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Journal of the Korea Concrete Institute

J Korea Inst. Struct. Maint. Insp.
  • Indexed by
  • Korea Citation Index (KCI)

  1. ์ •ํšŒ์›,์ถฉ๋‚จ๋Œ€ํ•™๊ต ๋Œ€ํ•™์› ๊ฑด์ถ•๊ณตํ•™๊ณผ ์„์‚ฌ๊ณผ์ •
  2. ์ •ํšŒ์›,์ถฉ๋‚จ๋Œ€ํ•™๊ต ๋Œ€ํ•™์› ๊ฑด์ถ•๊ณตํ•™๊ณผ ๋ฐ•์‚ฌ๊ณผ์ •
  3. ์ •ํšŒ์›,๊ฐ€์ฒœ๋Œ€ํ•™๊ต ๊ฑด์ถ•๊ณตํ•™๊ณผ ๊ต์ˆ˜
  4. ์ •ํšŒ์›,ํ•œ๊ตญ๊ตํ†ต๋Œ€ํ•™๊ต ๊ฑด์ถ•ํ•™๋ถ€ ๊ต์ˆ˜
  5. ์ •ํšŒ์›,์ถฉ๋‚จ๋Œ€ํ•™๊ต ๊ฑด์ถ•๊ณตํ•™๊ณผ ๊ต์ˆ˜, ๊ต์‹ ์ €์ž



๋ฐ”์ด์˜ค์ฐจ, ์‹œ๋ฉ˜ํŠธ ๋ชจ๋ฅดํƒ€๋ฅด, Fe ํ™œ์„ฑํ™”, ๋ฐ˜๋ณต์••์ถ•, ์ „๊ธฐ์ „๋„์„ฑ
Biochar, Cement mortar, Fe-Activation, Repeated compression, Electrical conductivity

1. ์„œ ๋ก 

๋ฐ”์ด์˜ค์ฐจ(Biochar)๋Š” ๋ฐ”์ด์˜ค๋งค์Šค(Biomass)์™€ ์ˆฏ(Charcoal)์˜ ํ•ฉ์„ฑ์–ด๋กœ, ์‚ฐ์†Œ ๊ณต๊ธ‰์„ ์ฐจ๋‹จํ•œ ์ƒํƒœ์—์„œ ๋ฐ”์ด์˜ค๋งค์Šค๋ฅผ ๊ฐ€์—ด ๋ฐ ์—ฐ์†Œ์‹œ์ผœ ๋งŒ๋“ค์–ด ๋‚ธ ํƒ„์†Œ ํ•จ๋Ÿ‰์ด ๋†’์€ ์œ ๊ธฐ๋ฌผ๊ณผ ์ˆฏ์˜ ์ค‘๊ฐ„ ์„ฑ์งˆ์„ ๊ฐ–๋Š” ๊ณ ํ˜•๋ฌผ์ด๋‹ค(Downie et al., 2012). ๊ตญ๋‚ด์—์„œ๋Š” ๋ฐ”์ด์˜ค์ฐจ๋Š” ํ† ์–‘์— ๋งค๋ฆฝํ•˜์—ฌ ๋Œ€๊ธฐ ์ค‘์˜ ํƒ„์†Œ๋ฅผ ํ† ์–‘์— ๊ฒฉ๋ฆฌํ•˜์—ฌ ์˜จ์‹ค๊ฐ€์Šค(CO2)๋ฅผ ๊ฐ์ถ•ํ•˜๋Š” ํšจ๊ณผ๋ฅผ ๊ฑฐ๋‘˜ ์ˆ˜ ์žˆ์„ ๋ฟ๋งŒ ์•„๋‹ˆ๋ผ ํ† ์–‘์˜ ์ƒํƒœ๊ณ„๋ฅผ ๊ฐœ์„ ํ•  ์ˆ˜ ์žˆ์–ด ํ† ์–‘ ๊ฐœ๋Ÿ‰์ œ๋กœ ๋„๋ฆฌ ์‚ฌ์šฉ๋˜๊ณ  ์žˆ๋Š” ์‹ค์ •์ด๋‹ค(Lee et al., 2021).

์ตœ๊ทผ ์ „ ์„ธ๊ณ„์ ์œผ๋กœ ๋ฐœ์ƒํ•˜๋Š” ํญ์—ผ, ํญ์šฐ ๋ฐ ํญ์„ค ๋“ฑ ์ด์ƒ๊ธฐํ›„ ํ˜„์ƒ์€ ์ธ๋ช… ๋ฐ ์žฌ์‚ฐ ํ”ผํ•ด๋ฟ๋งŒ ์•„๋‹ˆ๋ผ ์‹๋Ÿ‰๋ถ€์กฑ ๋ฐ ํ•ด์ˆ˜๋ฉด ์ƒ์Šน ๋“ฑ์„ ํ†ตํ•ด ์ธ๋ฅ˜์™€ ์ž์—ฐ ์ƒํƒœ๊ณ„์˜ ์ƒ์กด์„ ์œ„ํ˜‘ํ•˜๊ณ  ์žˆ์–ด ์ธ๋ฅ˜๊ฐ€ ์‹œ๊ธ‰ํ•˜๊ฒŒ ํ•ด๊ฒฐํ•ด์•ผ ํ•˜๋Š” ๊ณผ์ œ๋กœ ๋Œ€๋‘๋˜๊ณ  ์žˆ๋‹ค. ์ด๋Ÿฌํ•œ ์ด์ƒ๊ธฐํ›„ ํ˜„์ƒ์˜ ์›์ธ์€ ์˜จ์‹ค๊ฐ€์Šค์— ์˜ํ•œ ์ง€๊ตฌ์˜จ๋‚œํ™”๋ฅผ ๋„˜์–ด์„œ ์ง€๊ตฌ ์—ด๋Œ€ํ™”๋ผ๋Š” ํ•™์„ค์ด ๋– ์˜ค๋ฅด๋ฉด์„œ ์œ ์—” ๊ธฐ๋ณธ ํ˜‘์•ฝ, ๊ตํ† ์˜์ •์„œ, ํŒŒ๋ฆฌ๊ธฐํ›„๋ณ€ํ™”ํ˜‘์•ฝ ๋“ฑ ์˜จ์‹ค๊ฐ€์Šค ๊ฐ์ถ•์„ ์œ„ํ•œ ๊ตญ์ œ์ ์ธ ํ˜‘์•ฝ์„ ํ†ตํ•˜์—ฌ ๋งŽ์€ ๊ตญ๊ฐ€๊ฐ€ ํ•จ๊ป˜ ๋…ธ๋ ฅํ•˜๊ณ  ์žˆ๋‹ค. 2021๋…„ ์šฐ๋ฆฌ๋‚˜๋ผ ํƒ„์†Œ์ค‘๋ฆฝ์œ„์›ํšŒ๋Š” ์—ญ์‹œ 2030๋…„ ๊ตญ๊ฐ€ ์˜จ์‹ค๊ฐ€์Šค ๊ฐ์ถ•๋ชฉํ‘œ๋ฅผ 2018๋…„ ์˜จ์‹ค๊ฐ€์Šค ์ด๋ฐฐ์ถœ๋Ÿ‰ ๋Œ€๋น„ 40 %๋กœ ์„ค์ •ํ•˜์˜€๋‹ค(Lee and Ryoo, 2022).

๊ฑด์„ค์‚ฐ์—…์€ ๊ฑด์„ค์ž์žฌ ์ƒ์‚ฐ ํฌํ•จํ•˜๋Š” ์ „์ฒด ์ƒ์‚ฐ๊ณต์ •๊ณผ ๊ฑด๋ฌผ ์šด์˜ ๋ถ€๋ถ„์—์„œ ์ „ ์„ธ๊ณ„ ์˜จ์‹ค๊ฐ€์Šค์˜ 25 % ์ •๋„๋ฅผ ๋ฐฐ์ถœํ•˜๋Š” ๊ฒƒ์œผ๋กœ ๋ณด๊ณ ๋˜๊ณ  ์žˆ๋‹ค(McKinsey, 2021). ํŠนํžˆ, ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ์ฃผ์žฌ๋ฃŒ์ธ ์‹œ๋ฉ˜ํŠธ๋Š” ๊ฑด์„ค๊ตฌ์กฐ๋ฌผ์˜ ๊ตฌ์ถ•์„ ์œ„ํ•œ ํ•„์ˆ˜์ ์ธ ์žฌ๋ฃŒ์ด์ง€๋งŒ, ์‹œ๋ฉ˜ํŠธ์˜ ์ƒ์‚ฐ๊ณผ์ •์—์„œ ์ „ ์„ธ๊ณ„ ์˜จ์‹ค๊ฐ€์Šค ๋ฐฐ์ถœ๋Ÿ‰์˜ ์•ฝ 8 % ์ •๋„๋ฅผ ๋ฐฐ์ถœํ•˜๋Š” ๋†’์€ ์˜จ์‹ค๊ฐ€์Šค ๋ฐฐ์ถœ ์žฌ๋ฃŒ๋กœ ์ธ์‹๋˜๊ณ  ์žˆ๋‹ค(Han and Choi, 2023). ๋”ฐ๋ผ์„œ ์‹œ๋ฉ˜ํŠธ ์ƒ์‚ฐ๊ณผ์ • ๊ฐœ์„ , ์ €ํƒ„์†Œ ์‹œ๋ฉ˜ํŠธ ๊ฐœ๋ฐœ, ์‹œ๋ฉ˜ํŠธ ๋Œ€์ฒด์žฌ ๊ฐœ๋ฐœ ๋“ฑ ๊ฑด์„ค์‚ฐ์—… ๋ถ„์•ผ์˜ ์˜จ์‹ค๊ฐ€์Šค ๊ฐ์ถ•์„ ์œ„ํ•œ ๋‹ค์–‘ํ•œ ์—ฐ๊ตฌ๊ฐ€ ์ง„ํ–‰๋˜๊ณ  ์žˆ๋‹ค.

