Mobile QR Code QR CODE : Journal of the Korean Society of Civil Engineers

  1. ์ •ํšŒ์›โ€ค๊ฒฝ๋‚จ๋Œ€ํ•™๊ต ์‚ฌํšŒ๊ธฐ๋ฐ˜์‹œ์Šคํ…œ๊ณตํ•™๊ณผ ์„์‚ฌ๊ณผ์ • (Kyungnam Universityโ€คqkrwlstn966@naver.com)
  2. ์ •ํšŒ์›โ€ค๊ต์‹ ์ €์žโ€ค๊ฒฝ๋‚จ๋Œ€ํ•™๊ต ๊ฑด์„ค์‹œ์Šคํ…œ๊ณตํ•™๊ณผ ๊ต์ˆ˜, ๊ณตํ•™๋ฐ•์‚ฌ (Corresponding Authorโ€คKyungnam Universityโ€คbhkim@kyungnam.ac.kr)



์ž์†ํˆฌ๊ณผ์œจ, ํ”„๋ฆฌ์ŠคํŠธ๋ ˆ์Šค ์ฝ˜ํฌ๋ฆฌํŠธ, ์ŠคํŠธ๋žœ๋“œ, ๊ธด์žฅ์‘๋ ฅ
Permeability of magnetic flux, Prestressed concrete, Strand, Prestress

1. ์„œ ๋ก 

PSC (Prestressed Concrete) ๊ตฌ์กฐ๊ณ„๋Š” ๊ณ ๊ฐ•๋„ ๊ธด์žฅ์žฌ๋ฅผ ์ด์šฉํ•˜์—ฌ ๋ฏธ๋ฆฌ ์ธ์žฅ์‘๋ ฅ์„ ์ฃผ์–ด์„œ ์ฒ ๊ทผ์ฝ˜ํฌ๋ฆฌํŠธ์˜ ๋‹จ์ ์ธ ์ธ์žฅ๊ท ์—ด์„ ํ”ผํ•˜๋Š” ์‹œ์Šคํ…œ์ด๋‹ค. PSC ๊ตฌ์กฐ๊ณ„์˜ ๊ธด์žฅ์žฌ๋Š” ์ƒ์‹œ ๋†’์€ ์‘๋ ฅ ์ƒํƒœ๋ฅผ ์œ ์ง€ํ•˜๊ณ  ์žˆ๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ ๊ธด์žฅ์žฌ๋Š” ์ฆ‰์‹œ ์†์‹ค๋ฟ๋งŒ ์•„๋‹ˆ๋ผ, ํฌ๋ฆฌํ”„ ๋ฐ ๊ฑด์กฐ์ˆ˜์ถ• ๋“ฑ์˜ ์‹œ๊ฐ„์  ์†์‹ค๋กœ ์ธํ•ด์„œ ์ง€์†์ ์œผ๋กœ ๊ฐ์†Œํ•˜๊ณ  ์žˆ๋‹ค. ๊ธด์žฅ์žฌ์˜ ๊ธด์žฅ์‘๋ ฅ ์†์‹ค์€ PSC ๊ตฌ์กฐ๊ณ„ ์ „์ฒด ์‹œ์Šคํ…œ์˜ ์•ˆ์ „ ๋ฌธ์ œ๋ฅผ ์•ผ๊ธฐํ•  ์ˆ˜ ์žˆ๋‹ค. ๊ทธ๋Ÿฌ๋ฏ€๋กœ ๊ธด์žฅ์žฌ์˜ ๊ธด์žฅ์‘๋ ฅ์„ ์ฃผ๊ธฐ์ ์œผ๋กœ ๋ชจ๋‹ˆํ„ฐ๋ง ํ•˜๋Š” ๊ฒƒ์€ ๋งค์šฐ ์ค‘์š”ํ•˜๋‹ค.

๊ธด์žฅ์žฌ์˜ ๊ธด์žฅ์‘๋ ฅ์„ ์ถ”์ •ํ•˜๊ธฐ ์œ„ํ•œ ๋‹ค์–‘ํ•œ ๋น„ํŒŒ๊ดด ๊ฒ€์‚ฌ ๊ธฐ์ˆ ๋“ค์ด ์—ฐ๊ตฌ๋˜์—ˆ๋Š”๋ฐ(Hiba and Branko, 2019), ์ง„๋™ ๊ธฐ๋ฒ•(Kim and Park, 2007), ์Œํ–ฅ๋ฐฉ์ถœ ๊ธฐ๋ฒ•(Kim et al., 2019a), ์œ ๋„์ดˆ์ŒํŒŒ ๊ธฐ๋ฒ•, EM ๊ธฐ๋ฒ•(Kim et al., 2015a), EMI ๊ธฐ๋ฒ•(Park et al., 2010), ๋ณ€ํ˜•๋ฅ  ๊ธฐ๋ฒ•(Kim et al., 2015b), ์ „์ž๊ธฐ ์ง„๋™๋ฒ•(Li et al., 2018) ๊ทธ๋ฆฌ๊ณ  ์ž์†ํˆฌ๊ณผ์œจ ๊ธฐ๋ฒ•(Kim et al., 2013) ๋“ฑ์ด ์ฃผ๋ชฉ๋œ๋‹ค.

์ง„๋™ ๊ธฐ๋ฒ•์€ ์ผ€์ด๋ธ”์˜ ๊ณ ์œ ์ง„๋™์ˆ˜๋ฅผ ์ด์šฉํ•˜์—ฌ ์ผ€์ด๋ธ” ์žฅ๋ ฅ์„ ์ถ”์ •ํ•˜๋Š” ๋ฐฉ๋ฒ•์ด๋‹ค. ํ˜„์žฅ์ ์šฉ์„ ํ†ตํ•ด ์ง„๋™ ๊ธฐ๋ฒ•์„ ์ด์šฉํ•œ ์ผ€์ด๋ธ” ์žฅ๋ ฅ ์ถ”์ •์€ ํ˜„์žฌ๊นŒ์ง€ ์‹ค๋ฌด์— ์ ์šฉ๋˜๊ณ  ์žˆ๋‹ค. ์ตœ๊ทผ์—๋Š” ์ผ€์ด๋ธ” ์žฅ๋ ฅ ์ถ”์ •์„ ์œ„ํ•ด ์ธ๊ณต์‹ ๊ฒฝ๋ง ๋ชจ๋ธ์„ ๊ฐœ๋ฐœํ•˜์˜€๋‹ค(Kim et al., 2020). ๊ทธ๋Ÿฌ๋‚˜ ์ง„๋™ ๊ธฐ๋ฒ•์€ ์‚ฌ์žฅ๊ต ์ผ€์ด๋ธ”, ํ˜„์ˆ˜๊ต ํ–‰์–ด ๋ฐ ๋น„๋ถ€์ฐฉ PSC์˜ ๊ธด์žฅ์žฌ ์žฅ๋ ฅ ์ถ”์ •์— ์ ์šฉ์ด ๊ฐ€๋Šฅํ•˜๋‚˜, ๋ถ€์ฐฉ์‹ PSC ๊ธด์žฅ์žฌ์˜ ์žฅ๋ ฅ ์ถ”์ •์—๋Š” ์ ์šฉ์ด ์–ด๋ ต๋‹ค.

์Œํ–ฅ๋ฐฉ์ถœ ๊ธฐ๋ฒ•์€ ๊ธด์žฅ์žฌ์˜ ํŒŒ๋‹จ์— ์˜ํ•ด ๋ฐœ์ƒ๋˜๋Š” ํƒ„์„ฑํŒŒ๋ฅผ ํƒ์ง€ํ•˜์—ฌ PSC๊ตฌ์กฐ๋ฌผ์˜ ํŒŒ๋‹จ ๋ฐœ์ƒ ์—ฌ๋ถ€๋ฅผ ๊ฐ์‹œํ•˜๋Š” ์ƒ์‹œ ๋ชจ๋‹ˆํ„ฐ๋ง ๊ธฐ๋ฒ•์ด๋‹ค. ์Œํ–ฅ๋ฐฉ์ถœ ๊ธฐ๋ฒ•์€ PSC ๊ตฌ์กฐ๋ฌผ ๋‚ด๋ถ€ ํ…๋˜์˜ ํŒŒ๊ดด๊ฑฐ๋™(Kim et al., 2019b) ๋ฐ PSC ๊ฑฐ๋”๊ต ์•ˆ์ „์ง„๋‹จ ์—ฐ๊ตฌ(Kim et al., 2021) ๋“ฑ์— ์ ์šฉ๋˜์—ˆ๋‹ค.

EM (Elasto-Magnetic)๊ธฐ๋ฒ•์€ EM ์„ผ์„œ๋ฅผ ํ†ตํ•˜์—ฌ ์ž๊ธฐํˆฌ์ž์œจ์„ ์ธก์ •ํ•˜๊ณ  ์žฅ๋ ฅ์„ ์ถ”์ •ํ•œ๋‹ค. Jeon et al.(2019)์€ FCM (Free Cantilever Method) ๊ฐ€์„ค ๊ฐ•๋ด‰์˜ ๊ธด์žฅ๋ ฅ ์ถ”์ •์— EM ๊ธฐ๋ฒ•์„ ์ ์šฉํ•˜์˜€๊ณ , Chen et al.(2018)์€ PSC ํ…๋˜์ด ์˜จ๋„๋ณ€ํ™”์— ๋”ฐ๋ฅธ ๊ธด์žฅ๋ ฅ์˜ ์žฅ๊ธฐ์†์‹ค์— ๋Œ€ํ•œ ์—ฐ๊ตฌ๋ฅผ ์ˆ˜ํ–‰ํ•˜์˜€๋‹ค. Park et al.(2019)์€ PSC ๋‚ด๋ถ€ ํ…๋˜์˜ ๊ธด์žฅ๋ ฅ ํ‰๊ฐ€๋ฅผ ์œ„ํ•œ ์ €์ „์•• EM์„ผ์‹ฑ ๊ธฐ๋ฒ•์„ ๊ฒ€์ฆํ•˜์˜€๋‹ค.

