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ํฌ๊ธฐํšจ๊ณผ, ์••์ถ•๊ฐ•๋„, ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰, ์˜ˆ์ธก๋ชจ๋ธ
size effect, compressive strength, dried unit weight, prediction model

  • 1. ์„œ ๋ก 

  • 2. ๊ธฐ์กด ์••์ถ•๊ฐ•๋„์— ๋Œ€ํ•œ ํฌ๊ธฐํšจ๊ณผ ๋ชจ๋ธ

  •   2.1 Baลพant์˜ ํฌ๊ธฐํšจ๊ณผ ๋ชจ๋ธ

  •   2.2 Kim and Eo์˜ ํฌ๊ธฐํšจ๊ณผ ๋ชจ๋ธ

  • 3. ๋ชจ๋ธ์˜ ๊ฐœ๋ฐœ

  •   3.1 ๊ธฐ๋ณธ๊ฐ€์ •

  •   3.2 ๋ชจ๋ธ์˜ ์ œ์•ˆ

  • 4. ๋ชจ๋ธ์˜ ๊ฒ€์ฆ

  •   4.1 ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค ๊ตฌ์ถ•

  •   4.2 ๊ธฐ์กด ์—ฐ๊ตฌ๊ฒฐ๊ณผ์™€์˜ ๋น„๊ต

  • 5. ๊ฒฐ ๋ก 

1. ์„œ    ๋ก 

์ฝ˜ํฌ๋ฆฌํŠธ์˜ ํฌ๊ธฐํšจ๊ณผ๋Š” Gonnerman1)์˜ ์‹คํ—˜์— ์˜ํ•ด ์ตœ์ดˆ๋กœ ์ฆ๋ช…๋˜์—ˆ์œผ๋ฉฐ, ์ดํ›„ ๋‹ค์–‘ํ•œ ๊ฒฝ์šฐ์— ๋Œ€ํ•œ ์‹คํ—˜์„ ํ†ตํ•ด ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ํฌ๊ธฐํšจ๊ณผ๊ฐ€ ์ฝ˜ํฌ๋ฆฌํŠธ ๊ณต์‹œ์ฒด์˜ ๋‹จ๋ฉดํ˜•ํƒœ, ํฌ๊ธฐ, ํ˜•์ƒ๋น„ ๋ฐ ๊ตต์€๊ณจ์žฌ์˜ ์ตœ๋Œ€์น˜์ˆ˜ ๋“ฑ์— ์˜ํ–ฅ ๋ฐ›์Œ์ด ํ™•์ธ๋˜์—ˆ๋‹ค.2-4) Weibull์€ Griffith์˜ ๊ฐ€์ •์„ ๋„์ž…ํ•˜์—ฌ ์„ ํ˜•ํƒ„์„ฑ ํŒŒ๊ดด์—ญํ•™์— ๊ทผ๊ฑฐํ•œ ํ†ต๊ณ„์  ์ ‘๊ทผ ๋ฐฉ๋ฒ•์— ์˜ํ•ด ์ตœ์ดˆ๋กœ ํฌ๊ธฐํšจ๊ณผ๋ฒ•์น™(size effect law)์„ ์ œ์‹œํ•˜์˜€๋‹ค.5) ๊ทธ๋Ÿฌ๋‚˜ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ํŒŒ๊ดด๋Š” ๋ฏธ์„ธ๊ท ์—ด์˜์—ญ์˜ ๋ฐœ๋‹ฌ๊ณผ ํ•จ๊ป˜ ์ฃผ๊ท ์—ด์ด ์„œ์„œํžˆ ๋ฐœ์ƒ๋˜๋ฉด์„œ ์ผ์–ด๋‚œ๋‹ค.6) ์ด๋Š” ์„ ํ˜•ํƒ„์„ฑ ํŒŒ๊ดด์—ญํ•™์˜ ๊ฐ€์ •๊ณผ ๋ชจ์ˆœ๋˜๋ฉฐ ์ด๋ฅผ ํ•ด๊ฒฐํ•˜๊ธฐ ์œ„ํ•ด ๋น„์„ ํ˜• ํŒŒ๊ดด์—ญํ•™์ด ๋„์ž…๋˜์—ˆ๋‹ค. Baลพant5)๋Š” ๋น„์„ ํ˜• ํŒŒ๊ดด์—ญํ•™์— ๊ธฐ๋ฐ˜ํ•˜์—ฌ ๊ธฐํ•˜ํ•™์ ์œผ๋กœ ์œ ์‚ฌํ•œ ๊ณต์‹œ์ฒด์— ๋Œ€ํ•œ ํฌ๊ธฐํšจ๊ณผ๋ฒ•์น™์„ ์ œ์•ˆํ•˜์˜€๋‹ค. ์ดํ›„ Kim and Eo7)๋Š” ํฌ๊ธฐ์™€ ๋ฌด๊ด€ํ•œ ํ•ญ์„ ๋„์ž…ํ•˜์—ฌ Baลพant5)์˜ ํฌ๊ธฐํšจ๊ณผ๋ฒ•์น™์„ ์ˆ˜์ •ํ•˜์˜€๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ ์ง€๊ธˆ๊นŒ์ง€์˜ ํฌ๊ธฐํšจ๊ณผ๋ฒ•์น™์€ ๋ชจ๋‘ ๋ณดํ†ต์ค‘๋Ÿ‰ ์ฝ˜ํฌ๋ฆฌํŠธ์— ๊ธฐ๋ฐ˜ํ•˜๊ณ  ์žˆ์–ด ํŒŒ๊ดดํŠน์„ฑ์ด ๋‹ค๋ฅธ ๊ฒฝ๋Ÿ‰๊ณจ์žฌ ์ฝ˜ํฌ๋ฆฌํŠธ์—์„œ ๊ทธ ํ™œ์šฉ์„ฑ์ด ์˜๋ฌธ์‹œ๋˜๊ณ  ์žˆ๋‹ค.

์ฝ˜ํฌ๋ฆฌํŠธ์˜ ํŒŒ๊ดด๋Š” ์ผ๋ฐ˜์ ์œผ๋กœ ๊ณจ์žฌ ํŒŒ๊ดด, ํŽ˜์ด์ŠคํŠธ ํŒŒ๊ดด ๋ฐ ๊ณจ์žฌ์™€ ํŽ˜์ด์ŠคํŠธ์˜ ๊ณ„๋ฉด ํŒŒ๊ดด ๋“ฑ์œผ๋กœ ๋‚˜๋ˆŒ ์ˆ˜ ์žˆ์œผ๋ฉฐ, ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ์••์ถ•๊ฐ•๋„๊ฐ€ ๋†’์œผ๋ฉด ๊ณจ์žฌ์— ์˜ํ•ด ๊ทธ ๋‚ด๋ ฅ์ด ๊ฒฐ์ •๋œ๋‹ค. ์ฝ˜ํฌ๋ฆฌํŠธ ๋‚ด์˜ ๊ณจ์žฌ๋Š” ์ฝ˜ํฌ๋ฆฌํŠธ ์ „์ฒด ์ฒด์ ์˜ ์•ฝ 60~70%๋กœ ๊ณจ์žฌ์˜ ๊ฐ•๋„์™€ ๊ฐ•์„ฑ์— ์˜ํ•ด ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ์—ญํ•™์  ํŠน์„ฑ์ด ๊ฒฐ์ •๋œ๋‹ค. ์ด์— ACI 3188) ๋ฐ CEB-FIP9) ์„ค๊ณ„๊ธฐ์ค€์—์„œ๋Š” ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ์—ญํ•™์  ํŠน์„ฑ์„ ์˜ˆ์ธกํ•  ๋•Œ ์ฝ˜ํฌ๋ฆฌํŠธ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰์˜ ํ•จ์ˆ˜๋กœ ๊ณจ์žฌ์˜ ํŠน์„ฑ์„ ๋‚˜ํƒ€๋‚ด๊ณ  ์žˆ๋‹ค. ํŠนํžˆ, Sim and Yang10)์€ ์ธ๊ณต๊ฒฝ๋Ÿ‰๊ณจ์žฌ๋ฅผ ์‚ฌ์šฉํ•œ ์ฝ˜ํฌ๋ฆฌํŠธ ์••์ถ•๊ฐ•๋„์˜ ํฌ๊ธฐํšจ๊ณผ์— ๋Œ€ํ•œ ์‹คํ—˜์„ ํ†ตํ•ด ๊ฒฝ๋Ÿ‰๊ณจ์žฌ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ํŒŒ๊ดด์ง„ํ–‰์˜์—ญ์€ ๋ณดํ†ต์ค‘๋Ÿ‰ ์ฝ˜ํฌ๋ฆฌํŠธ๋ณด๋‹ค ์ž‘๊ณ  ๊ณจ์žฌ์˜ ํŒŒ๊ดด์— ์˜ํ•ด ํฌ๊ธฐํšจ๊ณผ์— ๋” ๋ฏผ๊ฐํ•ด ์ง์„ ๋ณด์˜€๋‹ค.