ํ˜„์žฌ ์‹œ๋ฉ˜ํŠธ ๋Œ€์ฒด์žฌ๋กœ์จ ์ฃผ๋กœ ์‚ฌ์šฉ๋˜๊ณ  ์žˆ๋Š” ํ”Œ๋ผ์ด์• ์‹œ(Fly Ash)๋Š” ํ™”๋ ฅ๋ฐœ์ „์†Œ ์—๋„ˆ์ง€์›์ธ ์„ํƒ„์˜ ์—ฐ์†Œ ๊ณผ์ •์—์„œ ๋ฐœ์ƒํ•˜๋Š” ๋ถ€์‚ฐ๋ฌผ์ด๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ ์šฐ๋ฆฌ๋‚˜๋ผ์˜ ํƒ„์†Œ์ค‘๋ฆฝ 2050 ๊ณ„ํš์— ๋”ฐ๋ผ 2034๋…„๊นŒ์ง€ ๊ตญ๋‚ด ์„ํƒ„ํ™”๋ ฅ๋ฐœ์ „์†Œ 59์ค‘ 30๊ธฐ๊ฐ€ ๋‹จ๊ณ„์ ์œผ๋กœ ํ์‡„๋  ์˜ˆ์ •(Song et al., 2021)์ด๋ฏ€๋กœ ํ”Œ๋ผ์ด์• ์‹œ ์ƒ์‚ฐ๋Ÿ‰์ด ๊ธ‰๊ฒฉํ•˜๊ฒŒ ๊ฐ์†Œํ•  ๊ฒƒ์œผ๋กœ ์˜ˆ์ƒ๋œ๋‹ค. ์ด๋Ÿฌํ•œ ์ด์œ ๋กœ ๋ฐ”์ด์˜ค์ฐจ๋ฅผ ์‹œ๋ฉ˜ํŠธ ๋Œ€์ฒด์žฌ ๋˜๋Š” ์ž”๊ณจ์žฌ๋กœ ํ™œ์šฉํ•˜๊ธฐ ์œ„ํ•œ ๋‹ค์–‘ํ•œ ์—ฐ๊ตฌ ์ง„ํ–‰๋˜์—ˆ๋‹ค.

Gupta et al.(2018)์˜ ์—ฐ๊ตฌ ๊ฒฐ๊ณผ์— ๋”ฐ๋ฅด๋ฉด ์‹œ๋ฉ˜ํŠธ์˜ 5 %๋ฅผ ๋ชฉ์งˆ๊ณ„ ๋ฐ”์ด์˜ค์ฐจ๋กœ ๋Œ€์ฒด ์‹œ ๋ชจ๋ฅดํƒ€๋ฅด ์ค‘๋Ÿ‰์€ ์•ฝ 7 % ๊ฐ์†Œํ•˜๊ณ  ๋ชฉ์žฌ ๋ฐ ์Œ์‹๋ฌผ ํ๊ธฐ๋ฌผ ๋ฐ”์ด์˜ค์ฐจ๋ฅผ ๊ฐ๊ฐ 3 % ํ˜ผ์ž… ์‹œ ๋ชจ๋ฅดํƒ€๋ฅด ํ”Œ๋กœ์šฐ๋Š” 13 % ๋ฐ 10 % ์ €ํ•˜๋˜์—ˆ์œผ๋ฉฐ ์ด๋Š” ๋ฐ”์ด์˜ค์ฐจ์˜ ๊ธฐ๊ณต ๊ตฌ์กฐ ๋ฐ ์ด์— ๋”ฐ๋ฅธ ๋†’์€ ํก์ˆ˜์œจ์— ๊ธฐ์ธํ•œ ๊ฒƒ์œผ๋กœ ๋ณด๊ณ ๋˜์—ˆ๋‹ค. ์‹œ๋ฉ˜ํŠธ ๋Œ€์ฒด์žฌ๋กœ ๋ฐ”์ด์˜ค์ฐจ์˜ ์ ์šฉ์— ๋”ฐ๋ฅธ ์‹œ๊ณต์„ฑ ์ €ํ•˜๋Š” ๊ณ ์„ฑ๋Šฅ ๊ฐ์ˆ˜์ œ๋ฅผ ์‚ฌ์šฉํ•˜์—ฌ ๊ฐœ์„ ํ•  ์ˆ˜ ์žˆ๋‹ค(Sirico et al., 2020). ๋ฐ”์ด์˜ค์ฐจ๋ฅผ ์‹œ๋ฉ˜ํŠธ ์ค‘๋Ÿ‰์˜ 1 % ์ด์ƒ ํ˜ผ์ž… ์‹œ ์‹œ๋ฉ˜ํŠธ ๋ณตํ•ฉ์ฒด์˜ ์••์ถ•๊ฐ•๋„๋Š” ๊ฐ์†Œํ•˜๋Š” ๊ฒฝํ–ฅ์„ ๋ณด์˜€์œผ๋ฉฐ ์ด๋Š” ๋ฐ”์ด์˜ค์ฐจ์˜ ๋†’์€ ํก์ˆ˜์œจ ๋ฐ ๊ธฐ๊ณต ๊ตฌ์กฐ๊ฐ€ ์‹œ๋ฉ˜ํŠธ์— ์˜ํ•œ ์ˆ˜ํ™”๋ฌผ ์ƒ์„ฑ์„ ์ €ํ•ดํ•˜๊ณ  ๊ฒฝํ™”์ฒด ๋‚ด๋ถ€ ๊ณต๊ทน์„ ํ˜•์„ฑํ•˜์—ฌ ๋ฐ€๋„๋ฅผ ๊ฐ์†Œ์‹œ์ผฐ๊ธฐ ๋•Œ๋ฌธ์œผ๋กœ ์•Œ๋ ค์ ธ ์žˆ๋‹ค. ์ชผ๊ฐฌ ๋ฐ ํœจ์ธ์žฅ๊ฐ•๋„์— ์žˆ์–ด์„œ๋„ ์••์ถ•๊ฐ•๋„ ํŠน์„ฑ๊ณผ ์œ ์‚ฌํ•œ ๊ฒฝํ–ฅ์„ ๋ณด์˜€์œผ๋ฉฐ ์‹ค๋ฆฌ์นด ํ„๊ณผ ๊ฐ™์€ ํ˜ผํ™”์žฌ์™€ ๋‹ฌ๋ฆฌ ๋ฐ”์ด์˜ค์ฐจ๋Š” ๋‚ฎ์€ ํฌ์กธ๋ž€ ๋ฐ˜์‘์„ฑ์„ ๊ฐ–๊ณ  ์žˆ๊ธฐ ๋•Œ๋ฌธ์œผ๋กœ ๋ณด๊ณ ๋˜๊ณ  ์žˆ๋‹ค(Akinyemi and Adesina, 2020). ํ˜„์žฌ๊นŒ์ง€ ๋‹ค์–‘ํ•œ ์ข…๋ฅ˜์˜ ๋ฐ”์ด์˜ค์ฐจ๋ฅผ ์‹œ๋ฉ˜ํŠธ ๋Œ€์ฒด์žฌ๋กœ ํ™œ์šฉํ•˜๊ณ ์ž ํ•˜๋Š” ์—ฐ๊ตฌ ๊ฒฐ๊ณผ๋ฅผ ๊ทผ๊ฑฐ๋กœ ๋ณผ ๋•Œ, ํ”Œ๋ผ์ด์• ์‹œ ๋ฐ ๊ณ ๋กœ์Šฌ๋ž˜๊ทธ์™€ ๊ฐ™์€ ๊ธฐ์กด ์‹œ๋ฉ˜ํŠธ ๋Œ€์ฒด ํ˜ผํ™”์žฌ์™€ ๊ฐ™์ด ๋ฐ”์ด์˜ค์ฐจ๋ฅผ ๋‹ค๋Ÿ‰์œผ๋กœ ์‹œ๋ฉ˜ํŠธ๋ฅผ ๋Œ€์ฒดํ•˜๋Š” ๋ฐ๋Š” ์‹œ๊ณต์„ฑ ๋ฐ ๊ฐ•๋„ ํŠน์„ฑ ์ธก๋ฉด์—์„œ ํ•œ๊ณ„๊ฐ€ ์žˆ๋Š” ๊ฒƒ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค.

๊ฑด์„ค์‹œ์žฅ์˜ ๋…ธ๋™๋ ฅ ๊ฐ์†Œ, ์ž์žฌ๋น„ ์ƒ์Šน ๋ฐ ๋‹ค์–‘ํ•œ ๊ทœ์ œ ํ™˜๊ฒฝ ๋ณ€ํ™”์— ๋”ฐ๋ฅธ ๊ฑด์„ค ์ƒ์‚ฐ์„ฑ ์ €ํ•˜๋ฅผ ํ•ด์†Œํ•˜๊ธฐ ์œ„ํ•˜์—ฌ ๊ฑด์ถ•๋ฌผ์˜ ์„ค๊ณ„, ์‹œ๊ณต ๋ฐ ์œ ์ง€๊ด€๋ฆฌ ๋“ฑ์˜ ์ „ ์ƒ์• ์ฃผ๊ธฐ์— ๊ฑธ์ณ ์Šค๋งˆํŠธ ๊ฑด์„ค๊ธฐ์ˆ ์˜ ํ™œ์šฉ์ด ๋ชจ์ƒ‰๋˜๊ณ  ์žˆ๋‹ค. ํŠนํžˆ ๊ฑด์ถ•๋ฌผ์˜ ๋ชจ๋‹ˆํ„ฐ๋ง ๊ธฐ์ˆ ์€ ์‹œ๊ณต ๋ฐ ์œ ์ง€๊ด€๋ฆฌ ๋‹จ๊ณ„์—์„œ ๊ตฌ์กฐ์ฒด์˜ ์ •๋ฐ€ ์‹œ๊ณต ๋ฐ ์‚ฌ์šฉ ์ค‘ ๊ฑด์ „๋„ ์œ ์ง€๋ฅผ ์œ„ํ•œ ํ•ต์‹ฌ๊ธฐ์ˆ ๋กœ ํ‰๊ฐ€๋˜๊ณ  ์žˆ๋‹ค. ๋ชจ๋‹ˆํ„ฐ๋ง ๊ธฐ์ˆ ์˜ ์œ ํšจ์„ฑ์€ ๊ตฌ์กฐ๋ฌผ์˜ ๋ณ€ํ˜• ๋ฐ ์‘๋ ฅ์„ ๊ฐ์ง€ํ•  ์ˆ˜ ์žˆ๋Š” ์„ผ์„œ์— ์˜ํ•ด ๊ฒฐ์ •๋˜๋ฉฐ ์ด๋Ÿฌํ•œ ์„ผ์„œ๋Š” ๊ณ ๋‚ด๊ตฌ์„ฑ, ์ €๋น„์šฉ ๋ฐ ๊ณ„์ธก ์ •๋ณด์˜ ์‹ ๋ขฐ์„ฑ ๋“ฑ์ด ์š”๊ตฌ๋œ๋‹ค. ์ตœ๊ทผ ์ด๋Ÿฌํ•œ ์š”๊ตฌ์กฐ๊ฑด์„ ์ถฉ์กฑํ•˜๋Š” ์„ผ์„œ๋กœ ์‹œ๋ฉ˜ํŠธ ๋ณตํ•ฉ์ฒด์— ์ „๋„์žฌ๋ฃŒ๋ฅผ ํ˜ผ์ž…ํ•œ ๋ณ€ํ˜•๊ณ„์ธก ์„ผ์„œ์— ๋Œ€ํ•œ ์—ฐ๊ตฌ๊ฐ€ ํญ๋„“๊ฒŒ ์ง„ํ–‰๋˜๊ณ  ์žˆ๋‹ค(Dong et al., 2019, Wang et al., 2023). ์‹œ๋ฉ˜ํŠธ ๋ณตํ•ฉ์ฒด ๊ธฐ๋ฐ˜์˜ ๋ณ€ํ˜•๊ฐ์ง€ ์„ผ์„œ ์ œ์ž‘์„ ์œ„ํ•˜์—ฌ ํƒ„์†Œ๋‚˜๋…ธํŠœ๋ธŒ(Carbon Nano Tube, CNT), ๋‹ค์ค‘๋ฒฝํƒ„์†Œ๋‚˜๋…ธํŠœ๋ธŒ(Multi-Walled Carbon Nano Tube, MWCNT), ํƒ„์†Œ๋‚˜๋…ธ์„ฌ์œ (Carbon Nano Fiber, CNF) ๋ฐ ๊ทธ๋ž˜ํ•€(Graphene) ๋“ฑ๊ณผ ๊ฐ™์€ ์ „๋„์žฌ๋ฃŒ์˜ ํ˜ผ์ž…์ด ์š”๊ตฌ๋œ๋‹ค(Pisello et al., 2017). ๊ทธ๋Ÿฌ๋‚˜ ์ด๋Ÿฌํ•œ ์ „๋„์žฌ๋ฃŒ๋Š” ์‹œ๋ฉ˜ํŠธ ๋ณตํ•ฉ์ฒด์— ์ „๋„์„ฑ์„ ๋ถ€์—ฌํ•˜๋Š”๋ฐ ์œ ํšจํ•˜์ง€๋งŒ, ๊ณ ๊ฐ€๋ผ๋Š” ํ•œ๊ณ„์ ์ด ์žˆ๋‹ค.

