์— ์˜ํ•œ UPV ์ฆ๊ฐ€๋ณด๋‹ค ํฐ ์˜ํ–ฅ์„ ๋ฏธ์น˜๋Š” ๊ฒƒ์œผ๋กœ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ๊ทธ๋ฆฌ๊ณ  ์นจ์ง€์˜จ๋„๊ฐ€ ๋†’์„์ˆ˜๋ก ๋™์ผํ•œ GGBFS ์น˜ํ™˜์œจ์—์„œ /Resources/kci/JKCI.2017.29.1.011/images/PIC1E86.gif๋„ ๋†’๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ๋˜ํ•œ GGBFS์˜ ์น˜ํ™˜์œจ์ด 10%์—์„œ 30%๋กœ ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ /Resources/kci/JKCI.2017.29.1.011/images/PIC1F23.gif๊ฐ€ ์ฆ๊ฐ€ํ•˜๊ณ  ์žˆ์—ˆ๋‹ค. ์ด๋Š” GGBFS์˜ ์น˜ํ™˜์œจ์ด ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ GGBFS์˜ ๋Šฆ์€ ์ˆ˜ํ™”๋ฐ˜์‘์ด ๊ท ์—ด๋ฉด์˜ ์ž๊ธฐ์น˜์œ ์— ์ผ์ • ๋ถ€๋ถ„ ์˜ํ–ฅ์„ ์ฃผ์–ด UPV๊ฐ€ ์ฆ๊ฐ€ํ•˜์˜€๋‹ค. ์นจ์ง€ 60์ผ์—์„œ์˜ /Resources/kci/JKCI.2017.29.1.011/images/PIC1F63.gif๋Š” Fig. 4(b)์— ๋‚˜ํƒ€๋‚œ ๊ฒƒ์ฒ˜๋Ÿผ ์นจ์ง€ 30์ผ๋ณด๋‹ค(Fig. 4(a)) ๋‚ฎ์€, โ€œ0โ€์— ๊ทผ์ ‘ํ•œ ์ˆ˜์น˜๋ฅผ ๋‚˜ํƒ€๋‚ด๊ณ  ์žˆ์œผ๋ฉฐ ์ผ๋ถ€ ์นจ์ง€์˜จ๋„์™€ GGBFS ์น˜ํ™˜์œจ์—์„œ๋Š” ์Œ์ˆ˜(-)๊ฐ’์„ ๋‚˜ํƒ€๋‚ด์—ˆ๋‹ค. ์ด๋Š” ์นจ์ง€ 30์ผ ์ดํ›„๋ถ€ํ„ฐ ์นจ์ง€ 60์ผ๊นŒ์ง€ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๊ฐ€ ๊ธ‰๊ฒฉํžˆ ๊ฐ์†Œํ•˜๊ณ  ์žˆ์Œ์„ ๋‚˜ํƒ€๋‚ธ๋‹ค.

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Fig. 4 The relative change rate of UPV for specimens immersed in tap water

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Fig. 5 The relative change rate of UPV for specimens immersed in sea water

ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด๋“ค์˜ ๊ฒฝ์šฐ ์นจ์ง€ 30์ผ์—์„œ์˜ /Resources/kci/JKCI.2017.29.1.011/images/PIC1FA2.gif๋Š” ๋‹ด์ˆ˜์—์„œ์™€ ๋งˆ์ฐฌ๊ฐ€์ง€๋กœ ์–‘(+)์˜ ๊ฐ’์„ ๋‚˜ํƒ€๋‚ด๊ณ  ์žˆ์—ˆ๋‹ค. ์นจ์ง€ ์˜จ๋„์— ๋Œ€ํ•œ ์˜ํ–ฅ์€ 5โ„ƒ์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด๋“ค์˜ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ์— ์˜ํ•œ UPV ์ฆ๊ฐ€๊ฐ€ ๊ฐ€์žฅ ์ผฐ๊ณ , ๊ทธ๋‹ค์Œ์ด 25ยฐC์™€ 15ยฐC์ˆœ์„œ์˜€๋‹ค. ์ด๋Š” ์˜จ๋„๊ฐ€ ๋†’์„์ˆ˜๋ก ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ์— ์˜ํ•œ UPV ์ฆ๊ฐ€์œจ์ด ํ–ฅ์ƒ๋˜๋Š” ๋‹ด์ˆ˜์˜ ๊ฒฝํ–ฅ๊ณผ๋Š” ๋‹ค์†Œ ๋‹ค๋ฅธ ํŠน์„ฑ์ธ๋‹ค. ์นจ์ง€ 60์ผ์—์„œ ์ธก์ •ํ•œ /Resources/kci/JKCI.2017.29.1.011/images/PIC1FE2.gif๋Š” 0% GGBFS์˜ 15ยฐC ์นจ์ง€ ์‹œํ—˜์ฒด์™€ 20% GGBFS ์น˜ํ™˜ํ•œ 15ยฐC ์‹œํ—˜์ฒด๋ฅผ ์ œ์™ธํ•˜๊ณ ๋Š” ๋ชจ๋‘ ์Œ์ˆ˜(-)๊ฐ’์„ ๋‚˜ํƒ€๋‚ด๊ณ  ์žˆ์—ˆ๋‹ค. ์ด๋Š” ์นจ์ง€ 30์ผ๋ถ€ํ„ฐ 60์ผ๊นŒ์ง€ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋Š” ๊ฑฐ์˜ ๋ฏธ๋ฏธํ•ด์ง€๊ณ  ์žฌ๋ น์— ์˜ํ•œ ํšจ๊ณผ๊ฐ€ UPV ์ฆ๊ฐ€์˜ ์ฃผ์š” ์š”์ธ์ž„์„ ์˜๋ฏธํ•œ๋‹ค. ๋”ฐ๋ผ์„œ ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด์˜ ๊ฒฝ์šฐ ์ž๊ธฐ์น˜์œ ๋Š” ์นจ์ง€ 30์ผ๊นŒ์ง€ ๊ฐ€์žฅ ํ™œ๋ฐœํžˆ ๋ฐœ์ƒํ•˜๊ณ  ์ดํ›„์—๋Š” ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๊ฐ€ ๊ธ‰๊ฒฉํžˆ ์•ฝํ™”๋˜๋Š” ๊ฒƒ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค. ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์˜ ์ด๋Ÿฌํ•œ ์ฐจ์ด๋Š” ํ•ด์ˆ˜ ์ค‘์— ํ•จ์œ ๋˜์–ด ์žˆ๋Š” ๋‹ค์–‘ํ•œ ๋ฌผ์งˆ๋“ค์— ์˜ํ•ด ์นจ์ง€ 30์ผ๊นŒ์ง€ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๊ฐ€ ์ด‰์ง„๋˜์ง€๋งŒ ์ดํ›„์—๋Š” ๊ทธ ํšจ๊ณผ๊ฐ€ ๊ฐ์†Œ๋˜๋Š” ๊ฒƒ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค. ์นจ์ง€ 30์ผ ์ดํ›„์— ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ์˜ ๊ฐ์†Œ๋Š” ๋‹ค์–‘ํ•œ ์›์ธ์„ ์ƒ๊ฐํ•  ์ˆ˜ ์žˆ๋Š”๋ฐ, ๊ท ์—ด๋ฉด์˜ ๋ฏธ์ˆ˜ํ™” ์ž…์ž๋“ค์˜ ์žฌ์ˆ˜ํ™”, ๋ฐ˜์‘์ƒ์„ฑ๋ฌผ์งˆ ๊ทธ๋ฆฌ๊ณ  ์นจ์ „๋ฌผ ๋“ฑ์ด ๊ท ์—ด๋ฉด์„ ๋ฎ์–ด ํ•ด์ˆ˜ ๋˜๋Š” ๋‹ด์ˆ˜์™€์˜ ์ ‘์ด‰๋ฉด์ ์ด ์ค„์–ด ์ƒˆ๋กœ์šด ๋ฐ˜์‘์ƒ์„ฑ๋ฌผ์งˆ์ด๋‚˜ ์žฌ์ˆ˜ํ™” ๋“ฑ์ด ์ƒ์„ฑ๋˜๋Š” ๊ฒƒ์ด ๋ฐฉํ•ด๋ฐ›๊ธฐ ๋•Œ๋ฌธ์œผ๋กœ ์ƒ๊ฐํ•  ์ˆ˜ ์žˆ๋‹ค.