๋ณธ ์—ฐ๊ตฌ์˜ ๋ชฉ์ ์€ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰์„ ๊ณ ๋ คํ•˜์—ฌ ์••์ถ•๊ฐ•๋„์˜ ํฌ๊ธฐํšจ๊ณผ์— ๋Œ€ํ•œ ์˜ˆ์ธก๋ชจ๋ธ์„ ๊ฐœ๋ฐœํ•˜๋Š” ๊ฒƒ์ด๋‹ค. ์ด๋ฅผ ์œ„ํ•ด ๋น„์„ ํ˜• ํŒŒ๊ดด์—ญํ•™์— ๊ธฐ๋ฐ˜ํ•œ Baลพant5)์™€ Kim and Eo7)์˜ ์˜ˆ์ธก๋ชจ๋ธ๋“ค์„ ๋ถ„์„ํ•˜์—ฌ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰์„ ๊ณ ๋ คํ•œ ์••์ถ•๊ฐ•๋„์˜ ํฌ๊ธฐํšจ๊ณผ์— ๋Œ€ํ•œ ์˜ˆ์ธก๋ชจ๋ธ์„ ์ œ์‹œํ•˜์˜€๋‹ค. ๋˜ํ•œ ์˜ˆ์ธก๋ชจ๋ธ์˜ ์ •ํ™•์„ฑ์„ ํ‰๊ฐ€ํ•˜๊ธฐ ์œ„ํ•ด ๊ธฐ์กด ์—ฐ๊ตฌ๊ฒฐ๊ณผ๋“ค์„ ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šคํ™”ํ•˜์—ฌ ์ด ์—ฐ๊ตฌ์—์„œ ์ œ์‹œํ•œ ๋ชจ๋ธ์„ Baลพant5)์™€ Kim and Eo7)์˜ ๋ชจ๋ธ๊ณผ ๋น„๊ตํ•˜์˜€๋‹ค.

2. ๊ธฐ์กด ์••์ถ•๊ฐ•๋„์— ๋Œ€ํ•œ ํฌ๊ธฐํšจ๊ณผ ๋ชจ๋ธ

2.1 Baลพant์˜ ํฌ๊ธฐํšจ๊ณผ ๋ชจ๋ธ

Baลพant๋Š” ์—๋„ˆ์ง€ ํ‰ํ˜•๋ฒ•์น™์„ ๊ธฐ๋ฐ˜์œผ๋กœ ๋น„์„ ํ˜• ํŒŒ๊ดด์—ญํ•™์— ๊ทผ๊ฑฐํ•˜์—ฌ ๊ธฐํ•™ํ•™์ ์œผ๋กœ ์œ ์‚ฌํ•œ ๊ณต์‹œ์ฒด์— ๋Œ€ํ•œ ํฌ๊ธฐํšจ๊ณผ ๋ชจ๋ธ์„ ์‹ (1)๊ณผ ๊ฐ™์ด ์ œ์‹œํ•˜์˜€๋‹ค.

/Resources/kci/JKCI.2015.27.2.169/images/PIC89C5.gif (1)

์—ฌ๊ธฐ์„œ, /Resources/kci/JKCI.2015.27.2.169/images/PIC89E5.gif๋Š” ๊ณต์‹œ์ฒด์˜ ๊ณต์นญํŒŒ๊ดด๊ฐ•๋„(MPa), /Resources/kci/JKCI.2015.27.2.169/images/PIC8A05.gif๋Š” ์••์ถ•๊ฐ•๋„(MPa), /Resources/kci/JKCI.2015.27.2.169/images/PIC8A35.gif๋Š” ๊ณต์‹œ์ฒด์˜ ํฌ๊ธฐ(mm), /Resources/kci/JKCI.2015.27.2.169/images/PIC8A36.gif๋Š” ๊ตต์€๊ณจ์žฌ์˜ ์ตœ๋Œ€์น˜์ˆ˜(mm), /Resources/kci/JKCI.2015.27.2.169/images/PIC8A57.gif์™€ /Resources/kci/JKCI.2015.27.2.169/images/PIC8A67.gif๋Š” ์‹คํ—˜์ƒ์ˆ˜๋ฅผ ๋‚˜ํƒ€๋‚ธ๋‹ค.

์ด ๋ชจ๋ธ์˜ ๊ธฐ๋ณธ๊ฐ€์ •์€ ์ฝ˜ํฌ๋ฆฌํŠธ ๊ณต์‹œ์ฒด์˜ ๊ท ์—ด์ง„์ „์— ํ•„์š”ํ•œ ์—๋„ˆ์ง€๋Š” ๊ท ์—ด๊ธธ์ด(/Resources/kci/JKCI.2015.27.2.169/images/PIC8A97.gif)์™€ ๊ท ์—ด์ง„ํ–‰์˜์—ญ์˜ ๋ฉด์ (/Resources/kci/JKCI.2015.27.2.169/images/PIC8AB7.gif)์— ๋น„๋ก€ํ•œ๋‹ค๋Š” ๊ฒƒ์ด๋‹ค. ๊ท ์—ด์ง„ํ–‰์˜์—ญ์˜ ๋ฉด์ ์€ ๊ท ์—ด๊ธธ์ด์™€ ๊ท ์—ด ํญ(/Resources/kci/JKCI.2015.27.2.169/images/PIC8AC8.gif)์˜ ๊ณฑ์œผ๋กœ ๊ณ„์‚ฐ๋˜๋ฉฐ, ๊ท ์—ด์˜ ํญ์€ ๊ท ์—ด์˜ ์ง„ํ–‰์–‘์ƒ์„ ๋ถ„์„ํ•˜์—ฌ ๊ตต์€๊ณจ์žฌ ์ตœ๋Œ€์น˜์ˆ˜์— ๋น„๋ก€ํ•œ๋‹ค๊ณ  ๊ฐ€์ •ํ–ˆ๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ Baลพant์˜ ํฌ๊ธฐํšจ๊ณผ ๋ชจ๋ธ์€ ๊ณต์‹œ์ฒด์˜ ํฌ๊ธฐ๊ฐ€ ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ ์••์ถ•๊ฐ•๋„๊ฐ€ ์ง€์†์ ์œผ๋กœ ๊ฐ์†Œํ•˜์—ฌ Fig. 1์—์„œ์™€ ๊ฐ™์ด ๊ณต์‹œ์ฒด์˜ ํฌ๊ธฐ๊ฐ€ ๋ฌดํ•œ๋Œ€๋กœ ์ฆ๊ฐ€ํ•˜๋ฉด ์••์ถ•๊ฐ•๋„๊ฐ€ โ€˜0โ€™์— ์ˆ˜๋ ดํ•˜๋Š” ๋ฌธ์ œ๊ฐ€ ๋ฐœ์ƒํ•œ๋‹ค.

/Resources/kci/JKCI.2015.27.2.169/images/PIC8B36.gif

Fig. 1 Comparison of the size effect between Baลพant model and Kim and Eo model

2.2 Kim and Eo์˜ ํฌ๊ธฐํšจ๊ณผ ๋ชจ๋ธ

Kim and Eo๋Š” Baลพant์˜ ๋ชจ๋ธ์„ ๊ธฐ๋ฐ˜์œผ๋กœ ํŠน์„ฑ๊ธธ์ด(/Resources/kci/JKCI.2015.27.2.169/images/PIC8B57.gif) ๋ฐ ๊ณต์‹œ์ฒด์˜ ํฌ๊ธฐ์™€ ๋ฌด๊ด€ํ•œ ํ•ญ(/Resources/kci/JKCI.2015.27.2.169/images/PIC8B77.gif)์„ ๋„์ž…ํ•˜์—ฌ ์ˆ˜์ •๋œ ํฌ๊ธฐํšจ๊ณผ(modified size effect law) ๋ชจ๋ธ์„ ์‹ (2)์™€ ๊ฐ™์ด ์ œ์‹œํ•˜์˜€๋‹ค.

/Resources/kci/JKCI.2015.27.2.169/images/PIC8BC6.gif (2)

์—ฌ๊ธฐ์„œ, /Resources/kci/JKCI.2015.27.2.169/images/PIC8BC7.gif๋Š” ํฌ๊ธฐ์™€ ๋ฌด๊ด€ํ•œ 1.0๋ณด๋‹ค ์ž‘์€ ์ƒ์ˆ˜์ด๋‹ค.