๋”ฐ๋ผ์„œ, ํ‘์—ฐ(Carbon black), ๊ฐ•์„ฌ์œ  ๋ฐ ๊ณ ๋กœ์Šฌ๋ž˜๊ทธ ๋“ฑ๊ณผ ๊ฐ™์€ ์ƒ๋Œ€์ ์œผ๋กœ ๊ฒฝ์ œ์„ฑ์ด ์žˆ๋Š” ์žฌ๋ฃŒ๋ฅผ ์‹œ๋ฉ˜ํŠธ ๋ณตํ•ฉ์ฒด ๊ธฐ๋ฐ˜ ์„ผ์„œ์˜ ํ™œ์šฉํ•˜๊ณ ์ž ํ•˜๋Š” ์—ฐ๊ตฌ๊ฐ€ ์ง„ํ–‰๋˜์—ˆ๋‹ค(Yun et al., 2023). Rhee et al.(2016)์˜ ์—ฐ๊ตฌ์—์„œ ์™•๊ฒจ ๋ฐ”์ด์˜ค์ฐจ๋กœ๋ถ€ํ„ฐ ์ถ”์ถœ๋œ ๊ทธ๋ž˜ํ•€์„ ํ˜ผ์ž…ํ•œ ์‹œ๋ฉ˜ํŠธ ๋ณตํ•ฉ์ฒด์˜ ์ „๊ธฐ ์ „๋„์„ฑ ๋ฐ ๋ฐ˜๋ณต์••์ถ•ํ•˜์—์„œ ๋ณ€ํ˜•๊ฐ์ง€๋Šฅ๋ ฅ์„ ํ‰๊ฐ€ํ•˜์—ฌ ์„ผ์„œ์˜ ์ „๋„์žฌ๋ฃŒ๋กœ ํ™œ์šฉ๊ฐ€๋Šฅ์„ฑ์„ ํ‰๊ฐ€ํ•˜์˜€๋‹ค.

์ตœ๊ทผ ์‹œ๋ฉ˜ํŠธ ๋ณตํ•ฉ์ฒด์— ๊ณ ์ „๋„์„ฑ์„ ๊ฐ–๋Š” ํƒ„์†Œ์ž…์ž๋ฅผ ํ˜ผ์ž…ํ•œ ์ž๊ธฐ๊ฐ์ง€(Self-Sensing) ์„ผ์„œ์— ๋Œ€ํ•œ ๊ฐœ๋ฐœ ๋ฐ ํ™œ์šฉ์— ๋Œ€ํ•œ ์—ฐ๊ตฌ๊ฐ€ ํญ ๋„“๊ฒŒ ์ง„ํ–‰๋˜๊ณ  ์žˆ์œผ๋‚˜(Dinesh et al., 2024) ํƒ„์†Œ๋‚˜๋…ธํŠœ๋ธŒ ๋ฐ ๊ทธ๋ž˜ํ•€๊ณผ ๊ฐ™์€ ๊ณ ์ „๋„์„ฑ ํƒ„์†Œ์ž…์ž๊ฐ€ ๊ณ ๊ฐ€์ด๋ฏ€๋กœ ์‹ค์šฉํ™”ํ•˜๋Š”๋ฐ ํ•œ๊ณ„์ ์„ ๊ฐ–๊ณ  ์žˆ๋‹ค. ์ด์— ๋”ฐ๋ผ ๋ณธ ์—ฐ๊ตฌ์—์„œ๋Š” ์‹œ๋ฉ˜ํŠธ ๋ณตํ•ฉ์ฒด ๊ธฐ๋ฐ˜ ์„ผ์„œ์˜ ์ „๋„๋ฌผ์งˆ๋กœ ๊ณ ๊ฐ€์˜ ์ƒ์šฉํ™”๋œ ํƒ„์†Œ์ž…์ž๋ฅผ ์ €๋น„์šฉ์ธ ๋ฐ”์ด์˜ค์ฐจ ๊ธฐ๋ฐ˜ ์ „๋„๋ฌผ์งˆ๋กœ ๋Œ€์ฒดํ•˜๊ณ ์ž ํ•œ๋‹ค. ์ „๋„์„ฑ ํ–ฅ์ƒ์„ ์œ„ํ•ด ๋ฐ”์ด์˜ค์ฐจ ๊ณต๊ทน ๋‚ด์— ๊ธˆ์†(Fe) ์‚ฐํ™”๋ฌผ์„ ํก์ฐฉํ•˜์—ฌ ํ‘œ๋ฉด ๊ฐœ์งˆํ•œ ๋ฐ”์ด์˜ค์ฐจ๋ฅผ 3 % ํ˜ผ์ž…ํ•œ ์‹œ๋ฉ˜ํŠธ ๋ณตํ•ฉ์ฒด์˜ ์ „๊ธฐ์  ๋ฐ ๋ณ€ํ˜•๊ฐ์ง€ํŠน์„ฑ์„ ํ‰๊ฐ€ํ•˜์˜€๋‹ค.

2. ์‹ค ํ—˜

2.1 Fe ํ™œ์„ฑํ™”

๋ฐ”์ด์˜ค์ฐจ๋Š” ๋†’์€ ํƒ„์†Œ ํ•จ์œ ๋Ÿ‰์„ ๋‚˜ํƒ€๋‚ด์–ด ์‹œ๋ฉ˜ํŠธ ๋ณตํ•ฉ์ฒด์— ์ „๋„์„ฑ์„ ๋ถ€์—ฌํ•  ๊ฒƒ์œผ๋กœ ํŒ๋‹จํ•˜์˜€๊ณ , ์ด์— ๋”ฐ๋ฅธ ์ „๋„์„ฑ์„ ๋” ์ฆ์ง„ํ•˜๊ธฐ ์œ„ํ•ด ์‹คํ—˜์— ์‚ฌ์šฉ๋œ ๋ถ„์‡„๋œ ๋ฐ”์ด์˜ค์ฐจ๋ฅผ pH ๋†๋„ 2.0 ๋ฏธ๋งŒ์˜ ์—ผํ™”์ œ์ด์ฒ ์ˆ˜์šฉ์•ก(Iron chloride Solution)์— ์นจ์ง€์‹œ์ผฐ๋‹ค. ๋ฐ”์ด์˜ค์ฐจ์˜ ๋†’์€ ํก์ˆ˜์„ฑ์„ ๊ณ ๋ คํ•˜์—ฌ 30๋ถ„๊ฐ„ ์šฉ์•ก์„ ์„ž์œผ๋ฉฐ pH ๋†๋„ 10 ์ดˆ๊ณผ์˜ 5 M ์ˆ˜์‚ฐํ™”๋‚˜ํŠธ๋ฅจ(NaOH)์„ ์ฒจ๊ฐ€ํ•˜๊ณ  8์‹œ๊ฐ„ ๋™์•ˆ ๊ธˆ์†(Fe) ์‚ฐํ™”๋ฌผ์„ ๊ณต๊ทน ๋‚ด์— ํก์ฐฉ์‹œ์ผœ ํ™œ์„ฑํ™”ํ•˜์˜€๋‹ค. ์ˆ˜์‚ฐํ™”๋‚˜ํŠธ๋ฅจ ์ฒจ๊ฐ€์— ๋”ฐ๋ฅธ ๋ฐ”์ด์˜ค์ฐจ๋ฅผ ์ฒจ๊ฐ€ํ•œ ์—ผํ™”์ œ์ด์ฒ ์ˆ˜์šฉ์•ก์˜ ์ƒ‰ ๋ณ€ํ™”์—์„œ ๊ฐ•์‚ฐ์„ฑ์˜ ์—ผํ™”์ œ์ด์ฒ ์ˆ˜์šฉ์•ก์˜ ์—ฐ๊ฐˆ์ƒ‰ ์ƒ‰๊น”์ด ๊ฐ•์—ผ๊ธฐ์„ฑ์˜ ์ˆ˜์‚ฐํ™”๋‚˜ํŠธ๋ฅจ์œผ๋กœ ์ธํ•ด ๊ฒ€์€์ƒ‰์œผ๋กœ ๋ฐ”๋€Œ๋Š” ๊ฒƒ์„ ํ™•์ธํ•  ์ˆ˜ ์žˆ์—ˆ๋‹ค(Fig. 1). ๊ธˆ์† ์‚ฐํ™”๋ฌผ์„ ํก์ฐฉ์‹œํ‚จ ํ›„ ์—ฌ๊ณผ์ง€๋ฅผ ์ด์šฉํ•˜์—ฌ Fe๊ฐ€ ํ•จ์œ ๋œ ๋ฐ”์ด์˜ค์ฐจ๋ฅผ ๋ถ„๋ฆฌํ•˜๊ณ  ์ฆ๋ฅ˜์ˆ˜(Deionized water)๋ฅผ ์‚ฌ์šฉํ•˜์—ฌ ๋ฐ”์ด์˜ค์ฐจ๋ฅผ ์„ธ์ฒ™ํ•˜๊ณ  ๊ฑด์กฐํ•˜์˜€๋‹ค. ๊ฑด์กฐ ํ›„ ๊ณต๊ทน ๋‚ด์— ํก์ฐฉ์‹œํ‚จ Fe๋กœ ์ธํ•ด ์ž์„ฑ์„ ์ง€๋‹ˆ๋Š” ๋ฐ”์ด์˜ค์ฐจ๋ฅผ ํ™•์ธํ•˜๋ฉฐ ๋†’์€ ์ „๊ธฐ์ „๋„์„ฑ์„ ๋ฐœํœ˜ํ•  ๊ฒƒ์œผ๋กœ ํŒ๋‹จํ•˜์˜€๋‹ค.