Palin et al.24)์€ GGBFS-OPC ํ˜ผํ•ฉ ์‹œ๋ฉ˜ํŠธ ๋ชจ๋ฅดํƒ€๋ฅด์˜ ์ž๊ธฐ์น˜์œ  ์‹คํ—˜์—์„œ ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด์˜ ๊ท ์—ด์น˜์œ  ์†๋„๊ฐ€ ๋‹ด์ˆ˜ ์นจ์ง€ ์‹œํ—˜์ฒด๋ณด๋‹ค ๋” ๋น ๋ฅด๋‹ค๊ณ  ํ•˜์˜€๋‹ค. ๊ทธ ์›์ธ์œผ๋กœ ํ•ด์ˆ˜ ์†์— ํฌํ•จ๋œ ๋‹ค์–‘ํ•œ ์ด์˜จ๋“ค์ด ์ž๊ธฐ์น˜์œ ์— ๊ธ์ •์ ์ธ ํšจ๊ณผ๋ฅผ ๋‚˜ํƒ€๋‚ด๊ธฐ ๋•Œ๋ฌธ์ด๋ผ๊ณ  ํ•˜์˜€๋‹ค. ๋ณธ ์—ฐ๊ตฌ์˜ ๋ฒ”์œ„์—์„œ ์‚ดํŽด๋ณผ ๋•Œ ๋‹ด์ˆ˜๋ณด๋‹ค๋Š” ํ•ด์ˆ˜์—์„œ์˜ UPV ์ฆ๊ฐ€์œจ์ด ํ–ฅ์ƒ๋˜๋Š” ๊ฒฐ๊ณผ๋ฅผ ๋ณด์ด๊ณ  ์žˆ์–ด, ์ƒ๋Œ€์ ์œผ๋กœ ํ•ด์ˆ˜์—์„œ์˜ ์ž๊ธฐ์น˜์œ ํšจ๊ณผ๊ฐ€ ๋” ํฐ ๊ฒƒ์œผ๋กœ ๋‚˜ํƒ€๋‚ฌ๋‹ค.