Kim and Eo๋Š” ๊ธฐํ•˜ํ•™์ ์œผ๋กœ ์œ ์‚ฌํ•˜๋ฉฐ ์ƒ๋Œ€๊ท ์—ด๊ธธ์ด์˜ ๋น„๊ฐ€ ์ผ์ •ํ•œ ๊ณต์‹œ์ฒด๋กœ๋ถ€ํ„ฐ, Baลพant์˜ ํฌ๊ธฐํšจ๊ณผ ๋ชจ๋ธ์—์„œ ๋งค๊ฐœ๋ณ€์ˆ˜(/Resources/kci/JKCI.2015.27.2.169/images/PIC8BD8.gif)๋Š” ์ƒ์ˆ˜๊ฐ€ ์•„๋‹ˆ๋ผ /Resources/kci/JKCI.2015.27.2.169/images/PIC8C36.gif์˜ ํ•จ์ˆ˜์ž„์„ ๋ณด์˜€๋‹ค. ์ด๋ฅผ ํ†ตํ•ด ์ตœ์ดˆ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค๋Š”๋ฐ ํ•„์š”ํ•œ ์‘๋ ฅ์œผ๋กœ ์ƒ๊ฐํ•  ์ˆ˜ ์žˆ๋Š” ์ƒ์ˆ˜ํ•ญ์„ ๋„์ž…ํ•˜์˜€๋‹ค. ๋˜ํ•œ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ์ œ์กฐ๋ฅผ ์œ„ํ•ด ์‚ฌ์šฉ๋˜๋Š” ๊ตต์€๊ณจ์žฌ์˜ ์ตœ๋Œ€์น˜์ˆ˜๋Š” 20~70 mm๋กœ ๊ตต์€๊ณจ์žฌ์˜ ์ตœ๋Œ€์น˜์ˆ˜๊ฐ€ ๋ฏธ์„ธ๊ท ์—ด์˜์—ญ์˜ ํญ์— ๋ฏธ์น˜๋Š” ์˜ํ–ฅ์ด ํฌ๊ธฐ ์•Š์Œ์œผ๋กœ ๊ตต์€๊ณจ์žฌ ์ตœ๋Œ€์น˜์ˆ˜์˜ ์˜ํ–ฅ์„ ๋ฌด์‹œํ•˜์˜€๋‹ค. Kim and Eo์˜ ํฌ๊ธฐํšจ๊ณผ ๋ชจ๋ธ์€ Fig. 1๊ณผ ๊ฐ™์ด Baลพant์˜ ํฌ๊ธฐํšจ๊ณผ ๋ชจ๋ธ์„ ํšจ๊ณผ์ ์œผ๋กœ ๊ฐœ์„ ํ•˜์˜€๋‹ค๊ณ  ํŒ๋‹จ๋œ๋‹ค.

3. ๋ชจ๋ธ์˜ ๊ฐœ๋ฐœ

3.1 ๊ธฐ๋ณธ๊ฐ€์ •

๊ฒฝ๋Ÿ‰๊ณจ์žฌ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ์••์ถ•๊ฐ•๋„์— ๋Œ€ํ•œ ํฌ๊ธฐํšจ๊ณผ์˜ ์ด๋ก ๋ชจ๋ธ์„ ์ œ์‹œํ•˜๊ธฐ ์œ„ํ•œ ๊ฐ€์ •์€ ๋‹ค์Œ๊ณผ ๊ฐ™๋‹ค.

โ‘ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ํŒŒ๊ดด๊ฐ€ ์ผ์–ด๋‚  ๋•Œ ์†Œ์š”๋˜๋Š” ์ด์—๋„ˆ์ง€ ํ•ด๋ฐฉ๋Ÿ‰์€ ๊ท ์—ด๊ธธ์ด์˜ ํ•จ์ˆ˜์ด๊ณ , ๊ท ์—ด์ง„ํ–‰์˜์—ญ์˜ ๋ฉด์ ์— ๋น„๋ก€ํ•œ๋‹ค.

โ‘ก์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ท ์—ด์ง„ํ–‰์˜์—ญ์˜ ํญ์€ ๊ตต์€๊ณจ์žฌ์˜ ์ตœ๋Œ€์น˜์ˆ˜์™€ ๋ณดํ†ต ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰(/Resources/kci/JKCI.2015.27.2.169/images/PIC8C66.gif)์„ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰(/Resources/kci/JKCI.2015.27.2.169/images/PIC8CC5.gif)์œผ๋กœ ๋‚˜๋ˆˆ ๊ฐ’(/Resources/kci/JKCI.2015.27.2.169/images/PIC8CF5.gif)์— ๋น„๋ก€ํ•œ๋‹ค. ์—ฌ๊ธฐ์„œ, ๋ณดํ†ต ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰์€ 2,300 kg/m3์„ ์˜๋ฏธํ•œ๋‹ค.

โ‘ข์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ท ์—ด์ง„ํ–‰์˜์—ญ์˜ ๋ฉด์ ์€ ์••์ถ•๊ฐ•๋„์™€ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰์— ๋ฐ˜๋น„๋ก€ํ•œ๋‹ค.

ํ•œํŽธ, ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ท ์—ด์ง„ํ–‰์˜์—ญ์˜ ๋ฉด์ ์€ ๊ท ์—ด์ง„ํ–‰์˜์—ญ์˜ ํญ๊ณผ ๊ธธ์ด์˜ ๊ณฑ์œผ๋กœ ๋‚˜ํƒ€๋‚ผ ์ˆ˜ ์žˆ๋‹ค. ๊ท ์—ด์ง„ํ–‰์˜์—ญ์˜ ํญ์€ ์‚ฌ์šฉ์žฌ๋ฃŒ์™€ ์‹œํ—˜์ฒด์˜ ํ˜•์ƒ ๋“ฑ ๋‹ค์–‘ํ•œ ๋ณ€์ˆ˜์˜ ์˜ํ–ฅ์„ ๋ฐ›๊ธฐ ๋•Œ๋ฌธ์— ์ •ํ™•ํ•œ ํ‰๊ฐ€๊ฐ€ ์–ด๋ ต๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ Baลพant6)๋Š” Fig. 2์— ๋‚˜ํƒ€๋‚ธ ๋ฐ”์™€ ๊ฐ™์ด ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๋ฏธ์„ธ๊ท ์—ด์€ ๊ณจ์žฌ๋ฅผ ํ”ผํ•ด์„œ ๋ฐœ์ƒํ•œ๋‹ค๊ณ  ๊ฐ€์ •ํ•˜์—ฌ ๊ท ์—ด์ง„ํ–‰์˜์—ญ์˜ ํญ์„ ๊ตต์€๊ณจ์žฌ ์ตœ๋Œ€์น˜์ˆ˜(/Resources/kci/JKCI.2015.27.2.169/images/PIC8D54.gif)์˜ ํ•จ์ˆ˜๋กœ ์ด์ƒํ™”ํ•˜์˜€๋‹ค. ๋˜ํ•œ Kim and Eo11)๋Š” Blank and McNamara์˜ ์‹คํ—˜๊ฒฐ๊ณผ2)๋ฅผ ๋ถ„์„ํ•˜์—ฌ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ์••์ถ•๊ฐ•๋„๊ฐ€ ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ ๊ท ์—ด์ง„ํ–‰์˜์—ญ์ด ์ž‘์•„์ง์œผ๋กœ ๊ท ์—ด์ง„ํ–‰์˜์—ญ์˜ ํญ์€ ๊ตต์€๊ณจ์žฌ์˜ ์ตœ๋Œ€์น˜์ˆ˜ ๋ฟ๋งŒ ์•„๋‹ˆ๋ผ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ์••์ถ•๊ฐ•๋„์— ์˜ํ–ฅ์ด ์žˆ์Œ์„ ๋ณด์˜€๋‹ค.

์ฝ˜ํฌ๋ฆฌํŠธ์—์„œ ๊ท ์—ด์ง„ํ–‰์˜์—ญ์˜ ํญ์€ Fig. 2์—์„œ์™€ ๊ฐ™์ด ์ฝ˜ํฌ๋ฆฌํŠธ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰์˜ ํ•จ์ˆ˜๋กœ ๋‚˜ํƒ€๋‚ผ ์ˆ˜ ์žˆ๋‹ค. ๊ฒฝ๋Ÿ‰๊ณจ์žฌ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ท ์—ด์ง„ํ–‰์˜์—ญ์˜ ํญ์€ ์ผ๋ฐ˜์ ์œผ๋กœ ๋ณดํ†ต์ค‘๋Ÿ‰ ์ฝ˜ํฌ๋ฆฌํŠธ๋ณด๋‹ค ์ž‘์€๋ฐ, ์ด๋Š” ๊ณจ์žฌ์˜ ๊ฐ•๋„์— ๊ธฐ์ธํ•œ ๊ฒƒ์œผ๋กœ ๋ณดํ†ต์ค‘๋Ÿ‰ ์ฝ˜ํฌ๋ฆฌํŠธ์—์„œ ๊ท ์—ด์ด ๊ณจ์žฌ๋ฅผ ๋งŒ๋‚˜๋ฉด ๊ฐ•๋„๊ฐ€ ํฐ ๊ณจ์žฌ๋ฅผ ํ”ผํ•ด ๊ณจ์žฌ์™€ ์‹œ๋ฉ˜ํŠธ ํŽ˜์ด์ŠคํŠธ์˜ ๊ณ„๋ฉด์„ ๋”ฐ๋ผ ์„ฑ์žฅํ•œ๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ ๊ฒฝ๋Ÿ‰๊ณจ์žฌ ์ฝ˜ํฌ๋ฆฌํŠธ๋Š” ๊ท ์—ด์ด ๊ฒฝ๋Ÿ‰๊ณจ์žฌ์˜ ๋‚ฎ์€ ๊ฐ•๋„๋กœ ์ธํ•ด ํŒŒ๊ดด ์‹œ ๊ณจ์žฌ๋ฅผ ๊ด€ํ†ตํ•˜์—ฌ ์„ฑ์žฅํ•˜๊ธฐ ๋•Œ๋ฌธ์ด๋‹ค.