Fig. 1 Sedimentation due to addition of NaOH
../../Resources/ksm/jksmi.2024.28.2.27/fig1.png

2.2 ์‹คํ—˜๊ณ„ํš

๋ณธ ์—ฐ๊ตฌ์—์„œ๋Š” ๊ธˆ์†(Fe) ์‚ฐํ™”๋ฌผ๋กœ ํ™œ์„ฑํ™”๋œ ๋ชฉ์งˆ๊ณ„ ๋ฐ”์ด์˜ค์ฐจ๋ฅผ ํ˜ผ์ž…ํ•œ ๋ชจ๋ฅดํƒ€๋ฅด๋ฅผ ๋ณ€ํ˜•๊ณ„์ธก ์„ผ์„œ๋กœ ํ™œ์šฉํ•˜๊ณ  ์ „๋„ ์„ฑ๋Šฅ์„ ํ‰๊ฐ€ํ•˜๊ณ ์ž ํ•˜์˜€๋‹ค. ์ด์— ๋”ฐ๋ฅธ ์‹คํ—˜๊ณ„ํš์€ Table 1์— ๋‚˜ํƒ€๋‚ธ ๋ฐ”์™€ ๊ฐ™๋‹ค.

์‹œ๋ฉ˜ํŠธ ๋ชจ๋ฅดํƒ€๋ฅด ์ œ์ž‘์„ ์œ„ํ•œ ์„ ํ–‰ ์—ฐ๊ตฌ(Gupta et al., 2021)์— ๋”ฐ๋ฅธ ๋ฐ”์ด์˜ค์ฐจ์˜ ํ•จ์œ ๋Ÿ‰์€ ์‹œ๋ฉ˜ํŠธ ์งˆ๋Ÿ‰๋น„ 3 %๋กœ ์„ค์ •ํ•˜์˜€๋‹ค. ์‹œํ—˜์ฒด์˜ ์–‘์ƒ ์กฐ๊ฑด์€ 25ยฑ 3 โ„ƒ์˜ ์˜จ๋„์—์„œ 28์ผ๊ฐ„ ์ˆ˜์ค‘์–‘์ƒ, 20์ผ๊ฐ„์˜ ๊ธฐ๊ฑด์–‘์ƒ์„ ์ง„ํ–‰ํ•˜์˜€๋‹ค. ์‹คํ—˜ ํ•ญ๋ชฉ์€ ์žฌ๋ น 58์ผ ์ฐจ์˜ ์••์ถ•๊ฐ•๋„์™€ LCR meter๋ฅผ ํ™œ์šฉํ•œ ์ž„ํ”ผ๋˜์Šค ๋ถ„์„์„ ํ†ตํ•ด ํ•จ์ˆ˜์œจ ๋ณ€ํ™”์— ๋”ฐ๋ฅด๋Š” ์ „๊ธฐ์ €ํ•ญ ํŠน์„ฑ ๋ณ€ํ™”์™€ ๋ฐ˜๋ณต์••์ถ•์— ์˜ํ•œ ๋ณ€ํ˜•๊ณ„์ธก ์„ผ์„œ์˜ ๋ณ€ํ˜•๋ฅ ์„ ์ธก์ •ํ•˜๊ณ ์ž ํ•˜์˜€๋‹ค. ์ „๊ธฐํ™”ํ•™์  ์„ฑ๋Šฅ์„ ํ‰๊ฐ€ํ•˜๊ธฐ ์œ„ํ•œ ๋ณ€ํ˜•๊ณ„์ธก ์„ผ์„œ์™€ ์••์ถ•๊ฐ•๋„ ๊ณต์‹œ์ฒด ์ œ์ž‘์„ ์œ„ํ•œ ์‹คํ—˜๋ฐฐํ•ฉ์€ Table 2์— ๋‚˜ํƒ€๋‚ธ ๋ฐ”์™€ ๊ฐ™๋‹ค.

Table 1 Experimental plan

Factors

Type

Binders

OPC, BC(Biochar)

Curing conditions

Temperature 25ยฑ3โ„ƒ

Underwater curing

BC/B

3%

W/B

30%

Test Items

Compressive Strength

LCR meter

Data Logger TDS

Cyclic Loading-Unloading

(58 day)

Using Electrolyte

Iron Chloride Solution, 5M NaOH

Frequency

0.5MHz

AC Volt

1V

Table 2 Mix proportion of cement matrix

Mixture

W/B

(%)

Unit weight(g/ใŽฅ)

Water

Cement

Biochar

Sand

Plain

0.3

300

1000

-

400

BC_3%

0.3

300

970

30

400

2.3 ์‚ฌ์šฉ์žฌ๋ฃŒ

2.3.1 ๋ฐ”์ด์˜ค์ฐจ

๋ฐ”์ด์˜ค์ฐจ๋Š” ๋ฐ”์ด์˜ค๋งค์Šค๋ฅผ ์—ด๋ถ„ํ•ดํ•˜์—ฌ ํ˜•์„ฑ๋˜๋Š” ๋ฐ”์ด์˜ค ์ˆฏ์œผ๋กœ ๋Œ€ํ‘œ์ ์ธ ๋ฐ”์ด์˜ค๋งค์Šค๋กœ ์™•๊ฒจ(Rice husk), ๋ชฉ์žฌ(Wood), ๊ฐ€์ถ• ๋ฐฐ์„ค๋ฌผ(Livestock waste) ๋“ฑ์ด ์žˆ๋‹ค. ๋ณธ ์‹คํ—˜์— ์‚ฌ์šฉ๋œ ๋ฐ”์ด์˜ค์ฐจ๋Š” ๋ฐ”์ด์˜ค๋งค์Šค ์ค‘ ๋†’์€ ํƒ„์†Œ ํ•จ์œ ๋Ÿ‰์„ ๊ฐ€์ง€๊ณ  ์„ ํ–‰ ์—ฐ๊ตฌ(Han and Choi, 2023)์— ์‚ฌ์šฉ๋œ ๋ชฉ์งˆ๊ณ„ ๋ฐ”์ด์˜ค๋งค์Šค๋กœ 450 โ„ƒ ๋ถ€๊ทผ์—์„œ ์—ด๋ถ„ํ•ด๋œ ๊ฒƒ์„ ์‚ฌ์šฉํ•˜์˜€๋‹ค. ๋ชฉ์งˆ๊ณ„ ๋ฐ”์ด์˜ค๋งค์Šค๋ฅผ ์ด์šฉํ•œ ์„ผ์„œ ์ œ์ž‘์„ ์œ„ํ•ด Roll-mill์„ ์‚ฌ์šฉํ•˜์—ฌ 250-350 RPM์œผ๋กœ 30๋ถ„ ์ด์ƒ ๋ถ„์‡„ํ•˜์—ฌ ์‹œ๋ฉ˜ํŠธ ์ž…๋„์™€ ๋น„์Šทํ•˜๊ฒŒ ์ œ์ž‘ํ•˜์˜€๋‹ค. Fig. 2(a)๊ณผ (b)๋Š” ๋ถ„์‡„ ์ „, ํ›„์˜ ๋ชจ์Šต์„ ๋‚˜ํƒ€๋‚ธ ๊ฒƒ์ด๋‹ค.

Fig. 2 Biochar before and after grinding
../../Resources/ksm/jksmi.2024.28.2.27/fig2.png

์žฌ๋ฃŒ ์ž…๋„๋ถ„ํฌ ๋ถ„์„๊ธฐ์ธ PSD(Particle Size Distribution)๋ฅผ ํ™œ์šฉํ•˜์—ฌ ๋ถ„์‡„๋œ ๋ชฉ์งˆ๊ณ„ ๋ฐ”์ด์˜ค์ฐจ์˜ ์ž…๋„ ๋ถ„์„ ๊ฒฐ๊ณผ(Fig. 3), D10์˜ ๊ฒฝ์šฐ 6.47 ฮผm, D50์˜ ๊ฒฝ์šฐ 28.75 ฮผm, D90์˜ ๊ฒฝ์šฐ 123.83 ฮผm๋กœ ํ‰๊ท  47.43 ฮผm์ด๋‹ค. ์‹œ๋ฉ˜ํŠธ ์ž…๋„๋ถ„ํฌ ํ‰๊ท  50 ฮผm๋ฅผ ๊ฐ์•ˆํ–ˆ์„ ๋•Œ ๋น„์Šทํ•œ ์ž…๋„๋ฅผ ๊ฐ€์ง€๊ณ  ์žˆ์–ด ๋ฏธ์„ธ ์ž…์ž๋ฅผ ํ†ตํ•ด ์‹œ๋ฉ˜ํŠธ ๋ณตํ•ฉ์ฒด ๋‚ด๋ถ€ ๊ณต๊ทน์„ ๋ฐ€์‹คํ•˜๊ฒŒ ์ฑ„์›€์œผ๋กœ์จ ๊ฐ•๋„๋ฅผ ์ฆ์ง„ํ•˜๊ณ  ์ „๊ธฐ์ „๋„์„ฑ์„ ์ค„ ๊ฒƒ์œผ๋กœ ํŒ๋‹จํ•˜์˜€๋‹ค.

Fig. 4(a)๋Š” ร—1500, (b)๋Š” ร—10000์˜ ๋ฐฐ์œจ๋กœ ์ดฌ์˜ํ•œ ๋ถ„์‡„๋œ ๋ฐ”์ด์˜ค์ฐจ์˜ SEM(Scanning Electron Microscope)์„ ๋‚˜ํƒ€๋‚ธ ๊ฒƒ์ด๋‹ค. ๋ถ„์‡„๋ฅผ ์ง„ํ–‰ํ•œ ํ›„์—๋„ ๋ฐ”์ด์˜ค์ฐจ ๋‚ด๋ถ€์˜ ๋‹ค๊ณต์„ฑ ๊ตฌ์กฐ๋ฅผ ํ™•์ธํ•  ์ˆ˜ ์žˆ์—ˆ์œผ๋ฉฐ, ๋Œ€๋ถ€๋ถ„ 125 ฮผm ์ดํ•˜๋กœ ๋ถ„์‡„๋œ ๊ฒƒ์„ ํ™•์ธํ•  ์ˆ˜ ์žˆ์—ˆ๋‹ค. ๋ถ„์‡„๋œ ๋ฐ”์ด์˜ค์ฐจ์˜ ๋ฏธ์„ธ ๊ธฐ๊ณต์„ ํ†ตํ•ด ์—ผํ™”์ œ์ด์ฒ ์ˆ˜์šฉ์•ก์ด ์ถฉ๋ถ„ํžˆ ํก์ˆ˜๋จ์— ๋”ฐ๋ผ ๋ฐ”์ด์˜ค์ฐจ๊ฐ€ ์ „๊ธฐ์ „๋„์„ฑ์„ ๊ฐ€์งˆ ๊ฒƒ์œผ๋กœ ํŒ๋‹จํ•˜์˜€๋‹ค.