EMI (Electro Magnetic Interference)๊ธฐ๋ฒ•์€ PZT (Piezoelectricity) ์••์ „ ์žฌ๋ฃŒ๋ฅผ ์ด์šฉํ•˜์—ฌ ์ „๊ธฐ์  ์ž„ํ”ผ๋˜์Šค(Electrical Impedance)๋ฅผ ์ธก์ •ํ•˜๊ณ  ์žฅ๋ ฅ์„ ์ถ”์ •ํ•œ๋‹ค. ๊ตฌ์กฐ๋ฌผ์˜ ํ‘œ๋ฉด์— ์••์ „ ์„ผ์„œ๋ฅผ ๋ถ€์ฐฉํ•˜๊ณ  ๊ณ ์ฃผํŒŒ ์ž„ํ”ผ๋˜์Šค๋ฅผ ์ด์šฉํ•˜์—ฌ ์žฅ๋ ฅ์„ ์ถ”์ •ํ•œ๋‹ค(Dang et al., 2019; Na and Baek, 2018; Ryu et al., 2019; Zhu and Scalea, 2016).

๋ณ€ํ˜•๋ฅ  ๊ธฐ๋ฒ•์€ ๊ด‘์„ฌ์œ  ์„ผ์„œ๋ฅผ ์ด์šฉํ•˜์—ฌ ๋ณ€์œ„๋ฅผ ๊ณ„์ธกํ•˜๊ณ  ์žฅ๋ ฅ์„ ์ถ”์ •ํ•œ๋‹ค. ๊ธฐ์กด ๊ฐ•์—ฐ์„ ์˜ ์ค‘์‹ฌ ๊ฐ•์„ ์„ ๊ฐ•์žฌ ํŠœ๋ธŒ๋กœ ๋Œ€์ฒดํ•˜๊ณ , FRP๊ด‘์„ฌ์œ  ์„ผ์„œ๋ฅผ ์„ค์น˜ํ•˜์—ฌ ๊ฐ•์—ฐ์„ ์˜ ๋ณ€ํ˜•๋ฅ ์„ ์ธก์ •ํ•œ๋‹ค(Shen et al., 2018).

์ „์ž๊ธฐ ์ง„๋™๋ฒ•์€ ๊ฐ•์—ฐ์„ ์„ ์ธ๋•ํ„ด์Šค(Inductance)์™€ ์ปคํŒจ์‹œํ„ด์Šค(Capacitance)๋กœ ๋ชจ๋ธ๋งํ•˜์—ฌ ๊ฐ•์—ฐ์„ ์˜ ๊ธด์žฅ์‘๋ ฅ์„ ์ถ”์ •ํ•œ๋‹ค(Chen et al., 2018). ๊ธด์žฅ์‘๋ ฅ๊ณผ ์ฃผํŒŒ์ˆ˜์˜ ์‚ฌ์ด๊ฐ€ ์„ ํ˜•๊ด€๊ณ„์ž„์„ ๋ฐํ˜€๋‚ด์—ˆ์ง€๋งŒ, ๊ฐ•์—ฐ์„ ์˜ ๊ธธ์ด์— ๋”ฐ๋ผ์„œ๋„ ๋ณ€ํ™˜๋˜๋Š” ๋ฌธ์ œ์ ์ด ์žˆ๋‹ค(Zhang et al., 2019). ์ตœ๊ทผ์—๋Š” ๊ฐ•์„ ์˜ ์ €์ฃผํŒŒ ์ž„ํ”ผ๋˜์Šค๋ฅผ ๊ณ„์ธกํ•˜์—ฌ ๊ธด์žฅ์‘๋ ฅ์„ ์ถ”์ •ํ•  ์ˆ˜ ์žˆ๋Š” ๋ฐฉ๋ฒ•์ด ์ œ์•ˆ๋˜์—ˆ๋‹ค(Nguyen and Kim, 2020).

์ž์†ํˆฌ๊ณผ์œจ ๊ธฐ๋ฒ•์€ ๊ธด์žฅ์žฌ ๋‚ด๋ถ€์˜ ์ž์†ํˆฌ๊ณผ์œจ์„ ์ธก์ •ํ•˜์—ฌ ๊ธด์žฅ๋ฅ ์„ ์ถ”์ •ํ•œ๋‹ค. PS ๊ฐ•์„ ์˜ ์ž์†ํˆฌ๊ณผ์œจ์„ ์ธก์ •ํ•˜๊ธฐ ์œ„ํ•ด์„œ ํ์ž๊ธฐ ํšŒ๋กœ(Magnetic Closed Loop Circuit)๊ฐ€ ๊ตฌ์„ฑ๋˜์—ˆ๊ณ , ๊ธด์žฅ๋ฅ ๊ณผ ์ž์†ํˆฌ๊ณผ์œจ์€ ์„ ํ˜• ๋น„๋ก€ํ•œ๋‹ค๋Š” ๊ฒฐ๊ณผ๋ฅผ ๋„์ถœํ•˜์˜€๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ PS ๊ฐ•์„ ์— ๋Œ€ํ•œ ํ์ž๊ธฐ ํšŒ๋กœ ๊ตฌ์„ฑ์ด ์–ด๋ ต๊ณ , ์ผ์ • ์„ธ๊ธฐ ์ด์ƒ์˜ ์ž๊ธฐ์žฅ์ด ํ๋ฅด๋Š” ๊ฒฝ์šฐ์—๋งŒ ์‘๋‹ต์˜ ์‹ ๋ขฐ์„ฑ์ด ํ™•๋ณด๋˜๋Š” ๋ฌธ์ œ์ ์ด ๋ณด๊ณ ๋˜์—ˆ๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ ๊ธด์žฅ๋ฅ  ์ด์™ธ์— ์˜จ๋„ ๋ฐ ์„ผ์„œ ๊ฐ„๊ฒฉ ๊ฐ™์€ ์ฃผ์š” ์˜ํ–ฅ ์ธ์ž๋“ค์— ๋Œ€ํ•œ ์ž์†ํˆฌ๊ณผ์œจ์˜ ๋ฏผ๊ฐ๋„๋Š” ๋ณด๊ณ ๋˜์ง€ ๋ชปํ•˜์˜€๋‹ค. ํŠนํžˆ, ๊ธด์žฅ๋ฅ ์˜ ์˜จ๋„์— ๋Œ€ํ•œ ํฐ ๋ฏผ๊ฐ๋„๋Š” ๋‹ค์ˆ˜์˜ ์—ฐ๊ตฌ(Kim et al., 2015c; Nguyen and Kim, 2020)์—์„œ ๋ณด๊ณ ๋œ ๋ฐ” ์žˆ๋‹ค.

๋ณธ ๋…ผ๋ฌธ์€ ๊ธฐ์กด์˜ ์ž์†ํˆฌ๊ณผ์œจ ๊ธฐ๋ฒ•์ด ๊ฐ€์ง€๊ณ  ์žˆ๋Š” ๋ฌธ์ œ์ ์„ ๊ฐœ์„ ํ•˜๊ธฐ ์œ„ํ•œ ์ตœ์ดˆ ์‹œ๋„๋กœ์„œ, ํ์ž๊ธฐ ํšŒ๋กœ ๋Œ€์‹ ์— ๊ฐœ์ž๋กœ ํšŒ๋กœ(Magnetic Open Loop Circuit)๋ฅผ ์ด์šฉํ•˜๋Š” ๋ฐฉ๋ฒ•์„ ์œ„ํ•œ ๊ธฐ์ดˆ์—ฐ๊ตฌ๋กœ์„œ ์ž์†ํˆฌ๊ณผ์œจ, ์˜จ๋„ ๋ฐ ๊ธด์žฅ๋ฅ  ์‚ฌ์ด์˜ ์‹คํ—˜์  ๊ด€๊ณ„๋ฅผ ๊ทœ๋ช…ํ•œ๋‹ค. PS ๊ธด์žฅ์žฌ์˜ ์ž์†ํˆฌ๊ณผ์œจ-์˜จ๋„-๊ธด์žฅ๋ฅ  ์‚ฌ์˜์˜ ์‹คํ—˜์  ์ƒํ˜ธ๊ด€๊ณ„๋ฅผ ๋ฏธ๋ฆฌ ์•Œ๊ณ  ์žˆ๋‹ค๋ฉด, ํ˜„์žฅ์—์„œ๋Š” PS ๊ฐ•์žฌ์˜ ์ž์†ํˆฌ๊ณผ์œจ๊ณผ ์˜จ๋„๋งŒ์„ ๊ณ„์ธกํ•จ์œผ๋กœ์จ, PS ๊ธด์žฅ์žฌ์˜ ํ˜„์žฌ ๊ธด์žฅ์‘๋ ฅ ์ˆ˜์ค€์„ ํ‰๊ฐ€ํ•  ์ˆ˜ ์žˆ๋‹ค.

2. ์ž์†ํˆฌ๊ณผ์œจ ์‹คํ—˜์˜ ์„ค์ •

2.1 ์ž์†ํˆฌ๊ณผ์œจ์„ ์ด์šฉํ•œ ๊ธด์žฅ๋ฅ  ๊ณ„์ธก์›๋ฆฌ

์†”๋ ˆ๋…ธ์ด๋“œ(Solenoid)๋Š” ์ฝ”์ผ(Coil)์ด ์›ํ†ตํ˜• ๋ชจ์–‘์œผ๋กœ ์ด˜์ด˜ํžˆ ๊ท ์ผ ๊ฐ„๊ฒฉ์œผ๋กœ ์—ฌ๋Ÿฌ ๋ฒˆ ๊ฐ๊ธด ๊ธฐ๊ตฌ์ด๋‹ค. ์†”๋ ˆ๋…ธ์ด๋“œ์— ์ „๋ฅ˜๋ฅผ ์ธ๊ฐ€ํ•˜๋ฉด, ์•™ํŽ˜๋ฅด์˜ ์˜ค๋ฅธ๋‚˜์‚ฌ ๋ฒ•์น™(Ampereโ€™s Right-Handed Screw Rule)์œผ๋กœ ์ธํ•˜์—ฌ ์†”๋ ˆ๋…ธ์ด๋“œ ๋‚ด๋ถ€์— ์ž์†(Magnetic Flux)์ด ํ๋ฅด๊ฒŒ ๋œ๋‹ค. ์ด๋•Œ, ์ž์†๋ฐ€๋„(Magnetic Flux Density)๋Š” ๋‹ค์Œ Eq. (1)๊ณผ ๊ฐ™์ด ์ „๋ฅ˜์˜ ์„ธ๊ธฐ์™€ ๋‹จ์œ„๊ธธ์ด ๋‹น ๋„์„ ์˜ ๊ฐ๊ธด ์ˆ˜์— ๋น„๋ก€ํ•œ๋‹ค.