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(a) light weight concrete

(b) normal weight concrete

Fig. 2 The width of the fracture process zone in concrete

3.2 ๋ชจ๋ธ์˜ ์ œ์•ˆ

์ฝ˜ํฌ๋ฆฌํŠธ๊ฐ€ ๋ณ€ํ˜•๋˜๊ธฐ ์œ„ํ•ด ํ•„์š”ํ•œ ์—๋„ˆ์ง€(/Resources/kci/JKCI.2015.27.2.169/images/PIC8E40.gif)๋Š” ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ์ฒด์  ๋ฐ ์—๋„ˆ์ง€ ๋ฐ€๋„(/Resources/kci/JKCI.2015.27.2.169/images/PIC8E60.gif)์— ๋น„๋ก€ํ•˜๋ฏ€๋กœ ์‹ (3)๊ณผ ๊ฐ™์ด ๋‚˜ํƒ€๋‚ผ ์ˆ˜ ์žˆ๋‹ค.

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์—ฌ๊ธฐ์„œ, /Resources/kci/JKCI.2015.27.2.169/images/PIC8EA1.gif๋Š” ์ฝ˜ํฌ๋ฆฌํŠธ ๊ณต์‹œ์ฒด์˜ ๋‹จ๋ฉด์ ์œผ๋กœ /Resources/kci/JKCI.2015.27.2.169/images/PIC8EC1.gif, /Resources/kci/JKCI.2015.27.2.169/images/PIC8EE1.gif๋Š” ๊ณต์‹œ์ฒด ๋‹จ๋ฉดํ˜•ํƒœ์— ๋Œ€ํ•œ ๊ณ„์ˆ˜๋กœ์„œ ์›ํ˜•๋‹จ๋ฉด์€ /Resources/kci/JKCI.2015.27.2.169/images/PIC8F11.gif, ๊ฐํ˜•๋‹จ

๋ฉด์€ 1.0 ์ด๋‹ค. /Resources/kci/JKCI.2015.27.2.169/images/PIC8F22.gif๋Š” ์ฝ˜ํฌ๋ฆฌํŠธ ๊ณต์‹œ์ฒด์˜ ๋†’์ด, /Resources/kci/JKCI.2015.27.2.169/images/PIC8F61.gif๋Š”

๋ณด์ •๊ณ„์ˆ˜๋กœ์„œ ๊ท ์—ด๊ธธ์ด์— ๊ด€๋ จ๋œ /Resources/kci/JKCI.2015.27.2.169/images/PIC8F91.gif์™€ ๊ท ์—ด์ง„ํ–‰

์˜์—ญ์˜ ๋ฉด์ ์— ๊ด€๋ จ๋œ /Resources/kci/JKCI.2015.27.2.169/images/PIC8FD1.gif์˜ ํ•ฉ์„ฑํ•จ์ˆ˜์ด๋‹ค. ์—ฌ๊ธฐ

์„œ, /Resources/kci/JKCI.2015.27.2.169/images/PIC9010.gif๋Š” ๊ท ์—ด์ง„ํ–‰์˜์—ญ์˜ ํญ์ด๋‹ค.

Baลพant and Oh๊ฐ€ ์ œ์•ˆํ•œ ๊ท ์—ด๋  ์ด๋ก 12)์— ๋”ฐ๋ฅด๋ฉด, Fig. 3์— ๋‚˜ํƒ€๋‚ธ ๋ฐ”์™€ ๊ฐ™์ด ๋ฏธ์„ธ๊ท ์—ด์„ ๊ณ ๋ คํ•œ ์ด์‚ฐํ™”๋œ ์‘๋ ฅ-๋ณ€ํ˜•๋ฅ  ๊ด€๊ณ„๋กœ๋ถ€ํ„ฐ ๊ท ์—ด์ด ์ง„์ „๋˜๊ธฐ ์œ„ํ•œ ์กฐ๊ฑด์€ ์‹ (4)์™€ ๊ฐ™๋‹ค.

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Fig. 3 Idealized tensile stress-strain curve of the concrete

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์—ฌ๊ธฐ์„œ, /Resources/kci/JKCI.2015.27.2.169/images/PIC910D.gif๋Š” ๋‹จ์œ„๊ธธ์ด์˜ ๊ท ์—ด์„ ์ง„์ „์‹œํ‚ค๋Š” ๋ฐ ํ•„์š”ํ•œ ํŒŒ๊ดด์—๋„ˆ์ง€, /Resources/kci/JKCI.2015.27.2.169/images/PIC913D.gif์€ ๊ท ์—ด๋Œ€ ๋‚ด์˜ ๊ท ์—ด๊ฐœ์ˆ˜, /Resources/kci/JKCI.2015.27.2.169/images/PIC913E.gif์€ ๊ณต์‹œ์ฒด์˜ ํ˜•์ƒ๋น„, /Resources/kci/JKCI.2015.27.2.169/images/PIC916E.gif๋Š” ๊ท ์—ด๊ธธ์ด, /Resources/kci/JKCI.2015.27.2.169/images/PIC917E.gif๊ณผ /Resources/kci/JKCI.2015.27.2.169/images/PIC919F.gif๋Š” ์‹คํ—˜์ƒ์ˆ˜๋ฅผ ๋‚˜ํƒ€๋‚ธ๋‹ค.

์—๋„ˆ์ง€ ํ‰ํ˜•์กฐ๊ฑด์— ์˜ํ•ด ๊ท ์—ด์ง„์ „์„ ์œ„ํ•œ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๋ณ€ํ˜•์—๋„ˆ์ง€๋Š” ๊ท ์—ด๋Œ€์—์„œ ๊ท ์—ด๋ฐœ์ƒ์„ ์œ„ํ•ด ํ•„์š”ํ•œ ์—๋„ˆ์ง€์™€ ๊ฐ™์œผ๋ฉฐ, ์ด๋Š” ์‹ (5)์™€ ๊ฐ™์ด ๋‚˜ํƒ€๋‚ผ ์ˆ˜ ์žˆ๋‹ค.

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์‹ (3)๊ณผ ์‹ (4)๋ฅผ ์‹ (5)์— ๋Œ€์ž…ํ•˜์—ฌ /Resources/kci/JKCI.2015.27.2.169/images/PIC923D.gif์— ๋Œ€ํ•ด ์ •๋ฆฌํ•˜๋ฉด, ์‹ (6)๊ณผ ๊ฐ™์ด ๋œ๋‹ค.

/Resources/kci/JKCI.2015.27.2.169/images/PIC92AB.gif

/Resources/kci/JKCI.2015.27.2.169/images/PIC931A.gif (6)

์‹ (6)์— ๋‚˜ํƒ€๋‚œ ๋‘ ๊ฐœ์˜ ๋ณ€์ˆ˜๊ฐ€ ๊ฒฐํ•ฉ๋œ ํ•ฉ์„ฑํ•จ์ˆ˜์˜ ๋ฏธ๋ถ„์„ ๊ณ„์‚ฐํ•˜๊ธฐ ์œ„ํ•œ chain rule์€ ์‹ (7)๊ณผ ๊ฐ™๋‹ค.

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/Resources/kci/JKCI.2015.27.2.169/images/PIC9406.gif๊ณผ /Resources/kci/JKCI.2015.27.2.169/images/PIC9436.gif๋กœ ์น˜ํ™˜ํ•˜๋ฉด ์‹ (7)์€ ์‹ (8)๊ณผ ๊ฐ™

์ด ๋œ๋‹ค.

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์‹ (8)์„ ์ด์šฉํ•˜์—ฌ ์‹ (6)์„ ์ •๋ฆฌํ•˜๋ฉด ์‹ (9)์™€ ๊ฐ™๋‹ค.

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๊ท ์—ด๋  ์ด๋ก 12)์— ์˜ํ•˜๋ฉด /Resources/kci/JKCI.2015.27.2.169/images/PIC9533.gif๋Š” /Resources/kci/JKCI.2015.27.2.169/images/PIC95A1.gif์™€ ๊ฐ™์œผ๋ฏ€

๋กœ, ์ด๋ฅผ ์‹ (9)์— ๋Œ€์ž…ํ•˜๊ณ  ์ •๋ฆฌํ•˜๋ฉด ์‹ (10)๊ณผ ๊ฐ™์ด ๋œ๋‹ค.

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๊ฐ€์ •์‚ฌํ•ญ์—์„œ ๊ท ์—ด์ง„ํ–‰์˜์—ญ์˜ ํญ(/Resources/kci/JKCI.2015.27.2.169/images/PIC9837.gif)์€ /Resources/kci/JKCI.2015.27.2.169/images/PIC98A5.gif์ด

๋ฉฐ, ํ˜•์ƒ๋น„(/Resources/kci/JKCI.2015.27.2.169/images/PIC98D5.gif)๋Š” /Resources/kci/JKCI.2015.27.2.169/images/PIC9914.gif์ด๋‹ค. ์ด๋ฅผ ์‹ (10)์— ๋Œ€์ž…ํ•˜์—ฌ ์ •๋ฆฌํ•˜๋ฉด ์‹ (11)๊ณผ ๊ฐ™๋‹ค.

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์‹ (11)์„ /Resources/kci/JKCI.2015.27.2.169/images/PIC9ACD.gif์— ๋Œ€ํ•ด์„œ ์ •๋ฆฌํ•˜๊ณ  ๋‹จ์ˆœํ™”ํ•˜๋ฉด ์‹ (12)์™€ ๊ฐ™์ด ๋œ๋‹ค.

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์—ฌ๊ธฐ์„œ, /Resources/kci/JKCI.2015.27.2.169/images/PIC9B5B.gif์€ /Resources/kci/JKCI.2015.27.2.169/images/PIC9B7C.gif์ด๊ณ  /Resources/kci/JKCI.2015.27.2.169/images/PIC9BDA.gif์€ /Resources/kci/JKCI.2015.27.2.169/images/PIC9C2A.gif์„ ๋‚˜ํƒ€๋‚ธ๋‹ค.

Kim and Eo7)๋Š” ๋ณดํ†ต์ค‘๋Ÿ‰ ์ฝ˜ํฌ๋ฆฌํŠธ์—์„œ ๊ตต์€๊ณจ์žฌ์˜ ์ตœ๋Œ€์น˜์ˆ˜๊ฐ€ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ท ์—ดํญ์ด ๋ฏธ์น˜๋Š” ์˜ํ–ฅ์ด ๋ฏธ๋ฏธํ•จ์„ ๋ณด์˜€๋‹ค. ํŠนํžˆ, ๊ฒฝ๋Ÿ‰๊ณจ์žฌ ์ฝ˜ํฌ๋ฆฌํŠธ์—์„œ๋Š” ๊ฒฝ๋Ÿ‰๊ณจ์žฌ๋ฅผ ๊ด€ํ†ตํ•˜์—ฌ ๊ท ์—ด์ด ์ง„์ „๋˜๋ฏ€๋กœ ๊ตต์€๊ณจ์žฌ ์ตœ๋Œ€์น˜์ˆ˜์˜ ์˜ํ–ฅ์„ ๋ฌด์‹œํ•  ์ˆ˜ ์žˆ๋‹ค. ์ด์— ์‹ (12)์—์„œ ๊ตต์€๊ณจ์žฌ ์ตœ๋Œ€์น˜์ˆ˜์˜ ์˜ํ–ฅ์„ ๋ฌด์‹œํ•˜๊ณ  ์ •๋ฆฌํ•˜๋ฉด ์‹ (13)๊ณผ ๊ฐ™๋‹ค.

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์—ฌ๊ธฐ์„œ, /Resources/kci/JKCI.2015.27.2.169/images/PIC9CA9.gif๋Š” ์‹คํ—˜์ƒ์ˆ˜์ด๋‹ค.

์‹ (13)์€ Baลพant์˜ ํฌ๊ธฐํšจ๊ณผ ๋ชจ๋ธ๊ณผ ๊ฐ™์€ ํ˜•์‹์œผ๋กœ ๊ณต์‹œ์ฒด์˜ ํฌ๊ธฐ๊ฐ€ ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ ์ง€์†์ ์œผ๋กœ ์••์ถ•๊ฐ•๋„๊ฐ€ ๊ฐ์†Œํ•˜๊ฒŒ ๋˜์–ด ์žˆ๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ Kim and Eo๊ฐ€ ์ œ์‹œํ•œ ๊ฒƒ์ฒ˜๋Ÿผ ์ฝ˜ํฌ๋ฆฌํŠธ ๊ณต์‹œ์ฒด์˜ ํฌ๊ธฐ๊ฐ€ ์ฆ๊ฐ€ํ•ด๋„ ์••์ถ•๊ฐ•๋„๊ฐ€ ๋” ์ด์ƒ ๊ฐ์†Œํ•˜์ง€ ์•Š๊ณ  ์ˆ˜๋ ดํ•˜๋Š” ๋ถ€๋ถ„์ด ๋‚˜ํƒ€๋‚˜๊ฒŒ ๋œ๋‹ค. ์ด๋ฅผ ๊ณ ๋ คํ•˜์—ฌ ์‹ (13)์„ ์ˆ˜์ •ํ•˜๋ฉด ์‹ (14)์™€ ๊ฐ™์ด ๋œ๋‹ค.

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์—ฌ๊ธฐ์„œ, /Resources/kci/JKCI.2015.27.2.169/images/PIC9D08.gif๋Š” ์ฝ˜ํฌ๋ฆฌํŠธ ๊ณต์‹œ์ฒด์˜ ํฌ๊ธฐ์™€ ๋ฌด๊ด€ํ•˜๊ฒŒ ๊ณต์‹œ์ฒด์˜ ์ดˆ๊ธฐ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค๋Š” ๋ฐ ํ•„์š”ํ•œ ์‘๋ ฅ์ด๋‹ค.

4. ๋ชจ๋ธ์˜ ๊ฒ€์ฆ

4.1 ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค ๊ตฌ์ถ•

์ด ์—ฐ๊ตฌ์—์„œ๋Š” ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ํฌ๊ธฐํšจ๊ณผ์— ๋Œ€ํ•œ ๊ธฐ์กด์—ฐ๊ตฌ ๊ฒฐ๊ณผ๋“ค1,2,13-18)์„ ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค๋กœ ๊ตฌ์ถ•ํ•˜์˜€๋‹ค. ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค์—์„œ ์ •๋ณด๊ฐ€ ์ œ๊ณต๋˜์ง€ ์•Š์€ ๊ณต์‹œ์ฒด๋“ค์˜ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰์€ ์ œ์‹œ๋œ ๋ฐฐํ•ฉํ‘œ๋ฅผ ์ด์šฉํ•˜์—ฌ ACI 3188)์— ์ œ์‹œ๋œ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰ ์˜ˆ์ธก๋ชจ๋ธ์— ์˜ํ•ด ๊ณ„์‚ฐํ•˜์˜€๋‹ค. ๊ตฌ์ถ•๋œ ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค์˜ ์ฃผ์š”๋ณ€์ˆ˜๋“ค์˜ ๋ถ„ํฌ๋ฅผ Fig. 4์— ๋‚˜ํƒ€๋‚ด์—ˆ๋‹ค. ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค๋Š” ๋ณดํ†ต์ค‘๋Ÿ‰ ์ฝ˜ํฌ๋ฆฌํŠธ 1449๊ฐœ, ๊ฒฝ๋Ÿ‰๊ณจ์žฌ ์ฝ˜ํฌ๋ฆฌํŠธ 251๊ฐœ๋กœ ์ด 1700๊ฐœ๊ฐ€ ์ˆ˜์ง‘๋˜์—ˆ๋‹ค. ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค์˜ ์••์ถ•๊ฐ•๋„ ๋ฒ”์œ„๋Š” 6.6~128 MPa์ด๋ฉฐ, ์••์ถ•๊ฐ•๋„ 40 MPa ์ดํ•˜๊ฐ€ ์•ฝ 67%๋ฅผ ์ฐจ์ง€ํ•˜์˜€๋‹ค. ๊ณต์‹œ์ฒด์˜ ํฌ๊ธฐ๋Š” ๋ณดํ†ต์ค‘๋Ÿ‰ ์ฝ˜ํฌ๋ฆฌํŠธ์—์„œ 37.5~915 mm, ๊ฒฝ๋Ÿ‰๊ณจ์žฌ ์ฝ˜ํฌ๋ฆฌํŠธ๋Š” 50~400 mm ๋ฒ”์œ„์— ์žˆ์—ˆ๋‹ค. ์ „์ฒด ๊ณต์‹œ์ฒด ์ค‘์— 300 mm ์ด์ƒ์˜ ๋Œ€ํ˜• ๊ณต์‹œ์ฒด๋Š” 73๊ฐœ๋กœ ์•ฝ 4.3%๋ฅผ ์ฐจ์ง€ํ•˜๊ณ  ์žˆ์œผ๋ฉฐ, ๋Œ€๋ถ€๋ถ„์ด 100~200 mm ๋ฒ”์œ„์— ์กด์žฌํ•œ๋‹ค. ๊ณต์‹œ์ฒด์˜ ํ˜•์ƒ๋น„๋Š” 0.5~4.0๊นŒ์ง€ ๋‹ค์–‘ํ•˜๋ฉฐ, ์ „์ฒด ๊ณต์‹œ์ฒด์˜ ์•ฝ 55%๋Š” ํ˜•์ƒ๋น„ 2.0์˜ ํ‘œ์ค€๊ณต์‹œ์ฒด์˜€๋‹ค. ๊ตต์€๊ณจ์žฌ์˜ ์ตœ๋Œ€์น˜์ˆ˜๋Š” 4.7~228.6 mm ๋ฒ”์œ„์— ์žˆ์œผ๋ฉฐ, ์ „์ฒด ๊ณต์‹œ์ฒด์˜ ์•ฝ 97%๋Š” ๊ตต์€๊ณจ์žฌ ์ตœ๋Œ€์น˜์ˆ˜๊ฐ€ 40 mm ์ดํ•˜์— ๋ถ„ํฌํ•˜์˜€๋‹ค. ๊ณต์‹œ์ฒด์˜ ๋†’์ด๋Š” 38.1~ 1828.8 mm๊นŒ์ง€ ๋„“์€ ๋ถ„ํฌ๋ฅผ ๋ณด์˜€๋‹ค. ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰์€ 1570~2510 kg/m3 ๋ฒ”์œ„์— ์žˆ์œผ๋ฉฐ, ์ „์ฒด ๊ณต์‹œ์ฒด์˜ ์•ฝ 62%๋Š” ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰ 2300~2400 kg/m3์˜ ๋ณดํ†ต์ค‘๋Ÿ‰ ์ฝ˜ํฌ๋ฆฌํŠธ์ด๋‹ค.