3.2 SEM

Fig. 6๋Š” ์นจ์ง€ 60์ผ์— ๊ท ์—ด์ด ๋ฐœ์ƒ๋œ ์‹œ๋ฃŒ๋“ค์˜ ๊ท ์—ด๋ถ€๋ฅผ SEM ๊ด€์ฐฐํ•œ ๊ฒƒ์ด๋‹ค. ํ•ด์ˆ˜์— ์นจ์ง€ํ–ˆ๋˜ ์‹œํ—˜์ฒด์˜ ๊ท ์—ด๋ถ€์™€ ํ‘œ๋ฉด์—๋Š” ๋ฐ์€ ํฐ์ƒ‰์˜ ์นจ์ „๋ฌผ์ด ์ƒ์„ฑ๋˜์–ด ์žˆ์—ˆ๋‹ค. ํŠน์ด ์ด ์นจ์ „๋ฌผ์€ ๊ท ์—ด์„ ๋”ฐ๋ผ ๋‘๊บผ์šด ๋ ๋ฅผ ํ˜•์„ฑํ•˜๊ณ  ์žˆ์—ˆ๋‹ค(Fig. 6 (a)~(d)). EDS ๋ถ„์„์„ ํ†ตํ•ด ๊ท ์—ด์„ ๋”ฐ๋ผ ์นจ์ „๋œ ๋ฌผ์งˆ(Fig. 6(a)์˜ โ€œaโ€)๊ณผ ๊ท ์—ด ์ฃผ์œ„์˜ ์นจ์ „๋ฌผ(Fig. 6(b)์˜ โ€œbโ€์™€ Fig. 6(e)์˜ โ€œcโ€)์„ ๋ถ„์„ํ•ด ๋ณด์•˜๋‹ค. Fig.7์€ Fig. 6์—์„œ ๋‚˜ํƒ€๋‚œ ์นจ์ „๋ฌผ์งˆ๋“ค์— ๋Œ€ํ•œ EDS ๋ถ„์„ ๊ฒฐ๊ณผ๋ฅผ ๋‚˜ํƒ€๋‚ธ ๊ฒƒ์ด๋‹ค. Fig. 7(a)์™€ (b)๋Š” Fig. 6(a)์˜ โ€œaโ€์ง€์ ๊ณผ Fig. 6(b)์˜ โ€œbโ€ ์ง€์ ์— ๋Œ€ํ•œ EDS ๋ถ„์„ ๊ฒฐ๊ณผ์ด๋‹ค. ์นจ์ „๋ฌผ์€ ํ•ด์ˆ˜ ์ค‘์— ํฌํ•จ๋˜์–ด ์žˆ๋˜ Mg์— ์˜ํ•œ brucite (Mg(OH)2)์˜€๋‹ค. ์‹œํ—˜์ฒด ํ‘œ๋ฉด๊ณผ ๊ท ์—ด์„ ๋”ฐ๋ผ ํ˜•์„ฑ๋œ brucite์— ์˜ํ•ด ๊ท ์—ด์˜ ์ž๊ธฐ์น˜์œ ๊ฐ€ ๋‹ด์ˆ˜์˜ ์ž๊ธฐ์น˜์œ ๋ณด๋‹ค ์ƒ๋Œ€์ ์œผ๋กœ ๋Šฆ๊ฒŒ ๋œ๋‹ค. ์ด๋Š” 30์ผ ์ดํ›„ ๊ธ‰๊ฒฉํ•œ UPV ์ฆ๊ฐ€์œจ์˜ ๊ฐ์†Œ(Fig. 3(b))์™€ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ์˜ ๊ฐ์†Œ(Fig. 5(b))๋ฅผ ๋‚˜ํƒ€๋‚ธ๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ ๋‹ด์ˆ˜์— ์นจ์ง€ํ•œ ๊ท ์—ด ์‹œํ—˜์ฒด์˜ ๊ฒฝ์šฐ ๊ท ์—ด์ด ์„ ๋ช…ํ•˜๊ฒŒ ๊ด€์ฐฐ๋œ๋‹ค(Fig. 6(e)~(h)). ํ•ด์ˆ˜์— ์นจ์ง€๋œ ์‹œํ—˜์ฒด์™€ ๊ฐ™์ด ๊ท ์—ด๋ฉด ์ผ๋ถ€์™€ ํ‘œ๋ฉด์— ๋งŽ์€ ์นจ์ „๋ฌผ์ด ํ™•์ธ๋˜์—ˆ๋‹ค. ์ด ์นจ์ „๋ฌผ์— ๋Œ€ํ•ด Fig. 6(e)์˜ โ€œcโ€ ์ง€์ ์—์„œ ์ƒ์„ฑ๋ฌผ์งˆ์— ๋Œ€ํ•œ EDS ๋ถ„์„์„ ์ˆ˜ํ–‰ํ•˜์˜€๋‹ค. ๊ทธ ๊ฒฐ๊ณผ Fig. 7(c)์— ๋‚˜ํƒ€๋‚œ ๋ฐ”์™€ ๊ฐ™์ด calcium carbonate (CaCO3)์˜€๋‹ค. Fig. 6(h)๋Š” ๋‹ด์ˆ˜์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด์˜ ๊ท ์—ด๋ฉด์„ ํ™•๋Œ€ํ•œ ๊ฒƒ์œผ๋กœ ๊ท ์—ด๋ถ€ ์ฃผ์œ„์— calcium carbonate (CaCO3)๊ฐ€ ์ƒ์„ฑ๋˜์–ด ๊ท ์—ดํญ์ด ์ข์•„์ง„ ๊ฒƒ์„ ํ™•์ธํ•  ์ˆ˜ ์žˆ๋‹ค. ์ด๋Š” ๋‹ด์ˆ˜ ์ค‘์— ์šฉํ•ด๋˜์–ด ์žˆ๋˜ CO2์— ์˜ํ•œ ๊ฒƒ์œผ๋กœ, ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด์˜ ํ‘œ๋ฉด์— ์นจ์ „๋œ ๋ฌผ์งˆ์— ๋Œ€ํ•œ Palin et al.24)์˜ ์—ฐ๊ตฌ๊ฒฐ๊ณผ์—์„œ๋„ ์œ ์‚ฌํ•œ ์นจ์ „๋ฌผ์˜ ๊ฒฐ๊ณผ๋ฅผ ์–ธ๊ธ‰ํ•˜์˜€๋‹ค. ๊ทธ๋Š” ๋‹ด์ˆ˜(fresh-water)์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด์—์„œ๋Š” aragonite๋ฅผ, ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด์—์„œ๋Š” magnesium ์นจ์ „๋ฌผ์„ ๊ด€์ฐฐํ•˜์˜€๋‹ค. ์„ ํ–‰ ์—ฐ๊ตฌ์—์„œ Conjeaud30)์™€ Buenfeld and Newman31) ๋“ฑ์ด ํ•ด์ˆ˜์— ์นจ์ง€๋œ ์‹œํ—˜์ฒด ํ‘œ๋ฉด์— ์ƒ์„ฑ๋œ ๋ฌผ์งˆ์— ๋Œ€ํ•œ ์–ธ๊ธ‰์„ ํ•˜์˜€๋‹ค. ๊ทธ๋“ค์€ ์ด๋Ÿฌํ•œ ํ‘œ๋ฉด ์นจ์ „๋ฌผ์ด ํ•ด์ˆ˜ ์ค‘์˜ magnesium ions์— ์˜ํ•œ ๊ฒƒ์ด๋ผ๊ณ  ํ•˜์˜€๋‹ค.