(1)
$B=\mu_{o}\dfrac{N I}{L}$

์—ฌ๊ธฐ์„œ, $B(T=Wb/m^{2})$๋Š” ์ž์†๋ฐ€๋„(Magnetic Flux Density), N์€ ์†”๋ ˆ๋…ธ์ด๋“œ์˜ ๊ฐ์€ ํšŸ์ˆ˜, I(A)๋Š” ์ „๋ฅ˜, L(m)์€ ์†”๋ ˆ๋…ธ์ด๋“œ์˜ ๊ธธ์ด, ๊ทธ๋ฆฌ๊ณ  $\mu_{o}$๋Š” ์†”๋ ˆ๋…ธ์ด๋“œ ๋‚ด๋ถ€๊ฐ€ ์ง„๊ณต์ƒํƒœ ์‹œ ํˆฌ์ž์œจ์„ ๋‚˜ํƒ€๋‚ธ๋‹ค. ์†”๋ ˆ๋…ธ์ด๋“œ ๋‚ด๋ถ€์— ๊ธด์žฅ์žฌ์™€ ๊ฐ™์€ ์ž์„ฑ์ฒด๊ฐ€ ์กด์žฌํ•œ๋‹ค๋ฉด, ๊ธด์žฅ์žฌ๋Š” ์ž๊ธฐ์œ ๋„(Magnetic Induction)๋˜๋ฉฐ, ์ž๊ธฐ์œ ๋„๋œ ๊ธด์žฅ์žฌ๋Š” ์žํ™”๋œ๋‹ค. ์ด๋•Œ, ๊ธด์žฅ์žฌ์˜ ์ž์†๋ฐ€๋„๋Š” ๋‹ค์Œ Eq. (2)์™€ ๊ฐ™๋‹ค.

(2)
$B=\mu\dfrac{N I}{L}=\mu_{o}\mu_{r}\dfrac{N I}{L}$

์—ฌ๊ธฐ์„œ, $\mu$($H/m$)๋Š” ์ „์ฒด ํˆฌ์ž์œจ์ด๋ฉฐ, $\mu_{r}$์€ ์ƒ๋Œ€ ํˆฌ์ž์œจ๋กœ์„œ ๋ฌด ์ฐจ์›์ด๋‹ค.

์†”๋ ˆ๋…ธ์ด๋“œ๋ฅผ ์ด์šฉํ•˜์—ฌ ์ž์†ํˆฌ๊ณผ์œจ์„ ๊ณ„์ธกํ•˜๋Š” ์›๋ฆฌ๊ฐ€ Fig. 1์— ๋ณด์ธ๋‹ค. ๊ฐ€์ง„์†”๋ ˆ๋…ธ์ด๋“œ์— ์ „๋ฅ˜๋ฅผ ์ธ๊ฐ€ํ•˜๋ฉด, ๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ No.1๋ฒˆ๊ณผ No.2๋ฒˆ ๋‚ด๋ถ€์— ์ž์†์ด ํ๋ฅธ๋‹ค. ์ž์†์ด ํ๋ฅด๋ฉด ๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ No.1, No.2์— ์ „์ž๊ธฐ ์œ ๋„ํ˜„์ƒ์œผ๋กœ ์ธํ•˜์—ฌ ์œ ๋„๊ธฐ์ „๋ ฅ(Induced Electromotive Force), $V_{1,\:}V_{2}$, ์ด ๋ฐœ์ƒํ•œ๋‹ค. ๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ์— ์ธก์ •๋œ ์œ ๋„๊ธฐ์ „๋ ฅ์€ ๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ์— ๊ฐ๊ธด ์ฝ”์ผ์˜ ์ˆ˜, N, ์™€ ์ž์†์˜ ๋ณ€ํ™”์œจ์— ๋น„๋ก€ํ•œ๋‹ค. ์ด๋ฅผ ํŽ˜๋Ÿฌ๋ฐ์ด ๋ฒ•์น™(Faraday's Law)์ด๋ผ๊ณ  ํ•˜๋ฉฐ(Griffiths, 2019), ๋‹ค์Œ Eq. (3)๊ณผ ๊ฐ™๋‹ค.

Fig. 1. Measuring Principle of Permeability of Magnetic Flux
../../Resources/KSCE/Ksce.2022.42.3.0323/fig1.png
(3)
$V=-N\dfrac{d\phi}{dt}$

๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ์— ๊ณ„์ธก๋œ ์œ ๋„๊ธฐ์ „๋ ฅ์„ ์ˆ˜์น˜ ์ ๋ถ„ํ•˜๋ฉด, ๊ธด์žฅ์žฌ์— ํ๋ฅด๋Š” ์ž์†์„ ๋‹ค์Œ Eq. (4)์™€ ๊ฐ™์ด ์‚ฐ์ •ํ•  ์ˆ˜ ์žˆ๋‹ค.

(4)
$\phi =-\dfrac{1}{N}Vdt$

๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ No.1์—์„œ ์‚ฐ์ •๋œ ์ž์†์„ $\phi_{1}$์ด๋ผ ํ•˜๊ณ , ๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ No.1์œผ๋กœ ๋ถ€ํ„ฐ ๊ฐ„๊ฒฉ $s$๋งŒํผ ๋–จ์–ด์ง„ ๊ณณ์— ์œ„์น˜ํ•œ ๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ No.2์—์„œ ์‚ฐ์ •๋œ ์ž์†์„ $\phi_{2}$๋ผ ํ•˜์ž. Eq. (5)์™€ ๊ฐ™์ด ๋‘ ์ง€์  ์‚ฌ์ด์˜ ์ž์†์ด ํ†ต๊ณผํ•˜๋Š” ๋ฐฑ๋ถ„์œจ์„ ์ž์†ํˆฌ๊ณผ์œจ(Permeability of Magnetic Flux), $p$,๋กœ ์ •์˜ํ•œ๋‹ค.

(5)
$p=\dfrac{(\phi_{1}-\phi_{2})}{\phi_{1}}\times 100$

๋˜ํ•œ, Eq. (6)๊ณผ ๊ฐ™์ด ๊ธด์žฅ์žฌ์˜ ์ธ์žฅ๊ฐ•๋„ ๋Œ€๋น„ ๋„์ž…๋œ ๊ธด์žฅ์‘๋ ฅ์˜ ์ˆ˜์ค€์„ ๊ธด์žฅ๋ฅ (Prestressing Ratio), $r$,๋กœ ์ •์˜ํ•œ๋‹ค.

(6)
$r=\dfrac{f}f_{u}\times 100$

์—ฌ๊ธฐ์„œ, $f$์€ ๋„์ž…๋œ ๊ธด์žฅ์‘๋ ฅ์ด๋ฉฐ, $f_{u}$๋Š” ๊ธด์žฅ์žฌ์˜ ์ธ์žฅ๊ฐ•๋„๋ฅผ ๋‚˜ํƒ€๋‚ธ๋‹ค.

2.2 ์‹คํ—˜๊ฐœ์š”

Fig. 2๋Š” ์‹คํ—˜ ๊ฐœ์š”๋„๋ฅผ ๋ณด์—ฌ์ค€๋‹ค. ๊ธด์žฅ์žฌ๋Š” ๋งŒ๋Šฅ์žฌ๋ฃŒ์‹œํ—˜๊ธฐ(Universal Testing Machine)์— ์ง€๊ทธ(Jig)๋ฅผ ์ด์šฉํ•˜์—ฌ ์๊ธฐ๋ฐฉ์‹์œผ๋กœ ์ •์ฐฉ๋˜์—ˆ๋‹ค. ์†”๋ ˆ๋…ธ์ด๋“œ ํŒŒ์ดํ”„(Solenoid Pipe)๋Š” ๊ธด์žฅ์žฌ์˜ ์ž์†ํˆฌ๊ณผ์œจ์„ ์ธก์ •ํ•˜๊ธฐ ์œ„ํ•˜์—ฌ ๊ธด์žฅ์žฌ ๋‘˜๋ ˆ์— ์žฅ์ฐฉ๋˜์—ˆ๋‹ค. ์ž์ฒด ์ œ์ž‘๋œ ํ•ญ์˜จ๊ธฐ(Temperature Chamber)๊ฐ€ ๊ธด์žฅ์žฌ ์˜จ๋„๋ฅผ ์ œ์–ดํ•˜๊ธฐ ์œ„ํ•˜์—ฌ ๋งŒ๋Šฅ์žฌ๋ฃŒ์‹œํ—˜๊ธฐ์— ์„ค์น˜๋˜์—ˆ๋‹ค. RTD (Resistance Thermometer)๋Š” ํ•ญ์˜จ๊ธฐ ๋‚ด๋ถ€์˜ ๊ธด์žฅ์žฌ ์˜จ๋„๋ฅผ ๊ณ„์ธกํ•˜๊ธฐ ์œ„ํ•˜์—ฌ ์„ค์น˜๋˜์—ˆ๋‹ค. ์ „์›๊ณต๊ธ‰์žฅ์น˜(Power Supply)๋Š” ๊ฐ€์ง„์†”๋ ˆ๋…ธ์ด๋“œ์— ๊ต๋ฅ˜์ „์›์„ ๊ณต๊ธ‰ํ•œ๋‹ค. ๊ฐ€์ง„์†”๋ ˆ๋…ธ์ด๋“œ์— ๊ณต๊ธ‰๋œ ๊ต๋ฅ˜์ „์›์€ ๊ธด์žฅ์žฌ์— ์ž์†์„ ํ๋ฅด๊ฒŒ ํ•œ๋‹ค. ๊ต๋ฅ˜๋กœ ์ธํ•˜์—ฌ ๋ณ€๋™๋˜๋Š” ์ž์†์€ ๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ์— ์œ ๋„๊ธฐ์ „๋ ฅ์„ ๋ฐœ์ƒ์‹œํ‚ค๊ณ , ๋ฐ์ดํ„ฐ๋กœ๊ฑฐ(Data Logger)๋ฅผ ํ†ตํ•˜์—ฌ ์ƒ˜ํ”Œ๋ง๋œ ์ „์••์ด ๋…ธํŠธ๋ถ์— ๊ธฐ๋ก๋˜์—ˆ๋‹ค.