4.2 ๊ธฐ์กด ์—ฐ๊ตฌ๊ฒฐ๊ณผ์™€์˜ ๋น„๊ต

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Fig. 4 Distribution of values with main parameter in the database. (NWC: normal weight concrete, SLWC; sand light-weight concrete, ALWC; all light-weight concrete)

๊ตฌ์ถ•๋œ ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค๋ฅผ ์ด์šฉํ•œ ๋น„์„ ํ˜• ํšŒ๊ท€๋ถ„์„์„ ํ†ตํ•ด ๊ธฐ์กด ์˜ˆ์ธก๋ชจ๋ธ๋“ค๊ณผ ์‹ (14)์— ๋Œ€ํ•œ ์‹คํ—˜์ƒ์ˆ˜๋“ค์„ ๊ฒฐ์ •ํ•˜์—ฌ Table 1์— ๋‚˜ํƒ€๋‚ด์—ˆ๊ณ  ์ด ์‹คํ—˜์ƒ์ˆ˜๋“ค์„ ์ด์šฉํ•˜์—ฌ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰์— ๋”ฐ๋ฅธ ๊ณต์‹œ์ฒด ํฌ๊ธฐ(d)์™€ ์••์ถ•๊ฐ•๋„ ๋น„์˜ ๊ด€๊ณ„๋ฅผ Fig. 5์— ๋‚˜ํƒ€๋‚ด์—ˆ๋‹ค. ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰์ด 2350 kg/m3์—์„œ 1650 kg/m3์œผ๋กœ ๊ฐ์†Œํ•จ์— ๋”ฐ๋ผ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ์••์ถ•๊ฐ•๋„์— ๋Œ€ํ•œ ํฌ๊ธฐํšจ๊ณผ๊ฐ€ ๋” ํ™•์—ฐํ•˜์˜€๋‹ค. ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰์ธ 1650ยฑ50 kg/m3์—์„œ ์ฝ˜ํฌ๋ฆฌํŠธ ๊ณต์‹œ์ฒด์˜ ํฌ๊ธฐ๊ฐ€ 300 mm์ผ ๋•Œ /Resources/kci/JKCI.2015.27.2.169/images/PICA1F1.gif๋Š” ํ‰๊ท  0.82์ •๋„์˜€์ง€๋งŒ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰์ด 2350ยฑ50 kg/m3์—์„œ ์ฝ˜ํฌ๋ฆฌํŠธ ๊ณต์‹œ์ฒด์˜ ํฌ๊ธฐ๊ฐ€ 300 mm์ผ ๋•Œ์˜ /Resources/kci/JKCI.2015.27.2.169/images/PICA27F.gif๋Š” ํ‰๊ท  0.87๋กœ 1.06๋ฐฐ ๋†’์•˜๋‹ค. ์ด๋Š” Fig. 2์— ๋‚˜ํƒ€๋‚ธ ๋ฐ”์™€ ๊ฐ™์ด ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰์ด ์ฝ˜ํฌ๋ฆฌํŠธ ํŒŒ๊ดด์˜์—ญ์˜ ํญ์„ ๊ฒฐ์ •ํ•˜๊ธฐ ๋•Œ๋ฌธ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค. ์ด ๊ทธ๋ฆผ์œผ๋กœ๋ถ€ํ„ฐ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰์„ ๊ณ ๋ คํ•œ ๋ณธ ์—ฐ๊ตฌ์˜ ์˜ˆ์ธก๋ชจ๋ธ์ด Baลพant์™€ Kim and Eo์˜ ์˜ˆ์ธก๋ชจ๋ธ๋ณด๋‹ค ์‹คํ—˜๊ฒฐ๊ณผ๋ฅผ ๋” ์ž˜ ์˜ˆ์ธกํ•˜๊ณ  ์žˆ์Œ์„ ์•Œ ์ˆ˜ ์žˆ๋‹ค.

์••์ถ•๊ฐ•๋„์˜ ํฌ๊ธฐํšจ๊ณผ์— ๋Œ€ํ•ด ๊ตฌ์ถ•๋œ ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค์˜ ์‹คํ—˜๊ฒฐ๊ณผ์™€ ์œ„์—์„œ ๋ถ„์„๋œ ์˜ˆ์ธก๋ชจ๋ธ๋“ค์˜ ๋น„๊ต๋ฅผ Fig. 6์—, ๊ทธ๋ฆฌ๊ณ  ์‹คํ—˜๊ฒฐ๊ณผ์— ๋Œ€ํ•œ ์˜ˆ์ธก๋ชจ๋ธ๋“ค์˜ ํ‰๊ท (/Resources/kci/JKCI.2015.27.2.169/images/PICA2CE.gif), ํ‘œ์ค€ํŽธ์ฐจ(/Resources/kci/JKCI.2015.27.2.169/images/PICA37B.gif), ๋ณ€๋™๊ณ„์ˆ˜(/Resources/kci/JKCI.2015.27.2.169/images/PICA3BA.gif) ๋ฐ ์—๋Ÿฌ๊ณ„์ˆ˜(/Resources/kci/JKCI.2015.27.2.169/images/PICA429.gif)๋ฅผ Table 1์— ๋‚˜ํƒ€๋‚ด์—ˆ๋‹ค. Baลพant์˜ ์˜ˆ์ธก๋ชจ๋ธ์€ /Resources/kci/JKCI.2015.27.2.169/images/PICA439.gif๋ฅผ ์ฃผ์š” ๋ณ€์ˆ˜๋กœ ๊ตฌ์„ฑ๋˜์–ด ์žˆ์œผ๋ฉฐ, /Resources/kci/JKCI.2015.27.2.169/images/PICA469.gif๊ฐ€ 10 ์ดํ•˜์—์„œ๋Š” ๋‹จ๋ถ€๊ตฌ์†ํšจ๊ณผ๋กœ ์ธํ•ด /Resources/kci/JKCI.2015.27.2.169/images/PICA4B8.gif์˜ ๋ฒ”์œ„๊ฐ€ ๋„“๊ฒŒ ๋ถ„ํฌํ•˜๊ณ  ์žˆ์—ˆ๋‹ค. /Resources/kci/JKCI.2015.27.2.169/images/PICA527.gif๊ฐ€ 10 ์ด์ƒ์—์„œ /Resources/kci/JKCI.2015.27.2.169/images/PICA576.gif๋Š” ์ผ๋ฐ˜์ ์œผ๋กœ ๋ณดํ†ต์ค‘๋Ÿ‰ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ฐ’์ด ๊ฒฝ๋Ÿ‰๊ณจ์žฌ ์ฝ˜ํฌ๋ฆฌํŠธ๋ณด๋‹ค ์ปธ์œผ๋ฉฐ, ๊ทธ ๊ฒฝํ–ฅ์€ ํ˜•์ƒ๋น„๊ฐ€ ๊ฐ์†Œํ• ์ˆ˜๋ก ์ฆ๊ฐ€ํ•˜์˜€๋‹ค. Baลพant์˜ ์˜ˆ์ธก๋ชจ๋ธ์€ ์‹คํ—˜๊ฒฐ๊ณผ์— ๋Œ€ํ•œ ์˜ˆ์ธก๊ฐ’์˜ ํ‰๊ท ์€ ๋ณดํ†ต์ค‘๋Ÿ‰ ์ฝ˜ํฌ๋ฆฌํŠธ์™€ ๊ฒฝ๋Ÿ‰๊ณจ์žฌ ์ฝ˜ํฌ๋ฆฌํŠธ์—์„œ ๊ฐ๊ฐ 1.050๊ณผ 1.060์ด์—ˆ๋‹ค. ๋˜ํ•œ ์—๋Ÿฌ๊ณ„์ˆ˜๋Š” ๊ฒฝ๋Ÿ‰๊ณจ์žฌ ์ฝ˜ํฌ๋ฆฌํŠธ๊ฐ€ ๋ณดํ†ต์ค‘๋Ÿ‰ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ์•ฝ 65%์ •๋„๋กœ ๋‚ฎ์•˜๋‹ค. ์ด๋Š” ๊ฒฝ๋Ÿ‰๊ณจ์žฌ ์ฝ˜ํฌ๋ฆฌํŠธ์— ๋Œ€ํ•œ ๋ฐ์ดํ„ฐ์˜ ์ˆ˜๊ฐ€ ๋ณดํ†ต์ค‘๋Ÿ‰ ์ฝ˜ํฌ๋ฆฌํŠธ๋ณด๋‹ค ์ ์—ˆ๊ธฐ ๋•Œ๋ฌธ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค. ๊ณต์‹œ์ฒด์˜ ํฌ๊ธฐ๋ฅผ ์ œ์™ธํ•œ ๋ชจ๋“  ๋ณ€์ˆ˜๋ฅผ ์‹คํ—˜์ƒ์ˆ˜๋กœ ์ œ์‹œํ•˜๊ณ  ์žˆ๋Š” Kim and Eo์˜ ์˜ˆ์ธก๋ชจ๋ธ์€ ๊ณต์‹œ์ฒด ํฌ๊ธฐ๊ฐ€ 200 mm ์ดํ•˜์—์„œ ํ˜•์ƒ๋น„๊ฐ€ ์ž‘์„์ˆ˜๋ก ๋” ๋„“์€ ๋ถ„ํฌ๋ฅผ ๋ณด์˜€๋‹ค. ์ด๋Š” ํ˜•์ƒ๋น„๊ฐ€ ์ž‘์„์ˆ˜๋ก ๋‹จ๋ถ€๊ตฌ์†์˜ ์˜ํ–ฅ์ด ๋” ๋ฏผ๊ฐํ•˜๊ฒŒ ๋‚˜ํƒ€๋‚˜๊ธฐ ๋•Œ๋ฌธ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค. Kim and Eo์˜ ์˜ˆ์ธก๋ชจ๋ธ์€ ์ „๋ฐ˜์ ์œผ๋กœ ์‹คํ—˜๊ฒฐ๊ณผ๋ฅผ ๊ณผ์†Œํ‰๊ฐ€ํ•˜๊ณ  ์žˆ๋‹ค. Kim and Eo์˜ ์˜ˆ์ธก๋ชจ๋ธ์€ ์‹คํ—˜๊ฒฐ๊ณผ์— ๋Œ€ํ•œ ์˜ˆ์ธก๊ฐ’์˜ ํ‰๊ท ์ด ๋ณดํ†ต์ค‘๋Ÿ‰ ์ฝ˜ํฌ๋ฆฌํŠธ์—์„œ 1.010์œผ๋กœ ๊ฒฝ๋Ÿ‰๊ณจ์žฌ ์ฝ˜ํฌ๋ฆฌํŠธ๋ณด๋‹ค ๋” ์ž˜ ์˜ˆ์ธกํ•˜์˜€์œผ๋ฉฐ, ์—๋Ÿฌ๊ณ„์ˆ˜๋Š” 0.220์œผ๋กœ ๊ตต์€๊ณจ์žฌ ์ตœ๋Œ€์น˜์ˆ˜๋ฅผ ๋ณ€์ˆ˜๋กœ ์‚ฌ์šฉํ•œ Baลพant์˜ ์˜ˆ์ธก๋ชจ๋ธ๋ณด๋‹ค ๋” ์šฐ์ˆ˜ํ•˜์˜€๋‹ค. ์ด๋Š” ๊ตต์€๊ณจ์žฌ์˜ ์ตœ๋Œ€์น˜์ˆ˜๋ณด๋‹ค๋Š” ๋˜ ๋‹ค๋ฅธ ๋ณ€์ˆ˜๊ฐ€ ํฌ๊ธฐํšจ๊ณผ์— ๋” ํฐ ์˜ํ–ฅ์„ ๋ฏธ์น˜๊ธฐ ๋•Œ๋ฌธ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค.