/Resources/kci/JKCI.2017.29.1.011/images/Figure_CONCRETE_29_01_02_F6.jpg

Fig. 6 SEM image of crack specimens

/Resources/kci/JKCI.2017.29.1.011/images/Figure_CONCRETE_29_01_02_F7.jpg

Fig. 7 EDS Results

๋ณธ ์—ฐ๊ตฌ์—์„œ, ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด์˜ UPV ์ฆ๊ฐ€์œจ ๋“ฑ์ด ์นจ์ง€ ํ•ด์ˆ˜์˜ ์˜จ๋„์— ๋”ฐ๋ฅธ ๊ฒฝํ–ฅ์„ฑ์ด ์—†์—ˆ๋˜ ๊ฒƒ์€ ๊ท ์—ด๋ฉด์„ ๋”ฐ๋ผ ์ƒ์„ฑ๋œ brucite์˜ ์˜ํ–ฅ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค. ํ‘œ๋ฉด์— ๋ฐœ์ƒ๋œ ๊ท ์—ด์˜ ์ผ๋ถ€ ๋˜๋Š” ์ „๋ถ€๋ฅผ brucite๊ฐ€ ์ƒ์„ฑ๋˜์–ด ๋งˆ์น˜ ๊ท ์—ด์ด ์น˜์œ ๋˜์–ด ๊ท ์—ด์ด ๋‹ซํžŒ ๊ฒƒ์ฒ˜๋Ÿผ UPV ๊ฐ’์ด ๋‚˜ํƒ€๋‚œ ๊ฒƒ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค. ์ด๋Š” ํ‘œ๋ฉด์˜ ๊ท ์—ด์„ ๋”ฐ๋ผ brucite๊ฐ€ ์ƒ์„ฑ๋จ์œผ๋กœ ์ธํ•ด ์นจ์ง€ ํ›„ ์ผ์ • ๊ธฐ๊ฐ„ ์ดํ›„์—๋Š” ๊ท ์—ด ๋‚ด๋ถ€์— ์›ํ™œํ•œ ํ•ด์ˆ˜์˜ ํ๋ฆ„๊ณผ ์ž๊ธฐ์น˜์œ  ๋ฌผ์งˆ ๊ฒฐ์ •ํ™”์ž‘์šฉ ๋“ฑ์„ ์ €ํ•ดํ•˜์—ฌ ์ƒ๋Œ€์ ์œผ๋กœ ๋‚ฎ์€ ์ž๊ธฐ์น˜์œ ํšจ๊ณผ๋ฅผ ์œ ๋ฐœํ•˜๋Š” ๊ฒƒ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค. ์ด๋Ÿฌํ•œ brucite์˜ ์ƒ์„ฑ์€ ํ•ด์ˆ˜ ์ค‘์˜ ๋ฌด๊ธฐ์—ผ๋ฅ˜์ธ magnesium์˜ ์˜ํ–ฅ์œผ๋กœ brucite์˜ ์ƒ์„ฑ์œผ๋กœ ์ธํ•ด ์นจ์ง€ํ•ด์ˆ˜์˜ ์˜จ๋„์— ๋”ฐ๋ฅธ UPV ํŠน์„ฑ์„ ๋ช…ํ™•ํžˆ ํŒŒ์•…ํ•  ์ˆ˜ ์—†์—ˆ๋‹ค.

4. ๊ฒฐ    ๋ก 

ํ•ด์ˆ˜(sea-water)์™€ ๋‹ด์ˆ˜(tap-water), 5ยฐC, 15ยฐC ๊ทธ๋ฆฌ๊ณ  25ยฐC์˜ ์นจ์ง€์˜จ๋„, GGBFS ์น˜ํ™˜์œจ 0%, 10%, 20% ๊ทธ๋ฆฌ๊ณ  30%์—์„œ UPV ์ธก์ •์„ ํ†ตํ•œ ์ž๊ธฐ์น˜์œ  ์ธก์ •๊ณผ ์žฌ๋ นํšจ๊ณผ๋ฅผ ๊ณ ๋ คํ•œ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ์— ๋Œ€ํ•œ ์—ฐ๊ตฌ ๊ฒฐ๊ณผ๋ฅผ ์š”์•ฝํ•˜๋ฉด ๋‹ค์Œ๊ณผ ๊ฐ™๋‹ค.

1)ํ•ด์ˆ˜์™€ ๋‹ด์ˆ˜์— ์นจ์ง€ํ•œ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด์™€ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด ๋ชจ๋‘ ์นจ์ง€ ํ›„ 30์ผ๊ณผ 60์ผ์— ์ธก์ •ํ•œ UPV๊ฐ€ ์ฆ๊ฐ€ํ•˜์˜€๋‹ค. ์ด๋Š” ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜ ์ค‘์— ์นจ์ง€๋œ ๊ท ์—ด์ด ๋ฐœ์ƒํ•œ ์‹œํ—˜์ฒด์˜ ์ž๊ธฐ์น˜์œ ํšจ๊ณผ๋ฅผ UPV ์ธก์ •์„ ํ†ตํ•ด ํ™•์ธ ํ•  ์ˆ˜ ์žˆ์—ˆ๋‹ค.