Fig. 2. Test Setup
../../Resources/KSCE/Ksce.2022.42.3.0323/fig2.png

๊ธด์žฅ์žฌ์— ๊ธด์žฅ์‘๋ ฅ์„ ๋„์ž…ํ•˜๊ธฐ ์œ„ํ•ด์„œ ์‚ฌ์šฉ๋œ ๋งŒ๋Šฅ์žฌ๋ฃŒ์‹œํ—˜๊ธฐ๋Š” Instron์‚ฌ์˜ ๋ชจ๋ธ 4485 (Instron, 2012)๊ธฐ์ข…์ด๋‹ค. ๊ธด์žฅ์žฌ์— ๊ธด์žฅ์‘๋ ฅ์€ ์ธ์žฅ์‹œํ—˜๊ธฐ์˜ ์ˆ˜๋™์ปจํŠธ๋กค๋Ÿฌ๋ฅผ ์ง์ ‘ ์กฐ์ž‘ํ•˜์—ฌ ๋„์ž…๋˜์—ˆ๋‹ค.

Fig. 3์€ ๋ณธ ์‹คํ—˜์„ ์œ„ํ•˜์—ฌ ํŠน์ˆ˜ ์ œ์ž‘๋œ ์ง€๊ทธ๋ฅผ ๋ณด์—ฌ์ค€๋‹ค. ์ง€๊ทธ๋Š” ๊ธด์žฅ์žฌ๊ฐ€ ์ธ์žฅ๊ธฐ์— ํ™•๊ณ ํžˆ ์ •์ฐฉ๋  ์ˆ˜ ์žˆ๋„๋ก ๋„์™€์ฃผ๋Š” ๊ธฐ๊ตฌ์ด๋‹ค. ์ง€๊ทธ๋Š” ๊ฐ•์žฌ SS400์˜ ์žฌ๋ฃŒ๋ฅผ ์‚ฌ์šฉํ•˜์—ฌ ์ œ์ž‘๋˜์—ˆ๋‹ค.

Figs. 4 and 5๋Š” ๊ฐ๊ฐ ๊ธด์žฅ์žฌ์˜ ์ž์†ํˆฌ๊ณผ์œจ์„ ์ธก์ •ํ•˜๊ธฐ ์œ„ํ•œ ์†”๋ ˆ๋…ธ์ด๋“œ ํŒŒ์ดํ”„์™€ ์ œ์›์„ ๋ณด์—ฌ์ค€๋‹ค. ์†”๋ ˆ๋…ธ์ด๋“œ ํŒŒ์ดํ”„๋Š” 3D CAD๋ฅผ ์ด์šฉํ•˜์—ฌ ์ž์ฒด ์„ค๊ณ„๋˜์—ˆ๊ณ , 3D ํ”„๋ฆฐํ„ฐ๋ฅผ ์‚ฌ์šฉํ•˜์—ฌ PLA+ ํ•„๋ผ๋ฉ˜ํŠธ ์žฌ์งˆ๋กœ ์ œ์ž‘๋˜์—ˆ๋‹ค. ์†”๋ ˆ๋…ธ์ด๋“œ ํŒŒ์ดํ”„์˜ ๋‚ด๊ฒฝ์€ ๊ธด์žฅ์žฌ์˜ ์™ธ๊ฒฝ๋ณด๋‹ค ์กฐ๊ธˆ ์ปค์„œ ๊ธด์žฅ์žฌ์™€ ์†”๋ ˆ๋…ธ์ด๋“œ ํŒŒ์ดํ”„๋Š” ์•ฝ๊ฐ„์˜ ๊ฐญ(Gap)์„ ๊ฐ€์ง€๊ณ  ์„œ๋กœ ์ด๊ฒฉ ๋˜์–ด์žˆ๋‹ค. ๋”ฐ๋ผ์„œ ๊ธด์žฅ์žฌ๊ฐ€ ์ธ์žฅ์ด ๋˜์–ด ๋Š˜์–ด๋‚˜๋„ ์†”๋ ˆ๋…ธ์ด๋“œ ํŒŒ์ดํ”„์˜ ์†”๋ ˆ๋…ธ์ด๋“œ ๊ฐ„๊ฒฉ์ด ์ผ์ •ํ•˜๊ฒŒ ์œ ์ง€๋œ๋‹ค.

Fig. 3. Jigs for PS Steel
../../Resources/KSCE/Ksce.2022.42.3.0323/fig3.png
Fig. 4. Solenoid Pipe for PS Wire (unit: mm)
../../Resources/KSCE/Ksce.2022.42.3.0323/fig4.png
Fig. 5. Solenoid Pipe for PS Strand (unit: mm)
../../Resources/KSCE/Ksce.2022.42.3.0323/fig5.png

Table 1์€ ์†”๋ ˆ๋…ธ์ด๋“œ ํŒŒ์ดํ”„์˜ ์ œ์›์„ ๋ณด์—ฌ์ค€๋‹ค. ์†”๋ ˆ๋…ธ์ด๋“œ ํŒŒ์ดํ”„๋Š” ํ•œ ๊ฐœ์˜ ๊ฐ€์ง„์†”๋ ˆ๋…ธ์ด๋“œ์™€ ๋‘ ๊ฐœ์˜ ๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ๋กœ ๊ตฌ์„ฑ๋˜์—ˆ๋‹ค. ์†”๋ ˆ๋…ธ์ด๋“œ์˜ ๊ตฌ์„ฑ์—๋Š” ์—๋‚˜๋ฉœ์„ ์ด ์‚ฌ์šฉ๋˜์—ˆ๋‹ค. ์—๋‚˜๋ฉœ์„ ์˜ ์ง๊ฒฝ์€ 0.3 mm์ด๊ณ , ์†”๋ ˆ๋…ธ์ด๋“œ์˜ ํญ๊ณผ ๊ฐ„๊ฒฉ์€ ๊ฐ๊ฐ 10 mm๊ณผ 5 mm์ด๋‹ค.

Table 1. Specification of Solenoid Pipe

PS Wire

PS Strand

Inner Diameter (mm)

8

16

Outer Diameter (mm)

10

18

Number of Turns (N)

200

200

Fig. 6์€ ๋งŒ๋Šฅ์žฌ๋ฃŒ์‹œํ—˜๊ธฐ์— ์„ค์น˜๋œ ํ•ญ์˜จ๊ธฐ๋ฅผ ๋ณด์—ฌ์ค€๋‹ค. ํ•ญ์˜จ๊ธฐ๋Š” ์ž์ฒด ์ œ์ž‘๋˜์—ˆ๋Š”๋ฐ, ์—ฌ๋Ÿฌ ๊ฐœ์˜ ์Šคํ…Œ์ธ๋ฆฌ์Šค ๋ฐ”ํŠธ(Stainless Steel Vat) ์‚ฌ์ด์— ๋‚ด์—ด์‹ค๋ฆฌ์ฝ˜(Heat Resistant Silicone)์œผ๋กœ ๋‚ด๋ถ€๊ฐ€ ์ฑ„์›Œ์กŒ๋‹ค. ํ•ญ์˜จ๊ธฐ์˜ ์˜จ๋„์กฐ์ ˆ์„ ์œ„ํ•˜์—ฌ PVC (Polyvinyl Chloride)์šฉ์ ‘๊ธฐ์ธ KUNGSUNG์‚ฌ์˜ ๋ชจ๋ธ W-80-HOT-JET (Kongsung, 2021)์ด ์‚ฌ์šฉ๋˜์—ˆ๋‹ค. ํ•ญ์˜จ๊ธฐ์˜ ์˜จ๋„๋Š” ์˜จ๋„์„ผ์„œ NTC (Negative Temperature Coefficient of Resistance)์™€ JKCORP์‚ฌ์˜ ์ฝ˜์„ผํŠธํ˜• ๋””์ง€ํ„ธ ์˜จ๋„์กฐ์ ˆ๊ธฐ(JKCORP, 2021)๋ฅผ ์กฐํ•ฉํ•˜์—ฌ ์ž๋™์œผ๋กœ ์ œ์–ด๋˜์—ˆ๋‹ค.

Fig. 6. Temperature Chamber for PS Wire
../../Resources/KSCE/Ksce.2022.42.3.0323/fig6.png

2.3 Test No.1 ์†”๋ ˆ๋…ธ์ด๋“œ ๋ฐฐ์น˜ ๊ฐ„๊ฒฉ์— ๋”ฐ๋ฅธ ์ž์†ํˆฌ๊ณผ์œจ ๋ฏผ๊ฐ๋„

Fig. 7์€ ์†”๋ ˆ๋…ธ์ด๋“œ ํŒŒ์ดํ”„์™€ ์ œ์›์„ ๋ณด์—ฌ์ค€๋‹ค. ์†”๋ ˆ๋…ธ์ด๋“œ ํŒŒ์ดํ”„๋Š” ์†”๋ ˆ๋…ธ์ด๋“œ ๋ฐฐ์น˜ ๊ฐ„๊ฒฉ์— ๋Œ€ํ•œ ์ž์†ํˆฌ๊ณผ์œจ ๋ฏผ๊ฐ๋„๋ฅผ ์ธก์ •ํ•˜๊ธฐ ์œ„ํ•˜์—ฌ ์ œ์ž‘๋˜์—ˆ๋‹ค. ์†”๋ ˆ๋…ธ์ด๋“œ์˜ ํญ๊ณผ ๊ฐ„๊ฒฉ์€ 10 mm์ด๋‹ค. ๊ฐ€์ง„์†”๋ ˆ๋…ธ์ด๋“œ์—์„œ ์ธ๊ฐ€๋œ ์ž์†์€ ๊ฐ•์„ ์„ ํƒ€๊ณ  ํ๋ฅด๋‹ค๊ฐ€ ๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ์—์„œ ์ธก์ • ๋œ๋‹ค. Table 2๋Š” ๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ No.1์„ ๊ธฐ์ค€์œผ๋กœ ๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ์˜ ๊ฐ„๊ฒฉ์„ ๋ณด์—ฌ์ค€๋‹ค. ์ „์›๊ณต๊ธ‰์žฅ์น˜๋Š” KIKUSUI์‚ฌ์˜ ๋ชจ๋ธ PCR-500M (KIKUSUI, 2020)์„ ์‚ฌ์šฉํ•˜์˜€๋‹ค. ๊ฐ€์ง„์†”๋ ˆ๋…ธ์ด๋“œ์— ๊ต๋ฅ˜์ „์›์„ ๊ณต๊ธ‰ํ•˜์—ฌ ์ž์†์˜ ๋ณ€ํ™”์œจ์„ ๋ฐœ์ƒ์‹œ์ผฐ๋‹ค. ๊ต๋ฅ˜์ „์›์˜ ์ „์••, ์ „๋ฅ˜ ๊ทธ๋ฆฌ๊ณ  ์ฃผํŒŒ์ˆ˜๋Š” ๊ฐ๊ฐ 50 V, 0.91 A ๊ทธ๋ฆฌ๊ณ  50 Hz์ด๋‹ค.

๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ์˜ ์ „์••์€ ์ „์••์ธก์ • ๋ชจ๋ธ NI9239 (National Instruments, 2012)๊ณผ ๋ฐ์ดํ„ฐ๋กœ๊ฑฐ cDAQ-9174๋ฅผ ์กฐํ•ฉํ•˜์—ฌ ๊ณ„์ธก๋˜์—ˆ๋‹ค. ๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ์˜ ์ „์•• ์‹œ๊ฐ„ ์ด๋ ฅ์€ ์ž์ฒด ํ”„๋กœ๊ทธ๋ž˜๋ฐํ•œ LabVIEW ์ฝ”๋“œ๋ฅผ ์ด์šฉํ•˜์—ฌ ์ˆ˜์ง‘๋˜์—ˆ๋‹ค.

์ž์†ํˆฌ๊ณผ์œจ ๊ณ„์ธก์— ์‚ฌ์šฉ๋œ PS ๊ฐ•์„ ์˜ ์ธ์žฅ๊ฐ•๋„($f_{u}$)์™€ ์ง€๋ฆ„์€ ๊ฐ๊ฐ 1860 MPa์™€ 7 mm์ด๋‹ค. ๊ฐ•์„ ์˜ ์ถ•๋ฐฉํ–ฅ์‘๋ ฅ์€ ๋งŒ๋Šฅ์žฌ๋ฃŒ์‹œํ—˜๊ธฐ์„ ์‚ฌ์šฉํ•˜์—ฌ ๋‹จ๊ณ„๋ณ„๋กœ ๋„์ž…๋˜์—ˆ๋‹ค. ๊ธด์žฅ๋ฅ ์˜ ์•ฝ 40 ~ 80 %์˜ ๋ฒ”์œ„์—์„œ ์•ฝ 7 %์”ฉ ๋„์ž…์‘๋ ฅ์„ ์ฆ๊ฐ€์‹œ์ผœ๊ฐ€๋ฉด์„œ ์ด 7ํšŒ ์‹คํ—˜ํ•˜์˜€๋‹ค. ์ผ๋ฐ˜์ ์œผ๋กœ ๊ณต์šฉ์ค‘์ธ PSC์˜ ์ฆ‰์‹œ ์†์‹ค ๋ฐ ์‹œ๊ฐ„ ์†์‹ค ํ›„์— ์ž”์กด ์‘๋ ฅ์ด ๋Œ€๋žต ์ธ์žฅ๊ฐ•๋„ ๋Œ€๋น„ 50 ~ 60 %์˜ ๋ฒ”์œ„์— ์žˆ๋‹ค. ์ด๋Ÿฌํ•œ ์ด์œ ๋กœ ๊ธด์žฅ๋ฅ  ์‹คํ—˜ ๋ฒ”์œ„๊ฐ€ ๊ฒฐ์ •๋˜์—ˆ๋‹ค.

Fig. 7. Solenoid Pipe for Test No.1
../../Resources/KSCE/Ksce.2022.42.3.0323/fig7.png
Table 2. Sensing Solenoid Interval of Test No.1

Sensing Solenoid Interval (mm)

$s_{1}$

10

$s_{2}$

30

$s_{3}$

50

$s_{4}$

70

2.4 Test No. 2 ๊ฐ•์„  ์˜จ๋„๋ณ€ํ™”์— ๋”ฐ๋ฅธ ์ž์†ํˆฌ๊ณผ์œจ

๊ธด์žฅ์žฌ๋Š” ์ธ์žฅ๊ฐ•๋„์™€ ์ง€๋ฆ„์ด ๊ฐ๊ฐ 1860 MPa์™€ 7 mm์ธ ๊ฐ•์„ ์ด ์‚ฌ์šฉ๋˜์—ˆ๋‹ค. ๊ฐ•์„ ์˜ ๊ธด์žฅ๋ฅ ์€ ๋งŒ๋Šฅ์žฌ๋ฃŒ์‹œํ—˜๊ธฐ๋ฅผ ํ†ตํ•ด ๋‹จ๊ณ„๋ณ„๋กœ ๋„์ž…๋˜์—ˆ๋‹ค. ๊ฐ•์„ ๊ณผ ์†”๋ ˆ๋…ธ์ด๋“œ ํŒŒ์ดํ”„๊ฐ€ ์ด๊ฒฉ๋˜์–ด ์žˆ์œผ๋ฏ€๋กœ, ๊ฐ•์„ ์ด ๊ธด์žฅ๋˜์–ด ๋Š˜์–ด๋‚˜๋”๋ผ๋„ ๋‘ ๊ฐœ์˜ ๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ ๊ฐ„๊ฒฉ์€ ์ผ์ •ํ•˜๊ฒŒ ์œ ์ง€๋œ๋‹ค. ๊ธด์žฅ๋ฅ ์€ 25 ~ 80 %์˜ ๋ฒ”์œ„์—์„œ 15 %์”ฉ ์ฆ๊ฐ€๋˜์—ˆ๋‹ค.

Fig. 8์€ Test 2์˜ ์‹คํ—˜์„ ์œ„ํ•˜์—ฌ ์ž์ฒด ์ œ์ž‘๋œ ํ•ญ์˜จ๊ธฐ ๋‚ด๋ถ€๋ฅผ ๋ณด์—ฌ์ค€๋‹ค. ํ•ญ์˜จ๊ธฐ๋ฅผ ์‚ฌ์šฉํ•˜์—ฌ ๊ธด์žฅ์žฌ์˜ ์ฃผ๋ณ€ ์˜จ๋„๋ฅผ ์ œ์–ดํ•  ์ˆ˜ ์žˆ๋‹ค. ํ•ญ์˜จ๊ธฐ ๋‚ด๋ถ€์— ์—ดํ’์„ ๊ฐ€ํ•˜์—ฌ, ํ•ญ์˜จ๊ธฐ ๋‚ด๋ถ€์˜จ๋„๋ฅผ 25 ~ 60 ยฐC๊นŒ์ง€ ์กฐ์ ˆํ•  ์ˆ˜ ์žˆ๋‹ค. ํ•ญ์˜จ๊ธฐ ๋‚ด๋ถ€์˜จ๋„๋Š” ์˜จ๋„์ปจํŠธ๋กค๋Ÿฌ๋ฅผ ์ด์šฉํ•˜์—ฌ ์ž๋™ ์ œ์–ด๋œ๋‹ค. ํ•ญ์˜จ๊ธฐ ๋‚ด๋ถ€์˜จ๋„๋Š” NI์‚ฌ ์˜จ๋„์ธก์ • ๋ชจ๋ธ NI9219์™€ ๋ฐ์ดํ„ฐ ๋กœ๊ฑฐ cDAQ-9174 ์กฐํ•ฉ์œผ๋กœ ๊ณ„์ธก๋˜์—ˆ๋‹ค.

Fig. 8. Chamber for PS Wire
../../Resources/KSCE/Ksce.2022.42.3.0323/fig8.png

์ž์†ํˆฌ๊ณผ์œจ์€ Fig. 4์— ๋ณด์ด๋Š” ์†”๋ ˆ๋…ธ์ด๋“œ ํŒŒ์ดํ”„๋ฅผ ์‚ฌ์šฉํ•˜์—ฌ ๊ณ„์ธก๋˜์—ˆ๋‹ค. ์ „์›๊ณต๊ธ‰์žฅ์น˜๋กœ๋ถ€ํ„ฐ ๊ฐ€์ง„์†”๋ ˆ๋…ธ์ด๋“œ์— ๊ต๋ฅ˜๊ฐ€ ๊ณต๊ธ‰๋˜์—ˆ๋‹ค. ๊ณต๊ธ‰๋œ ๊ต๋ฅ˜์˜ ์ „์••, ์ „๋ฅ˜ ๊ทธ๋ฆฌ๊ณ  ์ฃผํŒŒ์ˆ˜๋Š” ๊ฐ๊ฐ 50 V, 0.91 A ๊ทธ๋ฆฌ๊ณ  50 Hz์ด๋‹ค. ๊ฐ€์ง„์†”๋ ˆ๋…ธ์ด๋“œ์—์„œ ๋ฐœ์ƒ๋œ ์ž์†์€ ๊ฐ•์„ ์„ ํƒ€๊ณ  ํ๋ฅด๋‹ค๊ฐ€ ๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ์—์„œ Eq. (3)๊ณผ ๊ฐ™์ด ๊ธฐ์ „๋ ฅ์„ ๋ฐœ์ƒ์‹œํ‚ค๊ณ , ์ข…๊ตญ์—๋Š” ๋ฐ์ดํ„ฐ๋กœ๊ฑฐ๋ฅผ ํ†ตํ•ด์„œ ๋…ธํŠธ๋ถ ์ปดํ“จํ„ฐ์— ์ „์•• ์‹œ๊ฐ„์ด๋ ฅ์œผ๋กœ ๊ธฐ๋ก๋œ๋‹ค.