Fig. 3 Particle size distribution of biochar
../../Resources/ksm/jksmi.2024.28.2.27/fig3.png
Fig. 4 SEM result of after grinding biochar
../../Resources/ksm/jksmi.2024.28.2.27/fig4.png

2.3.2 ์‹œ๋ฉ˜ํŠธ ๋ฐ ๊ณจ์žฌ

๋ณธ ์‹คํ—˜์— ์‚ฌ์šฉ๋œ ์‹œ๋ฉ˜ํŠธ๋Š” ๊ตญ๋‚ด โ€˜Hโ€™ ์‚ฌ์˜ ๋ฐ€๋„ 3.14 g/ใŽค, ๋ถ„๋ง๋„ 3,750 ใŽ /g์ธ ๋ณดํ†ต ํฌํ‹€๋žœ๋“œ ์‹œ๋ฉ˜ํŠธ๋ฅผ ์‚ฌ์šฉํ•˜์˜€๋‹ค.

๋ณธ ์‹คํ—˜์— ์‚ฌ์šฉ๋œ ์ž”๊ณจ์žฌ๋กœ ๋น„์ค‘ 2.61 g/ใŽค์ธ 5 mm์˜ ๊ทœ์‚ฌ๋ฅผ ์‚ฌ์šฉํ•˜์˜€๋‹ค.

2.4 ์‹คํ—˜๋ฐฉ๋ฒ•

์••์ถ•๊ฐ•๋„ ์‹œํ—˜์ฒด๋Š” ์ˆ˜๊ฒฝ์„ฑ ์‹œ๋ฉ˜ํŠธ ๋ชจ๋ฅดํƒ€๋ฅด์˜ ์••์ถ• ๊ฐ•๋„ ์‹œํ—˜๋ฐฉ๋ฒ•(KS L 5109)์„ ๊ธฐ์ค€์œผ๋กœ 50ร—50ร—50 mm3 ํฌ๊ธฐ๋กœ ์ œ์ž‘ํ•˜์˜€๋‹ค(Fig. 5(a)). ์••์ถ•๋ ฅ ๋„์ž… ์‹œ ๋ฐœ์ƒํ•˜๋Š” ์ˆ˜์ง ๋ฐ ์ˆ˜ํ‰ ๋ณ€ํ˜•๋ฅ ์„ ์ธก์ •ํ•˜๊ธฐ ์œ„ํ•ด ์‹œํ—˜์ฒด์˜ ๊ฐ ๋ฐฉํ–ฅ์œผ๋กœ 2๊ฐœ์”ฉ ์ด 4๊ฐœ์˜ ์ฝ˜ํฌ๋ฆฌํŠธ ๊ฒŒ์ด์ง€๋ฅผ ๋ถ€์ฐฉํ•˜๊ณ , ์„ผ์„œ ๋Šฅ๋ ฅ์„ ๋ฐœํœ˜ํ•˜๋Š” ํ•จ์ˆ˜์œจ์—์„œ ์••์ถ•๊ฐ•๋„๋ฅผ ์ธก์ •ํ•˜๊ธฐ ์œ„ํ•ด 7.5 %์˜ ํ•จ์ˆ˜์œจ์„ ๊ณ ์ •ํ•˜์—ฌ ์••์ถ•๊ฐ•๋„๋ฅผ ์ธก์ •ํ•˜์˜€๋‹ค(Fig. 5(c)).

Fig. 5 Compressive strength and sensor testing specimens
../../Resources/ksm/jksmi.2024.28.2.27/fig5.png

์—ผํ™”์ œ์ด์ฒ ์ˆ˜์šฉ์•ก์— ์นจ์ง€์‹œํ‚จ ๋ชฉ์งˆ๊ณ„ ๋ฐ”์ด์˜ค์ฐจ๋ฅผ ํ˜ผ์ž…ํ•œ ๋ชจ๋ฅดํƒ€๋ฅด์˜ ์ „๊ธฐ์ „๋„์„ฑ์„ ์ธก์ •ํ•˜๊ธฐ ์œ„ํ•ด 40ร—40ร—80 mm3 ํฌ๊ธฐ์˜ ๋ณ€ํ˜•๊ณ„์ธก ์„ผ์„œ๋ฅผ ์ œ์ž‘ํ•˜๊ณ (Fig. 5(b)), ์ „๊ธฐ์ €ํ•ญ ์ธก์ •์„ ํ†ตํ•œ ์ „๊ธฐ์ „๋„์„ฑ์„ ํŒ๋‹จํ•˜๊ธฐ ์œ„ํ•ด 10, 15 mm ๊ฐ„๊ฒฉ์œผ๋กœ ํ™ˆ์„ ํŒŒ๋‚ธ ํ›„ ๊ตฌ๋ฆฌ์„ ์„ ๊ฐ๊ณ  ์‹œํ—˜์ฒด์™€ ๊ตฌ๋ฆฌ์„  ์‚ฌ์ด์˜ ๊ณต๊ทน์„ ์ฑ„์šฐ๊ธฐ ์œ„ํ•ด ์‹ค๋ฒ„ํŽ˜์ด์ŠคํŠธ๋ฅผ ์ ์šฉํ•˜์˜€๋‹ค. ๋ณธ ์‹คํ—˜์—์„  ์ „ํ•ด์งˆ์„ ์‚ฌ์šฉํ•˜์ง€ ์•Š๊ณ  ๊ธˆ์†(Fe) ์‚ฐํ™”๋ฌผ์— ํ™œ์„ฑํ™”ํ•œ ๋ฐ”์ด์˜ค์ฐจ ์†Œ์žฌ์˜ ํ•จ์ˆ˜์œจ ๋ณ€ํ™”์— ๋”ฐ๋ฅธ ์ „๊ธฐ์ €ํ•ญ ํŠน์„ฑ ํ™•์ธ์„ ์œ„ํ•ด 10, 9.7, 9.0, 8.1, 7.5, 5.9, 4.5 %์˜ ํ•จ์ˆ˜์œจ์„ ์„ค์ •ํ•˜์˜€๋‹ค.

LCR meter๋ฅผ ํ™œ์šฉํ•˜์—ฌ ํ•จ์ˆ˜์œจ์— ๋”ฐ๋ฅธ ์ „๊ธฐ์ €ํ•ญ ์ธก์ •์„ ์ง„ํ–‰ํ•˜๊ณ  ์ž„ํ”ผ๋˜์Šค(Impedance)๋ฅผ ํ™œ์šฉํ•˜์—ฌ ๋ถ„์„ํ•˜์˜€๋‹ค. ์ž„ํ”ผ๋˜์Šค๋Š” ์ €ํ•ญ(Resistor), ์ธ๋•ํ„ฐ(Inductor), ์ปคํŒจ์‹œํ„ฐ(Capacitor)์˜ ํ•ฉ์œผ๋กœ ์ด๋ฃจ์–ด์ ธ ์žˆ๋Š”๋ฐ, Eq. (1)์— ๋‚˜ํƒ€๋‚ธ ๋ฐ”์™€ ๊ฐ™๋‹ค. R์€ ์ €ํ•ญ์˜ ํฌ๊ธฐ๋ฅผ ์˜๋ฏธํ•˜๋ฉฐ, ๋ ˆ์ง€์Šคํ„ด์Šค(R)๋ผ ๋ถ€๋ฅธ๋‹ค. L๊ณผ C๋ฅผ ํ•ฉํ•˜์—ฌ ๋ฆฌ์•กํ„ด์Šค(X)๋ผ๊ณ  ํ•˜๋ฉฐ, ๋ฆฌ์•กํ„ด์Šค๋Š” ์ธ๋•ํ„ฐ์˜ ํฌ๊ธฐ์ธ ์ธ๋•ํ„ฑ์Šค(Inductance)์— ์˜ํ•œ ์œ ๋„์„ฑ ๋ฆฌ์•กํ„ด์Šค(Inductive Reactance)์™€ ์ปคํŒจ์‹œํ„ฐ์˜ ํฌ๊ธฐ์ธ ์ปคํŒจ์‹œํ„ด์Šค(Capacitance)์— ์˜ํ•œ ์šฉ๋Ÿ‰์„ฑ ๋ฆฌ์•กํ„ด์Šค(Capative Reactance)๋กœ ๊ตฌ์„ฑ๋˜์–ด ์žˆ๋‹ค. ๋ณธ ์‹คํ—˜์€ ์œ„์ƒ์„ ๊ณ ๋ คํ•˜์ง€ ์•Š์•„๋„ ๋˜๋Š” DC ํšŒ๋กœ๋ฅผ ์‚ฌ์šฉํ•˜์˜€๊ณ , ์ฃผํŒŒ์ˆ˜ ์˜์—ญ์€ 0.5 MHz๋กœ ๋†’์ง€ ์•Š๊ธฐ์— ์œ ๋„์„ฑ ๋ฆฌ์•กํ„ด์Šค์˜ ํฌ๊ธฐ๋ฅผ ์ƒ๋žตํ•  ์ˆ˜ ์žˆ์–ด Eq. (2)๋ฅผ ํ™œ์šฉํ•˜์—ฌ ์ž„ํ”ผ๋˜์Šค ๋ณ€ํ™”๋Ÿ‰์„ ๊ตฌํ•˜์—ฌ ํ‰๊ฐ€ํ•˜์˜€๋‹ค.