2)GGBFS ์น˜ํ™˜์œจ์ด 0%์—์„œ 30%๋กœ ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ ์นจ์ง€ 30์ผ๊ณผ 60์ผ์—์„œ UPV ์ฆ๊ฐ€์œจ์ด ์ฆ๊ฐ€ํ•˜๊ณ  ์žˆ์—ˆ๋‹ค. ์ด๋Š” GGBFS์˜ ์น˜ํ™˜์€ ์ž๊ธฐ์น˜์œ ํšจ๊ณผ ํ–ฅ์ƒ๊ณผ ์นจ์ง€๊ธฐ๊ฐ„์˜ ์ฆ๊ฐ€์—๋„ ์œ ํšจํ•œ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ๋‚˜ํƒ€๋‚ด๋Š” ๊ฒƒ์œผ๋กœ ์„ ํ–‰์—ฐ๊ตฌ๊ฒฐ๊ณผ๋“ค๊ณผ ์œ ์‚ฌํ•œ ๊ฒฝํ–ฅ์„ ๋‚˜ํƒ€๋‚ด์—ˆ๋‹ค. ๋”ฐ๋ผ์„œ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ๋†’์ด๊ณ  ์นจ์ง€๊ธฐ๊ฐ„์ด ๊ธธ์–ด์ง€๋Š” ํ™˜๊ฒฝ์„ ๊ณ ๋ คํ•  ๋•Œ GGBFS์˜ ์น˜ํ™˜์ด ์ž๊ธฐ์น˜์œ ํšจ๊ณผ ์ฆ๋Œ€์— ํšจ๊ณผ์ ์ธ ๊ฒƒ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค.

3)๋‹ด์ˆ˜์˜ ๊ฒฝ์šฐ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด์˜ ์ž๊ธฐ์น˜์œ ํšจ๊ณผ๋Š” ์นจ์ง€ ์˜จ๋„๊ฐ€ 25ยฐC > 15ยฐC > 5ยฐC ์ˆœ์„œ๋กœ ๋†’์€ ์นจ์ง€ ์˜จ๋„์—์„œ UPV ์ฆ๊ฐ€์œจ๋„ ๋†’์•„ ์ž๊ธฐ์น˜์œ ํšจ๊ณผ๊ฐ€ ํ–ฅ์ƒ๋˜์—ˆ๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ ํ•ด์ˆ˜์˜ ๊ฒฝ์šฐ SEM ๊ด€์ฐฐ์„ ํ†ตํ•ด ์‹œํ—˜์ฒด ํ‘œ๋ฉด์˜ ๊ท ์—ด์„ ๋”ฐ๋ผ ์ƒ์„ฑ๋œ brucite ๋“ฑ์˜ ์˜ํ–ฅ์œผ๋กœ ์นจ์ง€ ์˜จ๋„์— ๋”ฐ๋ฅธ UPV ํŠน์„ฑ์ด ๋ช…ํ™•ํ•˜์ง€ ์•Š์•˜๋‹ค.