2.5 Test No.3 ๊ฐ•์—ฐ์„  ์˜จ๋„๋ณ€ํ™”์— ๋”ฐ๋ฅธ ์ž์†ํˆฌ๊ณผ์œจ

๊ธด์žฅ์žฌ๋Š” SWPC 7B 12.7 mm ๊ฐ•์—ฐ์„ ์ด ์‚ฌ์šฉ๋˜์—ˆ๋‹ค. ์ž์†ํˆฌ๊ณผ์œจ์€ Fig. 5์˜ ์†”๋ ˆ๋…ธ์ด๋“œ ํŒŒ์ดํ”„๋ฅผ ์‚ฌ์šฉํ•˜์—ฌ ์‚ฐ์ •๋˜์—ˆ๋‹ค. ๊ฐ•์—ฐ์„ ์˜ ๊ธด์žฅ๋ฅ ์€ 20 ~ 75 %๊นŒ์ง€ ์•ฝ 11 % ์”ฉ ์ฆ๊ฐ€๋˜์—ˆ๋‹ค.

๊ฐ•์—ฐ์„ ์˜ ์˜จ๋„๋ณ€ํ™”์— ๋Œ€ํ•œ ์ž์†ํˆฌ๊ณผ์œจ์ด ์‚ฐ์ •๋˜์—ˆ๋‹ค. ๊ทธ ๋ฐ–์˜ ์‹คํ—˜์กฐ๊ฑด์€ ๊ฐ•์„  ์˜จ๋„๋ณ€ํ™”์— ๋”ฐ๋ฅธ ์ž์†ํˆฌ๊ณผ์œจ ์‹คํ—˜๊ณผ ๋™์ผํ•˜๋‹ค.

3. ์‹คํ—˜ ๊ฒฐ๊ณผ

3.1 Test No.1 ์†”๋ ˆ๋…ธ์ด๋“œ ๊ฐ„๊ฒฉ์— ๋”ฐ๋ฅธ ์ž์†ํˆฌ๊ณผ์œจ ์ธก์ •๊ฒฐ๊ณผ

๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ์˜ ๊ฐ„๊ฒฉ์— ๋”ฐ๋ฅธ ์ž์†ํˆฌ๊ณผ์œจ์ด ์‚ฐ์ •๋˜์—ˆ๋‹ค. Fig. 9๋Š” ๊ธด์žฅ๋ฅ ์— ๋Œ€ํ•œ ์ž์†ํˆฌ๊ณผ์œจ์˜ ์‹คํ—˜์  ๊ด€๊ณ„๋ฅผ ๋ณด์—ฌ์ค€๋‹ค. Fig. 6๊ณผ ๊ฐ™์ด 4 ์ข…๋ฅ˜์˜ ์†”๋ ˆ๋…ธ์ด๋“œ ๊ฐ„๊ฒฉ ๋ฐ 7 ๋‹จ๊ณ„์˜ ๊ธด์žฅ๋ฅ ์— ๋Œ€ํ•˜์—ฌ ์ž์†ํˆฌ๊ณผ์œจ์ด ๊ณ„์ธก๋˜์—ˆ๋‹ค. ๊ณ„์ธก๊ฒฐ๊ณผ๋กœ๋ถ€ํ„ฐ ๊ธด์žฅ๋ฅ ๊ณผ ์ž์†ํˆฌ๊ณผ์œจ์€ ์„ ํ˜• ๋น„๋ก€ํ•˜๋Š” ๊ฒƒ์ด ํ™•์ธ๋œ๋‹ค. ์†”๋ ˆ๋…ธ์ด๋“œ ๊ฐ„๊ฒฉ, $s_{1}$,์—์„œ ๊ธด์žฅ๋ฅ ์ด 42.50 % ์ฆ๊ฐ€ ์‹œ์— ์ž์†ํˆฌ๊ณผ์œจ์€ 4.29 % ์ฆ๊ฐ€ํ•˜์˜€๋‹ค. ๊ทธ๋Ÿฌ๋ฏ€๋กœ ๊ธด์žฅ๋ฅ ์— ๋Œ€ํ•œ ๊ฐ•์„ ์˜ ์ž์†ํˆฌ๊ณผ์œจ ๋ฏผ๊ฐ๋„๋Š” ์ž์†ํˆฌ๊ณผ์œจ์˜ ๋ณ€ํ™”๋Ÿ‰ 4.29 %๋ฅผ ๊ธด์žฅ๋ฅ ์˜ ๋ณ€ํ™”๋Ÿ‰ 42.50 %๋กœ ๋‚˜๋ˆ„์–ด ์–ป์„ ์ˆ˜ ์žˆ๋Š”๋ฐ, ๋Œ€๋žต 0.10์ด๋‹ค.

Fig. 10์€ ๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ ๊ฐ„๊ฒฉ์— ๋Œ€ํ•œ ์ž์†ํˆฌ๊ณผ์œจ์˜ ๊ด€๊ณ„๋ฅผ ๋ณด์—ฌ์ค€๋‹ค. ๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ ๊ฐ„๊ฒฉ์ด ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ ์ž์†ํˆฌ๊ณผ์œจ์ด ๋น„๋ก€ํ•˜์—ฌ ์ฆ๊ฐ€ํ•œ๋‹ค. ๊ธด์žฅ๋ฅ  67.83 %์—์„œ ์†”๋ ˆ๋…ธ์ด๋“œ ๊ฐ„๊ฒฉ์ด 60 mm ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ ์ž์†ํˆฌ๊ณผ์œจ์€ 46.47 % ์ฆ๊ฐ€ํ•˜์˜€๋‹ค. ์†”๋ ˆ๋…ธ์ด๋“œ ๊ฐ„๊ฒฉ์— ๋Œ€ํ•œ ๊ฐ•์„ ์˜ ์ž์†ํˆฌ๊ณผ์œจ ๋ฏผ๊ฐ๋„๋Š” 0.79์ด๋‹ค.

Fig. 9. Permeability of Magnetic Flux according to Prestressing Ratio
../../Resources/KSCE/Ksce.2022.42.3.0323/fig9.png
Fig. 10. Permeability of Magnetic Flux according to Solenoid Interval
../../Resources/KSCE/Ksce.2022.42.3.0323/fig10.png

3.2 Test No.2 ๊ฐ•์„  ์˜จ๋„๋ณ€ํ™”์— ๋”ฐ๋ฅธ ์ž์†ํˆฌ๊ณผ์œจ ์ธก์ •๊ฒฐ๊ณผ

ํŠน์ • ๊ธด์žฅ๋ฅ  ์กฐ๊ฑดํ•˜์—์„œ ์˜จ๋„๋ฅผ ๋ณ€ํ™”์‹œํ‚ค๋ฉด์„œ ์ธก์ •๋œ ์ž์†ํˆฌ๊ณผ์œจ์ด ๋น„๊ต๋˜์—ˆ๋‹ค. ์‹คํ—˜์— ์‚ฌ์šฉ๋œ ๊ธด์žฅ๋ฅ  ์ˆ˜์ค€๊ณผ ์˜จ๋„๋Š” ๊ฐ๊ฐ ์ด 5๋‹จ๊ณ„์™€ ์ด 8๋‹จ๊ณ„์ด๋‹ค. ํ•ญ์˜จ๊ธฐ๋ฅผ ํ†ตํ•˜์—ฌ 25 ~ 60 ยฐC๊นŒ์ง€ 5 ยฐC์”ฉ ์˜จ๋„๋ฅผ ๋†’์—ฌ๊ฐ€๋ฉฐ ์ž์†ํˆฌ๊ณผ์œจ์ด ์ธก์ •๋˜์—ˆ๋‹ค. Fig. 11์€ ๊ฐ•์„ ์— ๋„์ž…๋œ ๊ธด์žฅ๋ฅ ๊ณผ ์ž์†ํˆฌ๊ณผ์œจ ์‚ฌ์ด์˜ ๊ด€๊ณ„๋ฅผ ๋‚˜ํƒ€๋‚ธ๋‹ค. ๋ชจ๋“  ์˜จ๋„์—์„œ ์ž์†ํˆฌ๊ณผ์œจ์€ ๊ธด์žฅ๋ฅ ์ด ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ์„œ ์ฆ๊ฐ€ํ•œ๋‹ค. ์˜จ๋„ 30 ยฐC์—์„œ ๊ธด์žฅ๋ฅ ์ด 58.65 % ์ฆ๊ฐ€ ์‹œ์— ์ž์†ํˆฌ๊ณผ์œจ์€ 5.39 % ์ฆ๊ฐ€ํ•˜์˜€๋‹ค. ๊ธด์žฅ๋ฅ ์— ๋Œ€ํ•œ ๊ฐ•์„ ์˜ ์ž์†ํˆฌ๊ณผ์œจ ๋ฏผ๊ฐ๋„๋Š” 0.09์ด๋‹ค. ์ด๋Š” Test No. 1์—์„œ ์‚ฐ์ •๋œ ๊ธด์žฅ๋ฅ ์— ๋Œ€ํ•œ ์ž์†ํˆฌ๊ณผ์œจ ๋ฏผ๊ฐ๋„ 0.1๊ณผ ๋งค์šฐ ์œ ์‚ฌํ•œ ๊ฐ’์ด๋‹ค.

Fig. 12๋Š” ์˜จ๋„์— ๋Œ€ํ•œ ๊ฐ•์„ ์˜ ์ž์†ํˆฌ๊ณผ์œจ ๊ด€๊ณ„๋ฅผ ๋‚˜ํƒ€๋‚ธ๋‹ค. ๋ชจ๋“  ๊ธด์žฅ๋ฅ ์—์„œ ์˜จ๋„๊ฐ€ ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ ์ž์†ํˆฌ๊ณผ์œจ์€ ๊ฐ์†Œํ•˜์˜€๋‹ค. ๊ธด์žฅ๋ฅ  68.935 %์—์„œ ์˜จ๋„๊ฐ€ 35 ยฐC์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ ์ž์†ํˆฌ๊ณผ์œจ์€ 1.14 % ๊ฐ์†Œํ•˜์˜€๋‹ค. ์˜จ๋„์— ๋Œ€ํ•œ ๊ฐ•์„ ์˜ ์ž์†ํˆฌ๊ณผ์œจ ๋ฏผ๊ฐ๋„๋Š” โ€“0.03์ด๋‹ค.