(1)
Z=R+L+C(ฮฉ)
(2)
Z=\sqrt{R^{2}+X_{C}^{2}}(ฮฉ)

Fig. 5(d)๋Š” ๋งŒ๋Šฅ์žฌ๋ฃŒ์‹œํ—˜๊ธฐ(UTM)๋ฅผ ์‚ฌ์šฉํ•˜์—ฌ ์ธก์ •ํ•œ ์••์ถ•๊ฐ•๋„์˜ 10, 30, 50, 70, 90 %์˜ ํ•˜์ค‘์œผ๋กœ ๋ฐ˜๋ณต ์••์ถ•์‹œํ—˜์„ ์‹ค์‹œํ•˜๋Š” ๊ฒƒ์„ ๋‚˜ํƒ€๋‚ธ ๊ฒƒ์ด๋‹ค. ๋ณ€ํ˜•๊ณ„์ธก ์„ผ์„œ์˜ ์•ˆ์ •๋œ ์ „๊ธฐ์ €ํ•ญ ์ธก์ •์„ ์œ„ํ•ด FPP(Four-Point Probe) ๋ฐฉ์‹์œผ๋กœ ์‹คํ—˜์„ ์ง„ํ–‰ํ•˜์˜€๊ณ , ๋ฐ˜๋ณต ์••์ถ•์žฌํ•˜์™€ ๋™์‹œ์— TDS๋ฅผ ์‚ฌ์šฉํ•˜์—ฌ Strain gauge์˜ ๋ณ€ํ˜•๋ฅ ๊ณผ LCR meter๋ฅผ ์‚ฌ์šฉํ•˜์—ฌ ์ „๊ธฐ์ €ํ•ญ์„ ์ธก์ •ํ•˜๊ณ  ๋ณ€ํ˜•๊ฐ์ง€๋Šฅ๋ ฅ์„ ํ‰๊ฐ€ํ•˜์˜€๋‹ค. ์••์ถ•์‘๋ ฅ ๋„์ž…์— ๋”ฐ๋ฅธ ๋ฐ”์ด์˜ค์ฐจ๋ฅผ ํ˜ผ์ž…ํ•œ ๋ชจ๋ฅดํƒ€๋ฅด์˜ ๋ณ€ํ˜•๊ฐ์ง€๋Šฅ๋ ฅ์„ ๋ถ„์„ํ•˜๊ธฐ ์œ„ํ•ด ์••์ถ•์‘๋ ฅ ๋ฒ”์œ„์—์„œ Eq. (3)์˜ ๋ฌผ์ฒด๊ฐ€ ๊ฐ€์ง„ ํŠน์„ฑ์— ๋”ฐ๋ผ์„œ ์ „๊ธฐ์˜ ํ๋ฆ„์„ ๋ฐฉํ•ดํ•˜๋Š” ์ •๋„์ธ ๊ณ ์œ  ์ €ํ•ญ(ฯ)์„ ๊ตฌํ•˜์˜€๋‹ค. ์—ฌ๊ธฐ์„œ A๋Š” ๋ฌผ์ฒด ๋‹จ๋ฉด์ (16 cm2), L์€ ์ „๊ทน ๊ฐ„ ๊ฑฐ๋ฆฌ(15 cm)์ด๋‹ค. Eq. (4)์— ๋‚˜ํƒ€๋‚ธ ๋ฐ”์™€ ๊ฐ™์ด ๊ณ ์œ  ์ €ํ•ญ์˜ ๋ณ€ํ™”๋Ÿ‰(โ–ณฯ)์„ ์ดˆ๊ธฐ ๊ณ ์œ  ์ €ํ•ญ(ฯ0)์œผ๋กœ ๋‚˜๋ˆˆ ๊ณ ์œ  ์ €ํ•ญ์˜ ๋ณ€ํ™”๋น„(Fractional Change in Resistivity, FCR)์„ ์‚ฌ์šฉํ•˜๊ณ , ๋ณ€ํ˜•๊ฐ์ง€๋Šฅ๋ ฅ์˜ ๋ฏผ๊ฐ๋„๋Š” Eq. (5)์˜ FCR์„ ์••์ถ•์‘๋ ฅ(ฯƒc)์ด ๊ฐ€ํ•ด์กŒ์„ ๋•Œ ์••์ถ• ๋ณ€ํ˜•๋ฅ (ฮตc)์„ ๋‚˜๋ˆˆ ๊ฒŒ์ด์ง€ ์ƒ์ˆ˜(Gauge Factor, GF)๋ฅผ ํ™œ์šฉํ•˜์˜€๋‹ค.

(3)
\rho =R\times\dfrac{A}{L}(ฮฉ c m)
(4)
FCR=\dfrac{\rho -\rho_{0}}{\rho_{0}}\times 100=\dfrac{\triangle\rho}{\rho_{0}}\times 100(\%)
(5)
GF=\dfrac{FCR}{\varepsilon}

3. ์‹คํ—˜๊ฒฐ๊ณผ ๋ฐ ๋ถ„์„

3.1 ์••์ถ•๊ฐ•๋„

๋ณธ ์‹คํ—˜์—์„œ์˜ ์••์ถ•๊ฐ•๋„ ์‹œํ—˜์ฒด์˜ ์ธก์ •์€ ์‹œ๋ฉ˜ํŠธ์˜ ๊ฐ•๋„ ์‹œํ—˜ ๋ฐฉ๋ฒ•(KS L ISO 679)์— ๋”ฐ๋ผ ์žฌ๋ น 58์ผ ์ฐจ์˜ ์‹œ๋ฉ˜ํŠธ ๋ชจ๋ฅดํƒ€๋ฅด์™€ ๋ชฉ์งˆ๊ณ„ ๋ฐ”์ด์˜ค์ฐจ๋ฅผ ํ˜ผ์ž…ํ•œ ๋ชจ๋ฅดํƒ€๋ฅด์˜ ์••์ถ•๊ฐ•๋„๋ฅผ ์ธก์ •ํ•˜์˜€๋‹ค(Fig. 6). ์••์ถ•๊ฐ•๋„ ์ธก์ •์„ ์ง„ํ–‰ํ•˜๊ณ , ๋ฐ”์ด์˜ค์ฐจ๋ฅผ ํ˜ผ์ž…ํ•œ ๋ชจ๋ฅดํƒ€๋ฅด์˜ ์••์ถ•์‘๋ ฅ-์ˆ˜์ง ๋ฐ ์ˆ˜ํ‰ ๋ณ€ํ˜•๋ฅ  ๊ณก์„ ์„ Fig. 7๊ณผ ๊ฐ™์ด ๋‚˜ํƒ€๋‚ด์—ˆ๋‹ค.

Plain์˜ ๊ฒฝ์šฐ 48.52 MPa, BC_3 %์˜ ๊ฒฝ์šฐ 59.52 MPa๋กœ ๋ชฉ์งˆ๊ณ„ ๋ฐ”์ด์˜ค์ฐจ๋ฅผ ํ˜ผ์ž…ํ•œ ๋ชจ๋ฅดํƒ€๋ฅด์˜ ๊ฐ•๋„๊ฐ€ ๋” ๋†’์€ ๊ฒƒ์„ ํ™•์ธํ•˜์˜€๋‹ค. ์ด๋Š” ๋ฐ”์ด์˜ค์ฐจ์˜ ํ‘œ๋ฉด์ ์ด ๋„“์€ ๋ฏธ์„ธ๊ตฌ์กฐ์™€ ๋‹ค๊ณต์„ฑ ๊ตฌ์กฐ๋กœ ์ธํ•œ ์ดˆ๊ธฐ ์ˆ˜๋ถ„ ๋ณด์œ ๊ฐ€ ์ดˆ๊ธฐ ๊ฒฝํ™” ๋‹จ๊ณ„ ๋™์•ˆ ์‹œ๋ฉ˜ํŠธ ๋งคํŠธ๋ฆญ์Šค ๋‚ด์˜ ์ž์œ ์ˆ˜๋ฅผ ๊ฐ์†Œ์‹œ์ผœ ์น˜๋ฐ€ํ™”๋ฅผ ์œ ๋„ํ•˜๊ณ , ์ถ”ํ›„ ๋‚ด๋ถ€์ ์œผ๋กœ ๊ณต๊ธ‰๋˜์–ด ๊ฐ•๋„์— ์˜ํ–ฅ์„ ๋ผ์น˜๋Š” ๊ฒƒ์œผ๋กœ ํŒ๋‹จํ•˜์˜€๋‹ค. ์••์ถ•์‘๋ ฅ ๋„์ž… ์‹œ ๋ฐ”์ด์˜ค์ฐจ๋ฅผ ํ˜ผ์ž…ํ•œ ๋ชจ๋ฅดํƒ€๋ฅด์˜ ๊ฐ€๋ ฅ๋ฐฉํ–ฅ ๋ฐ ํšก๋ฐฉํ–ฅ ๋ณ€ํ˜•๋ฅ ์ด ์‹œ๋ฉ˜ํŠธ ๋ชจ๋ฅดํƒ€๋ฅด์— ๋น„ํ•ด ๋†’๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋Š”๋ฐ, ๋ชฉ์งˆ๊ณ„ ๋ฐ”์ด์˜ค์ฐจ ์†Œ์žฌ์˜ ์žฌ๋ฃŒ์  ํŠน์„ฑ์— ์˜ํ•ด ๋‚˜ํƒ€๋‚œ ๊ฒƒ์œผ๋กœ ํŒ๋‹จํ•˜์˜€๋‹ค.

Fig. 6 Compressive strength of cement mortar
../../Resources/ksm/jksmi.2024.28.2.27/fig6.png
Fig. 7 Stress-strain curve of cement mortar
../../Resources/ksm/jksmi.2024.28.2.27/fig7.png
Fig. 8 SEM result of mortar containing biochar
../../Resources/ksm/jksmi.2024.28.2.27/fig8.png

๋˜ํ•œ ๋ถ„์‡„๋œ ๋ฐ”์ด์˜ค์ฐจ์˜ ์ž…๋„๊ฐ€ ๊ณ„๋ฉด ์˜์—ญ(10~50 ฮผm)๊ณผ ๋น„์Šทํ•œ ์ž…๋„๋ฅผ ๊ฐ€์ง€๊ณ  ์žˆ์–ด ์ถฉ์ง„์žฌ ์—ญํ• ์„ ํ•˜๋ฉฐ, ์‹œ๋ฉ˜ํŠธ ํŽ˜์ด์ŠคํŠธ์™€ ๊ณจ์žฌ ์‚ฌ์ด์˜ ๊ณ„๋ฉด ์˜์—ญ์˜ ๊ณต๊ทน์„ ์ฑ„์›Œ ๋†’์€ ์••์ถ•๊ฐ•๋„๋ฅผ ๋‚˜ํƒ€๋‚ธ ๊ฒƒ์œผ๋กœ ํŒ๋‹จํ•˜์˜€๋‹ค(Fig. 8).