์ด ์—ฐ๊ตฌ์—์„œ ์ œ์•ˆ๋œ ์˜ˆ์ธก๋ชจ๋ธ์€ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰์„ ํฌํ•จํ•œ /Resources/kci/JKCI.2015.27.2.169/images/PICC4EA.gif๋ฅผ ์ฃผ์š” ๋ณ€์ˆ˜๋กœ ํฌํ•จํ•˜๊ณ  ์žˆ๋‹ค. /Resources/kci/JKCI.2015.27.2.169/images/PICC5C6.gif์ด ์ฆ๊ฐ€ํ• ์ˆ˜๋ก /Resources/kci/JKCI.2015.27.2.169/images/PICD40F.gif๋Š” ๊ฐ์†Œํ•˜์˜€์œผ๋ฉฐ, ๊ทธ ๊ฒฝํ–ฅ์€ ํ˜•์ƒ๋น„๊ฐ€ ํด์ˆ˜๋ก ์ฆ๊ฐ€ํ•˜์˜€๋‹ค. /Resources/kci/JKCI.2015.27.2.169/images/PICD4CC.gif๋Š” /Resources/kci/JKCI.2015.27.2.169/images/PICD53A.gif๊ฐ€ 200 ์ดํ•˜์—์„œ๋Š” ๋„“์€ ๋ถ„ํฌ๋ฅผ ๋ณด์˜€์ง€๋งŒ ๊ทธ ์ด์ƒ์—์„œ๋Š” ์ข์€ ์˜์—ญ์—์„œ ์ผ์ •ํ•œ ๊ฒฝํ–ฅ์„ ๋ณด์˜€๋‹ค. ํ˜•์ƒ๋น„๊ฐ€ 2.0 ์ดํ•˜์ธ ๊ณต์‹œ์ฒด์˜ /Resources/kci/JKCI.2015.27.2.169/images/PICD589.gif๋Š” ๊ทธ ์ด์ƒ์˜ ๊ณต์‹œ์ฒด๋ณด๋‹ค ๋†’์•˜์œผ๋ฉฐ, ๋ณธ ์—ฐ๊ตฌ๊ฒฐ๊ณผ์˜ ์˜ˆ์ธก๋ชจ๋ธ์€ ์ด๋ฅผ ์ž˜ ๋ฐ˜์˜ํ•˜๊ณ  ์žˆ์—ˆ๋‹ค. ๋ณธ ์—ฐ๊ตฌ์˜ ์˜ˆ์ธก๋ชจ๋ธ์€ ์‹คํ—˜๊ฒฐ๊ณผ์— ๋Œ€ํ•œ ์˜ˆ์ธก๊ฐ’์˜ ํ‰๊ท ์œผ๋กœ ๋ณดํ†ต์ค‘๋Ÿ‰ ์ฝ˜ํฌ๋ฆฌํŠธ์™€ ๊ฒฝ๋Ÿ‰๊ณจ์žฌ ์ฝ˜ํฌ๋ฆฌํŠธ์—์„œ ๋™์ผํ•˜๊ฒŒ 1.010์ด์—ˆ์œผ๋ฉฐ, ์—๋Ÿฌ๊ณ„์ˆ˜๋Š” ๊ฒฝ๋Ÿ‰๊ณจ์žฌ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ฒฝ์šฐ ๋ณดํ†ต์ค‘๋Ÿ‰ ์ฝ˜ํฌ๋ฆฌํŠธ๋ณด๋‹ค ๋” ๋‚ฎ์•˜๋‹ค. ์ด๋Š” ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰์„ ๊ณ ๋ คํ•จ์œผ๋กœ์จ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ํŒŒ๊ดด์ง„ํ–‰์˜์—ญ์—์„œ์˜ ๊ฒฝ๋Ÿ‰๊ณจ์žฌ์˜ ์˜ํ–ฅ์„ ์ž˜ ๊ณ ๋ คํ•˜์˜€๊ธฐ ๋•Œ๋ฌธ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค.

Table 1 Statistical comparisons of predictions by some models and test results

Type

Baลพant

Kim and Eo

This study

Prediction model

/Resources/kci/JKCI.2015.27.2.169/images/PICA5F4.gif

/Resources/kci/JKCI.2015.27.2.169/images/PICA633.gif

/Resources/kci/JKCI.2015.27.2.169/images/PICA809.gif

 Light

-weight aggregate

/Resources/kci/JKCI.2015.27.2.169/images/PICA868.gif

1.060

0.950

1.010

/Resources/kci/JKCI.2015.27.2.169/images/PICA8E6.gif

0.135

0.112

0.117

/Resources/kci/JKCI.2015.27.2.169/images/PICA935.gif

0.127

0.118

0.116

/Resources/kci/JKCI.2015.27.2.169/images/PICA9D2.gif

0.146

0.124

0.120

Normal

-weight aggregate

/Resources/kci/JKCI.2015.27.2.169/images/PICAC06.gif

1.050

1.010

1.010

/Resources/kci/JKCI.2015.27.2.169/images/PICAC65.gif

0.228

0.223

0.107

/Resources/kci/JKCI.2015.27.2.169/images/PICAC94.gif

0.217

0.220

0.106

/Resources/kci/JKCI.2015.27.2.169/images/PICACD4.gif

0.226

0.220

0.125

Note] /Resources/kci/JKCI.2015.27.2.169/images/PICAD33.gif,/Resources/kci/JKCI.2015.27.2.169/images/PICAD72.gif,/Resources/kci/JKCI.2015.27.2.169/images/PICADE1.gif, and /Resources/kci/JKCI.2015.27.2.169/images/PICAEAD.gif are the mean, standard deviation, coefficient of variation, and error coefficient, respectively.