Fig. 11. Permeability of Magnetic Flux according to Prestressing Ratio of PS Wire
../../Resources/KSCE/Ksce.2022.42.3.0323/fig11.png
Fig. 12. Permeability of Magnetic Flux according to Temperature of PS Wire
../../Resources/KSCE/Ksce.2022.42.3.0323/fig12.png

3.3 Test No. 3 ๊ฐ•์—ฐ์„  ์˜จ๋„๋ณ€ํ™”์— ๋‹ค๋ฅธ ์ž์†ํˆฌ๊ณผ์œจ ์ธก์ •๊ฒฐ๊ณผ

6๋‹จ๊ณ„์˜ ๊ธด์žฅ๋ฅ ์— ๋Œ€ํ•˜์—ฌ, 25 ~ 60 ยฐC๊นŒ์ง€ 5 ยฐC์”ฉ ์˜จ๋„๋ฅผ ๋ณ€ํ™”์‹œํ‚ค๋ฉฐ ์ž์†ํˆฌ๊ณผ์œจ์ด ์ธก์ •๋˜์—ˆ๋‹ค. ๊ทธ ๋ฐ–์˜ ์‹คํ—˜์˜ ์กฐ๊ฑด์€ Test No.2์˜ ๊ฐ•์„  ์˜จ๋„๋ณ€ํ™”์— ๋”ฐ๋ฅธ ์ž์†ํˆฌ๊ณผ์œจ๊ณผ ๋™์ผํ•˜๋‹ค.

Fig. 13์€ ๊ฐ•์—ฐ์„ ์˜ ๊ธด์žฅ๋ฅ ๊ณผ ์ž์†ํˆฌ๊ณผ์œจ์˜ ๊ด€๊ณ„๋ฅผ ๋ณด์—ฌ์ค€๋‹ค. ๋ชจ๋“  ์˜จ๋„์กฐ๊ฑด์—์„œ ๊ธด์žฅ๋ฅ ์— ๋Œ€ํ•œ ๊ฐ•์—ฐ์„ ์˜ ์ž์†ํˆฌ๊ณผ์œจ์€ ์„ ํ˜• ๋น„๋ก€ํ•˜์˜€๋‹ค. ์˜จ๋„ 30 ยฐC์—์„œ ๊ธด์žฅ๋ฅ  55.12 % ์ฆ๊ฐ€ ์‹œ์— ์ž์†ํˆฌ๊ณผ์œจ์€ 4.95 % ์ฆ๊ฐ€ํ•˜์˜€๋‹ค. ๊ธด์žฅ๋ฅ ์— ๋Œ€ํ•œ ๊ฐ•์—ฐ์„ ์˜ ์ž์†ํˆฌ๊ณผ์œจ ๋ฏผ๊ฐ๋„๋Š” 0.09์ด๋‹ค.

Fig. 14๋Š” ๊ฐ•์—ฐ์„ ์˜ ์˜จ๋„๋ณ€ํ™”์— ๋Œ€ํ•œ ์ž์†ํˆฌ๊ณผ์œจ์„ ๋ณด์—ฌ์ค€๋‹ค. ๋ชจ๋“  ๊ธด์žฅ๋ฅ ์—์„œ ์˜จ๋„๊ฐ€ ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ ์ž์†ํˆฌ๊ณผ์œจ์ด ๊ฐ์†Œํ•˜์˜€๋‹ค. ๊ธด์žฅ๋ฅ  64.01 %์—์„œ ์˜จ๋„๊ฐ€ 35 ยฐC ์ฆ๊ฐ€ ์‹œ์— ๊ธด์žฅ๋ฅ ์€ 0.92 % ๊ฐ์†Œํ•˜์˜€๋‹ค. ์˜จ๋„์— ๋Œ€ํ•œ ๊ฐ•์—ฐ์„ ์˜ ์ž์†ํˆฌ๊ณผ์œจ ๋ฏผ๊ฐ๋„๋Š” โ€“0.03์ด๋‹ค.

Fig. 13. Permeability of Magnetic Flux according to Prestressing Ratio of PS Strand
../../Resources/KSCE/Ksce.2022.42.3.0323/fig13.png
Fig. 14. Permeability of Magnetic Flux according to Temperature of PS Strand
../../Resources/KSCE/Ksce.2022.42.3.0323/fig14.png

3.4 ๋ถ„์„

Test No.1์—์„œ๋Š” ์†”๋ ˆ๋…ธ์ด๋“œ ๊ฐ„๊ฒฉ์— ๋Œ€ํ•˜์—ฌ ์ž์†ํˆฌ๊ณผ์œจ์˜ ๋ฏผ๊ฐ๋„๊ฐ€ ๊ฒ€ํ† ๋˜์—ˆ๋‹ค. ์†”๋ ˆ๋…ธ์ด๋“œ ๊ฐ„๊ฒฉ์ด ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ ์ž์†ํˆฌ๊ณผ์œจ์ด ์ฆ๊ฐ€ํ•˜์˜€๋‹ค. ์†”๋ ˆ๋…ธ์ด๋“œ ๊ฐ„๊ฒฉ์˜ ์ž์†ํˆฌ๊ณผ์œจ ๋ฏผ๊ฐ๋„๋Š” ๊ธด์žฅ๋ฅ ์˜ ์ž์†ํˆฌ๊ณผ์œจ ๋ฏผ๊ฐ๋„ ๋ณด๋‹ค ํ›จ์”ฌ ๋†’๋‹ค. ๊ทธ๋Ÿฌ๋ฏ€๋กœ ๊ธด์žฅ๋ฅ ๊ณผ ์ž์†ํˆฌ๊ณผ์œจ์‚ฌ์ด์˜ ๊ด€๊ณ„๋ฅผ ์ด์šฉํ•˜์—ฌ ๊ธด์žฅ๋ฅ ์„ ์‚ฐ์ •ํ•˜๊ธฐ ์œ„ํ•ด์„œ๋Š” ๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ์˜ ๊ฐ„๊ฒฉ์ด ์ผ์ •ํ•˜๊ฒŒ ์œ ์ง€๋˜์–ด์•ผ ํ•จ์„ ์•Œ ์ˆ˜ ์žˆ๋‹ค.

Test No.2์—์„œ๋Š” ์˜จ๋„๋ณ€ํ™” ๋ฐ ๊ธด์žฅ๋ฅ ์— ๋Œ€ํ•œ ๊ฐ•์„ ์˜ ์ž์†ํˆฌ๊ณผ์œจ ๋ฏผ๊ฐ๋„๊ฐ€ ๊ฒ€ํ† ๋˜์—ˆ๋‹ค. Fig. 15๋Š” ๊ฐ•์„ ์˜ ์˜จ๋„, ๊ธด์žฅ๋ฅ  ๋ฐ ์ž์†ํˆฌ๊ณผ์œจ์˜ ์ƒ๊ด€๊ด€๊ณ„๋ฅผ ๋‚˜ํƒ€๋‚ธ๋‹ค. ๊ฐ•์„ ์˜ ์ž์†ํˆฌ๊ณผ์œจ์€ ๊ธด์žฅ๋ฅ ์— ๋น„๋ก€ํ•˜๊ณ , ์˜จ๋„์— ๋ฐ˜๋น„๋ก€ํ•˜์˜€๋‹ค.

Test No.3์—์„œ๋Š” ์˜จ๋„๋ณ€ํ™” ๋ฐ ๊ธด์žฅ๋ฅ ์— ๋Œ€ํ•œ ๊ฐ•์—ฐ์„ ์˜ ์ž์†ํˆฌ๊ณผ์œจ ๋ฏผ๊ฐ๋„๊ฐ€ ๊ฒ€ํ† ๋˜์—ˆ๋‹ค. Fig. 16์€ ๊ฐ•์—ฐ์„ ์˜ ๊ธด์žฅ๋ฅ , ์˜จ๋„ ๊ทธ๋ฆฌ๊ณ  ์ž์†ํˆฌ๊ณผ์œจ์˜ ์ƒ๊ด€๊ด€๊ณ„๋ฅผ ๋‚˜ํƒ€๋‚ธ๋‹ค. Test No.2์™€ ๋งˆ์ฐฌ๊ฐ€์ง€๋กœ ๊ฐ•์—ฐ์„ ์˜ ์ž์†ํˆฌ๊ณผ์œจ์€ ๊ธด์žฅ๋ฅ ์— ๋น„๋ก€ํ•˜๊ณ , ์˜จ๋„์— ๋ฐ˜๋น„๋ก€ํ•˜์˜€๋‹ค.

Table 3์€ Test No.1๊ณผ Test No.2์—์„œ ๋„์ถœ๋œ ๊ธด์žฅ์žฌ์˜ ์ž์†ํˆฌ๊ณผ์œจ ๋ฏผ๊ฐ๋„๋ฅผ ๋ณด์—ฌ์ค€๋‹ค. ๊ฐ•์„ ๊ณผ ๊ฐ•์—ฐ์„ ์˜ ์ž์†ํˆฌ๊ณผ์œจ ๋ฏผ๊ฐ๋„๋Š” ๊ฑฐ์˜ ์ผ์น˜ํ•œ๋‹ค. ์‹œํ—˜์ฒด์˜ ๊ฐ•์ข… ๋ฐ ๊ผฌ์ž„๊ณผ ๊ฐ™์€ ๊ธฐํ•˜ ํ˜•์ƒ์ด ์ž์†ํˆฌ๊ณผ์œจ์— ๋ฏธ์น˜๋Š” ์˜ํ–ฅ์€ ๋ฏธ๋ฏธํ•œ ๊ฒƒ์œผ๋กœ ๋ณด์ธ๋‹ค.