4)๊ท ์—ด ๋ฐœ์ƒ ํ›„ ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜ ๋ชจ๋‘ ์นจ์ง€ 30์ผ๊นŒ์ง€์˜ UPV ์ฆ๊ฐ€์œจ์ด ์นจ์ง€ 30์ผ์—์„œ 60์ผ๊นŒ์ง€์˜ UPV ์ฆ๊ฐ€์œจ๋ณด๋‹ค ์ƒ๋Œ€์ ์œผ๋กœ ๋†’๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ์ด๋Š” ๊ท ์—ด ๋ฐœ์ƒ ํ›„ ์นจ์ง€ 30์ผ๊นŒ์ง€์˜ ๊ธฐ๊ฐ„ ๋™์•ˆ ์ž๊ธฐ์น˜์œ ํšจ๊ณผ๊ฐ€ ๊ฐ€์žฅ ํ™œ๋ฐœํ•˜๋‹ค. ๋˜ํ•œ ์นจ์ง€ 30์ผ๊นŒ์ง€๋Š” UPC ์ฆ๊ฐ€๋Š” ์ž๊ธฐ์น˜์œ ํšจ๊ณผ๊ฐ€ ์žฌ๋ น์˜ ์ฆ๊ฐ€์— ์˜ํ•œ ํšจ๊ณผ๋ณด๋‹ค ํฐ ์˜ํ–ฅ์„ ๋ฏธ์น˜๊ณ  30์ผ ์ดํ›„ ์—๋Š” ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ์™€ ์žฌ๋ น์˜ ํšจ๊ณผ ๋ชจ๋‘ ๊ธ‰๊ฒฉํžˆ ๊ฐ์†Œํ•˜๊ฑฐ๋‚˜ ์žฌ๋ น์— ์˜ํ•œ UPV ์ฆ๊ฐ€ ํšจ๊ณผ๊ฐ€ ์ž๊ธฐ์น˜์œ ์— ์˜ํ•œ ํšจ๊ณผ๋ณด๋‹ค ๋ฏธ์†Œํ•˜๊ฒŒ ํฐ ๊ฒƒ์œผ๋กœ ๋‚˜ํƒ€๋‚ฌ๋‹ค.

๋ณธ ์—ฐ๊ตฌ๊ฒฐ๊ณผ๋ฅผ ํ†ตํ•ด UPV ์ธก์ •๋ฐฉ๋ฒ•์œผ๋กœ ์žฌ๋ นํšจ๊ณผ๋ฅผ ๊ณ ๋ คํ•œ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ํ™•์ธํ•  ์ˆ˜ ์žˆ์—ˆ๊ณ , GGBFS์˜ ์น˜ํ™˜์œจ, ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜, ์นจ์ง€์˜จ๋„ ๋“ฑ์— ๋”ฐ๋ฅธ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ์ธก์ •ํ•˜์˜€๋‹ค. ์—ฐ๊ตฌ ๋ฒ”์œ„ ๋‚ด์—์„œ ์žฌ๋ นํšจ๊ณผ์™€ ์ž๊ธฐ์น˜์œ ํšจ๊ณผ๋ฅผ ๋น„๊ตํ•  ๋•Œ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด๋Š” ์นจ์ง€ 30์ผ๊นŒ์ง€์˜ ์ถฉ๋ถ„ํžˆ ์ ์ ˆํ•œ ์กฐ๊ฑด์„ ๋งˆ๋ จํ•œ๋‹ค๋ฉด ์ž๊ธฐ์ง€์œ  ํšจ๊ณผ๋ฅผ ํ–ฅ์ƒ์‹œ์ผœ ๊ท ์—ด์น˜์œ ์— ํšจ๊ณผ๋ฅผ ๋‚˜ํƒ€๋‚ผ ๊ฒƒ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค.

Acknowledgements

์ด ๋…ผ๋ฌธ์€ 2015๋…„๋„ ์ •๋ถ€(๊ต์œก๋ถ€)์™€ 2013๋…„๋„ ์ •๋ถ€(๋ฏธ๋ž˜์ฐฝ์กฐ๊ณผํ•™๋ถ€)์˜ ์žฌ์›์œผ๋กœ ํ•œ๊ตญ์—ฐ๊ตฌ์žฌ๋‹จ์˜ ์ง€์›์„ ๋ฐ›์•„ ์ˆ˜ํ–‰๋œ ์—ฐ๊ตฌ์ž„(No. NRF-2015R1D1A3A01019583, NRF โ€“ 2013R1-A1A1076089).

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