/Resources/kci/JKCI.2015.27.2.169/images/PICBDE0.gif where /Resources/kci/JKCI.2015.27.2.169/images/PICBFF5.gif is the mean of the measured compressive strengths and /Resources/kci/JKCI.2015.27.2.169/images/PICC1EA.gif is the number of measured points.

/Resources/kci/JKCI.2015.27.2.169/images/PICC3DF.gif

Fig. 5 /Resources/kci/JKCI.2015.27.2.169/images/PICC42E.gif with lateral dimension of specimen

ํ•œํŽธ, ๊ตต์€๊ณจ์žฌ ์ตœ๋Œ€์น˜์ˆ˜์˜ ์˜ํ–ฅ์€ Kim and Eo์˜ ์—ฐ๊ตฌ์—์„œ ์ฒ˜๋Ÿผ ๊ทธ ์˜ํ–ฅ์„ ๋ฌด์‹œํ•˜๊ณ  ์œ ๋„ํ•œ ์‹ (14)๊ฐ€ ์‹คํ—˜๊ฒฐ๊ณผ๋ฅผ ๊ฐ€์žฅ ์ž˜ ์˜ˆ์ธกํ•˜๋Š” ๊ฒƒ์œผ๋กœ ๋‚˜์™”์œผ๋ฏ€๋กœ ์ด ์น˜์ˆ˜๊ฐ€ ์••์ถ•๊ฐ•๋„์— ๋ฏธ์น˜๋Š” ์˜ํ–ฅ์€ ๋งค์šฐ ์ ๋‹ค๊ณ  ํ•  ์ˆ˜ ์žˆ๋‹ค.

/Resources/kci/JKCI.2015.27.2.169/images/PICD6C3.gif

(a) Baลพant

/Resources/kci/JKCI.2015.27.2.169/images/PICD7DD.gif

(b) Kim and Eo

/Resources/kci/JKCI.2015.27.2.169/images/PICD965.gif

(c) This study

Fig. 6 /Resources/kci/JKCI.2015.27.2.169/images/PICD9E3.gif with main parameter (NWC: normal weight concrete, SLWC; sand light-weight concrete, ALWC; all light-weight concrete)

5. ๊ฒฐ    ๋ก 

์ด ์—ฐ๊ตฌ์—์„œ๋Š” ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰์„ ๊ณ ๋ คํ•œ ์••์ถ•๊ฐ•๋„์˜ ํฌ๊ธฐํšจ๊ณผ์— ๋Œ€ํ•œ ์˜ˆ์ธก๋ชจ๋ธ์˜ ๊ฐœ๋ฐœํ•˜๊ณ  ๊ธฐ์กด ์—ฐ๊ตฌ๊ฒฐ๊ณผ๋ฅผ ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šคํ™”ํ•˜์—ฌ ๋ช‡๋ช‡ ์—ฐ๊ตฌ์ž๋“ค์˜ ์—ฐ๊ตฌ๊ฒฐ๊ณผ์™€ ๋น„๊ตโ€ค๋ถ„์„ํ•œ ๊ฒฐ๊ณผ, ๋‹ค์Œ๊ณผ ๊ฐ™์€ ๊ฒฐ๋ก ์„ ์–ป์—ˆ๋‹ค.

1)ํ˜„์žฌ๊นŒ์ง€ ๋ฐœํ‘œ๋œ ํฌ๊ธฐํšจ๊ณผ๋ฒ•์น™์€ ๋ณดํ†ต์ค‘๋Ÿ‰ ์ฝ˜ํฌ๋ฆฌํŠธ์— ๊ธฐ๋ฐ˜ํ•˜๊ณ  ์žˆ์–ด ํŒŒ๊ดดํŠน์„ฑ์ด ๋‹ค๋ฅธ ๊ฒฝ๋Ÿ‰๊ณจ์žฌ ์ฝ˜ํฌ๋ฆฌํŠธ์—์„œ ๊ทธ ํ™œ์šฉ์„ฑ์ด ์˜๋ฌธ์‹œ๋˜๊ณ  ์žˆ๋‹ค.

2)์ด์— ์ด ์—ฐ๊ตฌ์—์„œ๋Š” ๋น„์„ ํ˜• ํŒŒ๊ดด์—ญํ•™์— ๊ธฐ๋ฐ˜ํ•œ Baลพant์™€ Kim and Eo์˜ ์˜ˆ์ธก๋ชจ๋ธ๋“ค์„ ๋ถ„์„ํ•˜๊ณ  ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰์„ ๊ณ ๋ คํ•œ ์••์ถ•๊ฐ•๋„์˜ ํฌ๊ธฐํšจ๊ณผ์— ๋Œ€ํ•œ ์˜ˆ์ธก๋ชจ๋ธ์„ ์ œ์‹œํ•˜์˜€๋‹ค.

3)๊ธฐ์กด์˜ ์—ฐ๊ตฌ๊ฒฐ๊ณผ๋“ค์„ ์ด์šฉํ•ด ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค๋ฅผ ๊ตฌ์ถ•ํ–ˆ์œผ๋ฉฐ ์ด์— ๋Œ€ํ•œ ๋น„์„ ํ˜• ํšŒ๊ท€๋ถ„์„์„ ํ†ตํ•ด ๊ธฐ์กด ์˜ˆ์ธก๋ชจ๋ธ๋“ค๊ณผ ์ œ์•ˆ๋œ ๋ชจ๋ธ์— ๋Œ€ํ•œ ์‹คํ—˜์ƒ์ˆ˜๋“ค์„ ๊ฒฐ์ •ํ–ˆ๋‹ค. ์ด๋กœ๋ถ€ํ„ฐ ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๊ธฐ๊ฑด๋‹จ์œ„์งˆ๋Ÿ‰์„ ๊ณ ๋ คํ•œ ๋ณธ ์—ฐ๊ตฌ์˜ ์˜ˆ์ธก๋ชจ๋ธ์ด Baลพant์™€ Kim and Eo์˜ ์˜ˆ์ธก๋ชจ๋ธ๋ณด๋‹ค ์‹คํ—˜๊ฒฐ๊ณผ๋ฅผ ์ž˜ ์˜ˆ์ธกํ•˜๊ณ  ์žˆ์Œ์„ ์•Œ ์ˆ˜ ์žˆ์—ˆ๋‹ค.

4)์ฝ˜ํฌ๋ฆฌํŠธ ์••์ถ•๊ฐ•๋„์˜ ํฌ๊ธฐํšจ๊ณผ์— ๋Œ€ํ•œ ํ†ต๊ณ„์  ๋ถ„์„๊ฒฐ๊ณผ ๋ณธ ์—ฐ๊ตฌ์˜ ์˜ˆ์ธก๋ชจ๋ธ์€ Baลพant์™€ Kim and Eo์˜ ์˜ˆ์ธก๋ชจ๋ธ๋ณด๋‹ค ๋ณ€๋™๊ณ„์ˆ˜์™€ ์—๋Ÿฌ๊ณ„์ˆ˜๊ฐ€ ๋” ์ž‘์•˜๋‹ค. ๋˜ํ•œ, ๋ณธ ์—ฐ๊ตฌ์˜ ์˜ˆ์ธก๋ชจ๋ธ์„ ํ†ตํ•ด ๊ฒฝ๋Ÿ‰๊ณจ์žฌ ์ฝ˜ํฌ๋ฆฌํŠธ์—์„œ ๊ตต์€๊ณจ์žฌ์˜ ์ตœ๋Œ€์น˜์ˆ˜๊ฐ€ ์••์ถ•๊ฐ•๋„์— ๋ฏธ์น˜๋Š” ์˜ํ–ฅ์€ ๋ฏธ๋ฏธํ•จ์„ ํ™•์ธํ–ˆ๋‹ค.

Acknowledgements

์ด ์—ฐ๊ตฌ๋Š” 2013๋…„๋„ ์ •๋ถ€(๋ฏธ๋ž˜์ฐฝ์กฐ๊ณผํ•™๋ถ€)์˜ ์žฌ์›์œผ๋กœ ํ•œ๊ตญ์—ฐ๊ตฌ์žฌ๋‹จ-๊ณต๊ณต๋ณต์ง€์•ˆ์ „์—ฐ๊ตฌ์‚ฌ์—…(No. 2013067519)์˜ ์ง€์›์„ ๋ฐ›์•„ ์ˆ˜ํ–‰๋˜์—ˆ๊ณ , ์ด์— ๊ฐ์‚ฌ๋“œ๋ฆฝ๋‹ˆ๋‹ค.

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