3.2 ์ž„ํ”ผ๋˜์Šค ์ธก์ •๊ฒฐ๊ณผ

LCR meter๋ฅผ ํ™œ์šฉํ•œ ์‹œ๊ฐ„์— ๋”ฐ๋ฅธ ํ•จ์ˆ˜์œจ ๋ณ€ํ™”์˜ ์ž„ํ”ผ๋˜์Šค ๋ณ€ํ™”๋Ÿ‰์„ Fig. 9์— ๋‚˜ํƒ€๋‚ด์—ˆ๋‹ค. Fig. 10์€ ํ•จ์ˆ˜์œจ์— ๋”ฐ๋ฅธ ์ž„ํ”ผ๋˜์Šค ๋ณ€ํ™”๋Ÿ‰์˜ ํ‰๊ท ๊ณผ ์ดˆ๊ธฐ ์ €ํ•ญ์„ ์„ ํ˜•์œผ๋กœ ๋‚˜ํƒ€๋‚ธ ๊ฒƒ์ด๋‹ค. ํ•จ์ˆ˜์œจ์ด ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ ์ž„ํ”ผ๋˜์Šค ๋ณ€ํ™”๋Ÿ‰์€ ์ฆ๊ฐ€ํ•˜๋Š” ๊ฒƒ์„ ํ™•์ธํ•  ์ˆ˜ ์žˆ์—ˆ๊ณ , ์ดˆ๊ธฐ ์ €ํ•ญ์˜ ๊ฒฝ์šฐ ๊ฐ์†Œํ•˜๋Š” ๊ฒƒ์„ ํ™•์ธํ•˜์˜€๋‹ค. ์ด๋Š” Ran et al.(2023)์˜ ์—ฐ๊ตฌ์—์„œ๋„ ์œ ์‚ฌํ•œ ํŠน์„ฑ์„ ๋ณด์ธ๋‹ค. ํ•จ์ˆ˜๋Ÿ‰์ด ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ ์ „๊ธฐ์ „๋„์„ฑ์€ ์ฆ๊ฐ€ํ•˜์ง€๋งŒ, ๋ณ€ํ˜•๊ฐ์ง€์— ์žˆ์–ด ๋ฏผ๊ฐ๋„๊ฐ€ ์ฆ๊ฐ€ํ•˜๊ธฐ ๋•Œ๋ฌธ์— ์ž„ํ”ผ๋˜์Šค ๋ณ€ํ™”๋Ÿ‰์ด ์ฆ๊ฐ€ํ•˜๋Š” ๊ฒƒ์œผ๋กœ ํŒ๋‹จํ•˜์˜€๋‹ค.

Fig. 9 โ–ณZ over time by moisture content
../../Resources/ksm/jksmi.2024.28.2.27/fig9.png
Fig. 10 โ–ณZ, R0 according to moisture content
../../Resources/ksm/jksmi.2024.28.2.27/fig10.png

Fig. 10์˜ ํ•จ์ˆ˜์œจ 7.5 % ๊ตฌ๊ฐ„์—์„œ ์•ˆ์ •๋œ ์ „๊ธฐ์ €ํ•ญ์„ ํ™•์ธํ•˜์˜€๋Š”๋ฐ, ๊ธˆ์†(Fe) ์‚ฐํ™”๋ฌผ์— ํ™œ์„ฑํ™”ํ•œ ๋ฐ”์ด์˜ค์ฐจ ์„ผ์„œ์˜ ์ˆ˜๋ถ„ ํ•จ๋Ÿ‰์ด 7.5 % ๊ตฌ๊ฐ„์ผ ๋•Œ ๊ณต๊ทน ๋‚ด์— ํก์ฐฉ์‹œํ‚จ Fe๋กœ ์ธํ•ด ์†Œ์žฌ ์ž์ฒด์˜ ์•ˆ์ •๋œ ์ „๋„์„ฑ์„ ๊ฐ–๋Š” ๊ฒƒ์œผ๋กœ ํŒ๋‹จํ•˜์˜€๋‹ค.

3.3 ๋ฐ˜๋ณต์••์ถ• ์ธก์ •๊ฒฐ๊ณผ

๋งŒ๋Šฅ์žฌ๋ฃŒ์‹œํ—˜๊ธฐ(UTM)๋ฅผ ์ด์šฉํ•œ ๋ณ€ํ˜•๊ณ„์ธก ์„ผ์„œ๋ฅผ ๋ฐ˜๋ณต์••์ถ•ํ•˜์˜€์„ ๋•Œ ์‹œํ—˜์ฒด๋ณ„ ์‹œ๊ฐ„์— ๋”ฐ๋ฅธ ๋ณ€ํ˜•๋ฅ , ๋ณ€ํ˜•๊ฐ์ง€ํŠน์„ฑ์„ ๋‚˜ํƒ€๋‚ด์—ˆ๋‹ค(Fig. 11).

๋ฐ˜๋ณต์••์ถ•์€ ๋ชจ๋ฅดํƒ€๋ฅด ํ‘œ์ค€ ๊ณต์‹œ์ฒด 3๊ฐœ์˜ ํ‰๊ท  ์••์ถ•๊ฐ•๋„๋ฅผ ๊ธฐ์ค€์œผ๋กœ 10, 30, 50, 70, 90 %์˜ ์••์ถ•์‘๋ ฅ์„ 11ํšŒ์”ฉ ๋ฐ˜๋ณต์žฌํ•˜๋ฅผ ์ง„ํ–‰ํ•˜์˜€๋‹ค. Fig. 11์— ๋‚˜ํƒ€๋‚ธ ๋ฐ”์™€ ๊ฐ™์ด 1๋ฒˆ ์‹œํ—˜์ฒด์˜ ๊ฒฝ์šฐ ์••์ถ•๊ฐ•๋„ 30 % ์ˆ˜์ค€์˜ ๋ฐ˜๋ณต์••์ถ• ๋„์ž… ์‹œ ํŒŒ๊ดด๋˜์—ˆ๊ณ , 3๋ฒˆ ์‹œํ—˜์ฒด์˜ ๊ฒฝ์šฐ ์••์ถ•๊ฐ•๋„ 70 % ์ˆ˜์ค€์˜ ๋ฐ˜๋ณต์••์ถ• ๋„์ž… ์‹œ ํŒŒ๊ดด๋˜์—ˆ๊ณ , 2๋ฒˆ ์‹œํ—˜์ฒด๋Š” ์••์ถ•๊ฐ•๋„ 90 %์˜ ๋ฐ˜๋ณต์••์ถ• ๋„์ž… ์‹œ ํŒŒ๊ดด๋˜์—ˆ๋‹ค. ์ด์— ๋”ฐ๋ผ 90 % ๊นŒ์ง€์˜ ๋ฐ˜๋ณต ์••์ถ•์‘๋ ฅ ๋„์ž… ์‹œ ์••์ถ•๋ณ€ํ˜• ๋ฐ ์ €ํ•ญ์˜ ๋ถ„์ˆ˜๋ณ€ํ™”(Fractional Change Resistivity)๋ฅผ ํ™•์ธํ•˜๊ธฐ ์œ„ํ•ด 2๋ฒˆ ์‹œํ—˜์ฒด๋ฅผ ์„ ์ •ํ•˜์—ฌ ๋ถ„์„ํ•˜์˜€๋‹ค.

Fig. 11 Strain, FCR change over time of sensors
../../Resources/ksm/jksmi.2024.28.2.27/fig11.png
Fig. 12 Self sensing properties of sensor(#2) with biochar
../../Resources/ksm/jksmi.2024.28.2.27/fig12.png

๋ชจ๋“  ์‹œํ—˜์ฒด์—์„œ ๋ฐ˜๋ณต ์••์ถ•์‘๋ ฅ์ด ๋„์ž…๋จ์— ๋”ฐ๋ผ ํ‰๊ท  ์••์ถ• ๋ณ€ํ˜•๋ฅ ์—์„œ ์ž”๋ฅ˜ ๋ณ€ํ˜•์ด ์œ ๋ฐœ๋˜์—ˆ๊ณ , FCR์€ ์••์ถ•์‘๋ ฅ์˜ ์ฆ๊ฐ€์— ๋”ฐ๋ผ ๋‚ฎ์•„์ง€๊ณ , ๊ฐ์†Œ์— ๋”ฐ๋ผ ์ „๋ฐ˜์ ์œผ๋กœ ๋†’์•„์ง€๋Š” ํŠน์„ฑ์„ ๋ณด์˜€๋‹ค. 3๊ฐœ ์‹œํ—˜์ฒด์—์„œ FCR ๋ณ€ํ™”๋Š” ๋Œ€์ฒด์ ์œผ๋กœ ํฐ ์ฐจ์ด๋ฅผ ๋ณด์ด์ง€ ์•Š์•˜๋Š”๋ฐ, ์ด๋Š” ๋ฐ”์ด์˜ค์ฐจ ํ˜ผ์ž…์— ๋”ฐ๋ฅธ ์‹œ๋ฉ˜ํŠธ ๋ณตํ•ฉ์ฒด์—์„œ ์ผ์ • ์ˆ˜์ค€์˜ ์•ˆ์ •๋œ ์ „๊ธฐ์ „๋„์„ฑ์„ ํ™•๋ณดํ•  ์ˆ˜ ์žˆ์—ˆ๊ธฐ ๋•Œ๋ฌธ์œผ๋กœ ํŒ๋‹จํ•˜์˜€๋‹ค.

๋ฐ”์ด์˜ค์ฐจ๋ฅผ ํ˜ผ์ž…ํ•œ ๋ณ€ํ˜•๊ณ„์ธก ์„ผ์„œ(Sensor #2)์— ๋Œ€ํ•˜์—ฌ ์••์ถ•๊ฐ•๋„์˜ 10, 30, 50, 70 %์˜ ๋ฐ˜๋ณต ์••์ถ•์‘๋ ฅ ํ•˜์—์„œ ์••์ถ• ๋ณ€ํ˜•๋ฅ ๊ณผ FCR์„ ๋น„๊ตํ•˜์—ฌ ๋‚˜ํƒ€๋‚ธ ๊ฒฐ๊ณผ(Fig. 12), ์••์ถ• ๋ณ€ํ˜•๋ฅ ์ด ์ฆ๊ฐ€ํ•˜๋ฉฐ FCR์ด ๊ฐ์†Œํ•˜๋Š” ํŠน์„ฑ์„ ๋ณด์˜€๋‹ค. ์ด๋ฅผ ํ†ตํ•ด ์••์ถ• ๋ณ€ํ˜•๊ฐ์ง€ ์„ผ์„œ๋กœ์˜ ํ™œ์šฉ ๊ฐ€๋Šฅ์„ฑ์ด ์žˆ๋Š” ๊ฒƒ์œผ๋กœ ํŒ๋‹จํ•˜์˜€๋‹ค.