Fig. 15. The Permeability of Magnetic Flux to Temperature and Prestressing Ratio of PS Wire
../../Resources/KSCE/Ksce.2022.42.3.0323/fig15.png
Fig. 16. The Permeability of Magnetic Flux to Temperature and Prestressing Ratio of PS Strand
../../Resources/KSCE/Ksce.2022.42.3.0323/fig16.png
Table 3. Sensitivity of Permeability of Magnetic Flux

PS Wire

PS Strand

Temperature (ยฐC)

-0.03

-0.03

Prestressing Ratio (%)

0.09

0.09

์˜จ๋„์— ๋Œ€ํ•œ ๊ฐ•์„ ์˜ ์ž์†ํˆฌ๊ณผ์œจ ๋ฏผ๊ฐ๋„๋Š” ๊ธด์žฅ๋ฅ ์˜ ์ž์†ํˆฌ๊ณผ์œจ ๋ฏผ๊ฐ๋„๋ณด๋‹ค ๋Œ€๋žต 30 %์ •๋„ ๋‚ฎ๋‹ค. ์ด๋Š” ์ž์†ํˆฌ๊ณผ์œจ์„ ๊ณ„์ธกํ•˜์—ฌ ๊ธด์žฅ๋ฅ ์„ ์ถ”์ •ํ•  ๊ฒฝ์šฐ์— ๋ฌด์‹œํ•  ์ˆ˜ ์—†๋Š” ์ •๋„์ด๋ฏ€๋กœ ํ˜„์žฅ์ ์šฉ ์‹œ ๊ฐ•์„ ์˜ ์˜จ๋„ ๊ณ„์ธก๊ณผ ๋ณด์ •์€ ๋ฐ˜๋“œ์‹œ ํ•„์š”ํ•˜๋‹ค.

4. ๊ฒฐ ๋ก 

๋ณธ ์—ฐ๊ตฌ์—์„œ๋Š” ๊ธด์žฅ๋ฅ  ๋ฐ ์˜จ๋„๋ณ€ํ™”์— ๋”ฐ๋ฅธ ๊ธด์žฅ์žฌ์˜ ์ž์†ํˆฌ๊ณผ์œจ ๋ฏผ๊ฐ๋„๊ฐ€ ์‹คํ—˜์ ์œผ๋กœ ์กฐ์‚ฌ๋˜์—ˆ๋‹ค. ๊ธด์žฅ์žฌ์˜ ์ž์†ํˆฌ๊ณผ์œจ์„ ์ถ”์ •ํ•˜๊ธฐ ์œ„ํ•ด์„œ 3์ข…๋ฅ˜์˜ ์‹คํ—˜์ด ์ˆ˜ํ–‰๋˜์—ˆ๋‹ค. Test No.1์—์„œ๋Š” ๊ฐ์ง€์†”๋ ˆ๋…ธ์ด๋“œ์˜ ๋‹ค์–‘ํ•œ ๊ฐ„๊ฒฉ ๋Œ€๋น„ ์ž์†ํˆฌ๊ณผ์œจ์ด ๊ณ„์ธก๋˜์—ˆ๋‹ค. Test No.2์™€ Test No.3์˜ ์‹คํ—˜์€ ๊ฐ๊ฐ ๊ฐ•์„ ๊ณผ ๊ฐ•์—ฐ์„ ์— ๋Œ€ํ•˜์—ฌ ๊ธด์žฅ๋ฅ  ๋ฐ ์˜จ๋„๋ณ€ํ™”์— ๋Œ€ํ•œ ์ž์†ํˆฌ๊ณผ์œจ์˜ ๋ฏผ๊ฐ๋„๊ฐ€ ๊ฒ€ํ† ๋˜์—ˆ๋‹ค. ์‹คํ—˜๊ฒฐ๊ณผ๋กœ๋ถ€ํ„ฐ ๋‹ค์Œ ๋„ค ๊ฐ€์ง€์˜ ๊ฒฐ๋ก ์— ์ด๋ฅธ๋‹ค.

์ฒซ์งธ, ์†”๋ ˆ๋…ธ์ด๋“œ ๊ฐ„๊ฒฉ์ด ์ž์†ํˆฌ๊ณผ์œจ์— ๋ฏธ์น˜๋Š” ์˜ํ–ฅ์€ ๋งค์šฐ ํฌ๋‹ค. ๊ทธ๋Ÿฌ๋ฏ€๋กœ ์ž์†ํˆฌ๊ณผ์œจ์„ ๊ณ„์ธกํ•˜์—ฌ ๊ธด์žฅ์žฌ์˜ ์‘๋ ฅ์„ ์ถ”์ •ํ•  ๊ฒฝ์šฐ์— ์†”๋ ˆ๋…ธ์ด๋“œ์˜ ๊ฐ„๊ฒฉ์„ ๊ณ ์ •ํ•˜์—ฌ์•ผ ํ•œ๋‹ค.

๋‘˜์งธ, ๊ธด์žฅ์žฌ์˜ ์ž์†ํˆฌ๊ณผ์œจ์€ ๊ธด์žฅ๋ฅ ์— ๋น„๋ก€ํ•˜๋ฉฐ, ์˜จ๋„์— ๋ฐ˜๋น„๋ก€ํ•œ๋‹ค. ๊ธด์žฅ๋ฅ ์— ๋Œ€ํ•œ ๊ฐ•์„ ๊ณผ ๊ฐ•์—ฐ์„ ์˜ ์ž์†ํˆฌ๊ณผ์œจ ๋ฏผ๊ฐ๋„๋Š” ๊ฑฐ์˜ ๋™์ผํ•˜๋‹ค.

์…‹์งธ, ์˜จ๋„๊ฐ€ ์ž์†ํˆฌ๊ณผ์œจ์— ๋ฏธ์น˜๋Š” ์ •๋„๋Š” ๊ธด์žฅ๋ฅ ์ด ์ž์†ํˆฌ๊ณผ์œจ์— ๋ฏธ์น˜๋Š” ์˜ํ–ฅ์— ๋Œ€๋žต 30 % ์ •๋„๋กœ ๋ฌด์‹œ ๋ชป ํ•  ์ˆ˜์ค€์ด๋‹ค. ํ˜„์žฅ์—์„œ ๊ธด์žฅ์žฌ์˜ ์ •ํ™•ํ•œ ์ž์†ํˆฌ๊ณผ์œจ ๊ณ„์ธก์„ ์œ„ํ•ด์„œ๋Š” ์˜จ๋„ ๊ณ„์ธก๊ณผ ์˜จ๋„๋ณด์ •์ด ๋ฐ˜๋“œ์‹œ ํ•„์š”ํ•˜๋‹ค.

๋„ท์งธ, ์˜จ๋„ ๋ฐ ๊ธด์žฅ๋ฅ ์— ๋Œ€ํ•œ ๊ฐ•์„ ๊ณผ ๊ฐ•์—ฐ์„ ์˜ ์ž์†ํˆฌ๊ณผ์œจ ๋ฏผ๊ฐ๋„๊ฐ€ ๊ฑฐ์˜ ๋™์ผํ•˜์˜€๋‹ค. ์ด๋Š” ์‹œํ—˜์ฒด์˜ ๊ฐ•์ข… ๋ฐ ๊ผฌ์ž„๊ณผ ๊ฐ™์€ ๊ธฐํ•˜ ํ˜•์ƒ์ด ์ž์†ํˆฌ๊ณผ์œจ์— ๋ฏธ์น˜๋Š” ์˜ํ–ฅ์€ ๋ฏธ๋ฏธํ•˜๋‹ค.

PS ๊ธด์žฅ์žฌ์˜ ์ž์†ํˆฌ๊ณผ์œจ, ์˜จ๋„ ๊ทธ๋ฆฌ๊ณ  ๊ธด์žฅ๋ฅ  ์‚ฌ์ด์˜ ์‹คํ—˜์  ์ƒํ˜ธ๊ด€๊ณ„๋ฅผ ๋ฏธ๋ฆฌ ์•Œ๊ณ  ์žˆ๋‹ค๋ฉด, ์˜จ๋„์™€ ์ž์†ํˆฌ๊ณผ์œจ๋งŒ์„ ๊ณ„์ธกํ•˜์—ฌ PS ๊ธด์žฅ์žฌ์˜ ๊ธด์žฅ์‘๋ ฅ์„ ์ง์ ‘ ๊ณ„์ธกํ•  ์ˆ˜ ์žˆ๋‹ค. ์ด๋Š” ๋ณ€ํ˜•๋ฅ  ๊ณ„์ธก ์—†์ด ์‘๋ ฅ์„ ์ง์ ‘ ๊ณ„์ธกํ•˜๋Š” ๋ถ„์•ผ์— ์ ์šฉ์ด ๊ฐ€๋Šฅํ•˜๋‹ค. ์˜ˆ๋ฅผ ๋“ค๋ฉด, ํฌ์ŠคํŠธํ…์…˜ PSC๊ตฌ์กฐ๋ฌผ, ๊ทธ๋ผ์šฐํŒ…ํ•œ ๋•ํŠธ ๋‚ด์— ์žˆ๋Š” ํ…๋˜, ์–ด์Šค ์•ต์ปค, ์‚ฌ์žฅ๊ต ๊ฒฝ์‚ฌ ์ผ€์ด๋ธ”, ํ˜„์ˆ˜๊ต ํ–‰์–ด ๋ฐ ์ฃผ์ผ€์ด๋ธ”, ์—˜๋ฆฌ๋ฒ ์ดํ„ฐ ๋กœํ”„ ๋“ฑ์— ํ™œ์šฉํ•  ์ˆ˜ ์žˆ๋‹ค.

์ž์†ํˆฌ๊ณผ์œจ๊ณผ ๊ธด์žฅ๋ฅ  ์‚ฌ์ด์˜ ์ด๋ก ์  ๋ฐฐ๊ฒฝ์€ ์•„์ง ํ™•๋ฆฝ๋˜์ง€ ๋ชปํ•˜์˜€์œผ๋ฏ€๋กœ, ํ–ฅํ›„ ์ด์— ๋Œ€ํ•œ ์ถ”๊ฐ€ ์—ฐ๊ตฌ๋ฅผ ๊ธฐ๋Œ€ํ•œ๋‹ค.

๊ฐ์‚ฌ์˜ ๊ธ€

์ด ์—ฐ๊ตฌ๋Š” ํ•œ๊ตญ์—ฐ๊ตฌ์žฌ๋‹จ(NRF-2018R1D1A1B07043521)์˜ ์ง€์›์„ ๋ฐ›์•˜์Šต๋‹ˆ๋‹ค.

๋ณธ ๋…ผ๋ฌธ์€ 2021 CONVENTION ๋…ผ๋ฌธ์„ ์ˆ˜์ •ยท๋ณด์™„ํ•˜์—ฌ ์ž‘์„ฑ๋˜์—ˆ์Šต๋‹ˆ๋‹ค.

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