๊ทธ๋Ÿฌ๋‚˜ ์••์ถ•์‘๋ ฅ์ด ์ฆ๊ฐ€ํ•˜๋ฉฐ ๊ฒŒ์ด์ง€ ์ƒ์ˆ˜(GF) ๋˜ํ•œ ๊ฐ์†Œํ•˜๊ฑฐ๋‚˜ ์ฆ๊ฐ€ํ•˜๋Š” ๊ฒฝํ–ฅ์„ ๋ณด์ด๊ธฐ ๋•Œ๋ฌธ์— ๋ณ€ํ˜•๊ฐ์ง€๋Šฅ๋ ฅ์—์„  ๋–จ์–ด์ง€๋Š” ๊ฒฝํ–ฅ์„ ๋ณด์˜€๋‹ค. ๋ฐ”์ด์˜ค์ฐจ๋ฅผ ํ˜ผ์ž…ํ•œ ๋ณ€ํ˜•๊ณ„์ธก์—์„œ ๋ฐ˜๋ณต ์••์ถ•์‘๋ ฅ์ด ์ฆ๊ฐ€ํ•˜๊ณ , ์‚ฌ์ดํด์ด ์ง„ํ–‰๋จ์— ๋”ฐ๋ผ ์„ผ์„œ ๋‚ด๋ถ€์˜ ๋ฏธ์„ธ ๊ท ์—ด ๋“ฑ์ด ๋ฐœ์ƒํ•˜์—ฌ ์ „๋„์„ฑ์„ ์ด๋ฃจ๋Š” ๋ฌผ์งˆ์˜ ๋„คํŠธ์›Œํฌ๊ฐ€ ํŒŒ๊ดด ๋˜๋Š” ์†์ƒ๋˜์–ด ๋ณ€ํ˜•๊ฐ์ง€๋Šฅ๋ ฅ์ด ์ผ์ •ํ•˜์ง€ ์•Š๊ฑฐ๋‚˜ ๋ชฉ์งˆ๊ณ„ ๋ฐ”์ด์˜ค์ฐจ ์†Œ์žฌ์˜ ๋‹ค๋ฅธ ๋ฌผ์งˆ๋“ค๋กœ ์ธํ•ด ๋‚˜ํƒ€๋‚œ ๊ฒฐ๊ณผ๋กœ ํŒ๋‹จํ•˜์˜€๋‹ค. ์ด์™€ ์œ ์‚ฌํ•œ ํŠน์„ฑ์„ ์ง€๋‹ˆ๋Š” ํƒ„์†Œ๋‚˜๋…ธํŠœ๋ธŒ ์„ฌ์œ  ๋ณตํ•ฉ์ฒด(Gao et al., 2009)์—์„œ๋„ ๋ณด๊ณ ๋˜๊ณ  ์žˆ๋‹ค.

4. ๊ฒฐ ๋ก 

๋ณธ ์—ฐ๊ตฌ์—์„œ๋Š” ๋†’์€ ๋น„์šฉ์„ ์ง€๋‹Œ ๊ณ ์ „๋„์„ฑ ํƒ„์†Œ์ž…์ž๋ฅผ ๋‚ฎ์€ ๋น„์šฉ์„ ์ง€๋‹Œ ๋ฐ”์ด์˜ค์ฐจ ๊ธฐ๋ฐ˜ ์ „๋„๋ฌผ์งˆ๋กœ ๋Œ€์ฒดํ•˜๊ณ ์ž ํ•˜์˜€๋‹ค. ๋ชฉ์งˆ๊ณ„ ๋ฐ”์ด์˜ค์ฐจ ์‹œ๋ฉ˜ํŠธ ๋ณตํ•ฉ์ฒด ๋ณ€ํ˜•๊ฐ์ง€ ์„ผ์„œ๋ฅผ ์ œ์ž‘ํ•˜๊ณ ์ž ์—ผํ™”์ œ์ด์ฒ ์ˆ˜์šฉ์•ก์— ๋ฐ”์ด์˜ค์ฐจ๋ฅผ ์นจ์ง€์‹œ์ผœ ๊ธˆ์†(Fe) ์‚ฐํ™”๋ฌผ์„ ํ™œ์„ฑํ™”ํ•˜์—ฌ ์ „๊ธฐ์ „๋„์„ฑ์„ ๋ถ€์—ฌํ•˜์˜€๋‹ค. ํ•จ์ˆ˜์œจ์— ๋”ฐ๋ฅธ ์ „๋„์„ฑ์„ ํ‰๊ฐ€ํ•˜๊ธฐ ์œ„ํ•ด ์ „๊ธฐ์ €ํ•ญ์„ ์ธก์ •ํ•˜์˜€๊ณ , ๋ฐ˜๋ณต ์••์ถ•์‹œํ—˜์„ ํ†ตํ•ด ์••์ถ•์‘๋ ฅ์— ๋Œ€ํ•œ ๋ฐ˜๋ณต์žฌํ•˜์— ๋”ฐ๋ฅธ ๋ณ€ํ˜•๊ฐ์ง€๋Šฅ๋ ฅ์„ ํ‰๊ฐ€ํ•˜์˜€๋‹ค. ๋ณธ ์—ฐ๊ตฌ ๋ฒ”์œ„ ๋‚ด์—์„œ ๋‹ค์Œ์˜ ๊ฒฐ๋ก ์„ ์–ป์—ˆ๋‹ค.

1. ๊ธˆ์†(Fe) ์‚ฐํ™”๋ฌผ๋กœ ํ™œ์„ฑํ™”๋œ ๋ชฉ์งˆ๊ณ„ ๋ฐ”์ด์˜ค์ฐจ 3 %๋ฅผ ํ˜ผ์ž…ํ•œ ๋ชจ๋ฅดํƒ€๋ฅด์˜ ๊ฐ•๋„๊ฐ€ OPC์˜ ๊ฐ•๋„๋ณด๋‹ค ๋†’์€ ๊ฒƒ์„ ํ™•์ธํ•  ์ˆ˜ ์žˆ์—ˆ๋‹ค. ์ด๋Š” ๋ถ„์‡„๋œ ๋ฐ”์ด์˜ค์ฐจ์˜ ๋‹ค๊ณต์„ฑ ๊ตฌ์กฐ๋กœ ์ธํ•œ ์ดˆ๊ธฐ ์ˆ˜๋ถ„ ๋ณด์œ ์™€ ๋ฏธ์„ธํ•œ ์ž…์ž๊ฐ€ ๊ณ„๋ฉด ์˜์—ญ์˜ ๊ณต๊ทน์„ ์ฑ„์›Œ ๋‚˜ํƒ€๋‚œ ๊ฒฐ๊ณผ์— ๊ธฐ์ธํ•œ ๊ฒƒ์œผ๋กœ ๋‚˜ํƒ€๋‚ฌ๋‹ค.

2. ํ•จ์ˆ˜์œจ์˜ ์ฆ๊ฐ€์— ๋”ฐ๋ผ ์ดˆ๊ธฐ ์ €ํ•ญ์€ ๊ฐ์†Œํ•˜๊ณ  ์žˆ์œผ๋‚˜ ์‹œ๊ฐ„์— ๋”ฐ๋ฅธ ์ž„ํ”ผ๋˜์Šค ๋ณ€ํ™”๋Ÿ‰์€ ์ฆ๊ฐ€ํ•˜์˜€๋‹ค. ์ด๋Š” ํ•จ์ˆ˜๋Ÿ‰์˜ ์ฆ๊ฐ€๋กœ ์ „๋„์„ฑ์ด ์ฆ๊ฐ€ํ•˜๊ณ  ๋ณ€ํ˜•๊ฐ์ง€๋Šฅ๋ ฅ์˜ ๋ฏผ๊ฐ๋„๋„ ์ฆ๊ฐ€ํ•˜๋Š” ๊ฒƒ์œผ๋กœ ํ™•์ธ๋˜์—ˆ๋‹ค. ๋ฐ”์ด์˜ค์ฐจ ์„ผ์„œ์˜ ํ•จ์ˆ˜๋Ÿ‰์ด 7.5 % ๊ตฌ๊ฐ„์ผ ๋•Œ ์•ˆ์ •๋œ ์ „๊ธฐ์  ํŠน์„ฑ์„ ๋ณด์œ ํ•˜๋Š” ๊ฒƒ์œผ๋กœ ํ™•์ธ๋˜์—ˆ๋‹ค.

3. ๊ธˆ์†(Fe) ์‚ฐํ™”๋ฌผ๋กœ ํ™œ์„ฑํ™”ํ•œ ๋ชฉ์งˆ๊ณ„ ๋ฐ”์ด์˜ค์ฐจ 3 %๋ฅผ ์ „๋„์žฌ๋ฃŒ๋กœ ํ˜ผ์ž…ํ•œ ์‹œ๋ฉ˜ํŠธ ๋ณตํ•ฉ์ฒด ์„ผ์„œ์˜ ์ „๊ธฐ์ €ํ•ญ ํŠน์„ฑ์— ๊ทผ๊ฑฐํ•œ ๋ณ€ํ˜•๊ฐ์ง€๋Šฅ๋ ฅ์€ ๊ธฐ์กด ์ƒ์—…ํ™”๋œ ์ „๋„์žฌ๋ฃŒ์— ๋น„ํ•˜์—ฌ ๋‚ฎ๊ฒŒ ๋‚˜ํƒ€๋‚ฌ์œผ๋‚˜ ์ „๋„์žฌ๋ฃŒ๋กœ์˜ ํ™œ์šฉ ๊ฐ€๋Šฅ์„ฑ์€ ํ™•์ธ๋˜์—ˆ๋‹ค. ๋˜ํ•œ, ๋ฐ”์ด์˜ค์ฐจ์˜ ํ˜ผ์ž…๋ฅ  ์กฐ์ • ๋ฐ ์ƒ์—…์šฉ ์ „๋„์žฌ๋ฃŒ์™€์˜ ํ˜ผ์šฉ, ์ „ํ•ด์งˆ ์‚ฌ์šฉ ๋“ฑ์„ ํ†ตํ•˜์—ฌ ๋ณ€ํ˜•๊ฐ์ง€๋Šฅ๋ ฅ ๊ฐœ์„ ์ด ๊ฐ€๋Šฅํ•  ๊ฒƒ์œผ๋กœ ํŒ๋‹จ๋˜๋ฉฐ ํ–ฅํ›„ ์ด์— ๋Œ€ํ•œ ์ง€์†์ ์ธ ์—ฐ๊ตฌ๊ฐ€ ์š”๊ตฌ๋œ๋‹ค.

๊ฐ์‚ฌ์˜ ๊ธ€

๋ณธ ์ด ์—ฐ๊ตฌ๋Š” 2021๋…„๋„ ์ •๋ถ€(๊ณผํ•™๊ธฐ์ˆ ์ •๋ณดํ†ต์‹ ๋ถ€)์˜ ์žฌ์›์œผ๋กœ ํ•œ๊ตญ์—ฐ๊ตฌ์žฌ๋‹จ ๊ธฐ์ดˆ์—ฐ๊ตฌ์‹ค์‚ฌ์—…์˜ ์ง€์›์„ ๋ฐ›์•„ ์ˆ˜ํ–‰๋˜์—ˆ์Šต๋‹ˆ๋‹ค(No.2021R1A4A2001964).

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