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Journal of the Korea Concrete Institute

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




์‚ผ์„ฑ๋ถ„๊ณ„ ์‹œ๋ฉ˜ํŠธ, ์ดˆ์ŒํŒŒ์†๋„, ํ•ด์ˆ˜, ๋‹ด์ˆ˜, ์ž๊ธฐ์น˜์œ , ์žฌ๋ นํšจ๊ณผ
Ternary blended cement, Ultrasonic pulse velocity, Sea-water, Tap-water, Self-healing, Age-effect

1. ์„œ ๋ก 

๋ณดํ†ตํฌํ‹€๋žœ๋“œ ์‹œ๋ฉ˜ํŠธ(ordinary Portland cement; OPC)๋ฅผ ๊ธฐ ๋ฐ˜์œผ๋กœ ํ•˜๋Š” ์‚ผ์„ฑ๋ถ„๊ณ„ ์‹œ๋ฉ˜ํŠธ(ternary blended cement; TBC) ๋Š” OPC์˜ ์ผ๋ถ€๋Š” ํ”Œ๋ผ์ด์• ์‹œ(fly ash; FA), ๊ณ ๋กœ์Šฌ๋ž˜๊ทธ ๋ฏธ๋ถ„ ๋ง(ground granulated blast furnace slag; GGBFS), ์‹ค๋ฆฌ์นด ํ“ธ (silica fume; SF) ๋“ฑ์˜ ์‚ฐ์—…๋ถ€์‚ฐ๋ฌผ์„ ์น˜ํ™˜ํ•œ ์‹œ๋ฉ˜ํŠธ์ด๋‹ค. ์ด๋Ÿฌ ํ•œ TBC๋Š” OPC์˜ ์‚ฌ์šฉ๋Ÿ‰์„ ์ค„์ด๊ณ , ์‚ฐ์—…๋ถ€์‚ฐ๋ฌผ์˜ ํ™œ์šฉ์„ ํ†ต ํ•ด, ์‚ฐ์—…๋ถ€์‚ฐ๋ฌผ์˜ ์žฌ์ฒ˜๋ฆฌ์™€ ๋งค๋ฆฝ ๋“ฑ์˜ ํ๊ธฐ๊ณผ์ •์—์„œ ๋ฐœ์ƒํ•˜ ๋Š” ํ™˜๊ฒฝ์˜ค์—ผ๊ณผ ๋น„์šฉ์„ ์ €๊ฐํ•˜๊ณ  ๊ฑด์„ค์žฌ๋ฃŒ์˜ ํ™œ์šฉ๋ถ„์•ผ์™€ ์„ฑ๋Šฅ ํ–ฅ์ƒ์„ ํ•จ๊ป˜ ๊ณ ๋ คํ•  ์ˆ˜ ์žˆ๋Š” ์‹œ๋ฉ˜ํŠธ๋กœ ๋งŽ์€ ์—ฐ๊ตฌ๊ฐ€ ๋˜๊ณ  ์žˆ๋‹ค. ํŠนํžˆ TBC๋Š” OPC์˜ ์‚ฌ์šฉ๋Ÿ‰์„ ์ค„์ž„์œผ๋กœ์จ OPC์˜ ์ œ์กฐ์‹œ ๋ฐœ ์ƒ๋˜๋Š” ์ž์—ฐํ›ผ์†, ๋ถ„์ง„๋ฐœ์ƒ, ์ด์‚ฐํ™”ํƒ„์†Œ ๋“ฑ์˜ ์˜จ์‹ค๊ฐ€์Šค ๋ฐฐ์ถœ, ์†Œ์„ฑ๊ณผ์ • ๋“ฑ์˜ ๊ณ ์—๋„ˆ์ง€ ์†Œ๋น„ ๋“ฑ์˜ ํ™˜๊ฒฝ๋ฌธ์ œ๋ฅผ ์™„ํ™”ํ•  ์ˆ˜ ์žˆ ๋Š” ์นœํ™˜๊ฒฝ ์‹œ๋ฉ˜ํŠธ๋กœ ์ฃผ๋ชฉ๋ฐ›๊ณ  ์žˆ๋‹ค.

์ง€๊ธˆ๊นŒ์ง€์˜ ์„ ํ–‰์—ฐ๊ตฌ์—์„œ TBC๋Š” ์‚ฐ์—…๋ถ€์‚ฐ๋ฌผ๊ณผ ๊ฐ™์€ ๋‹ค์–‘ ํ•œ ํ˜ผํ™”์žฌ๋ฃŒ๊ฐ€ ๋ฐฐํ•ฉ์— ์‚ฌ์šฉ๋˜๊ณ  ์žˆ๋‹ค(Jones et al., 1997; Bรกgel, 1998; Khan et al., 2000; Kim et al., 2012; Lee and Yoon, 2013). ์ด๋Ÿฌํ•œ ๋‹ค์–‘ํ•œ ํ˜ผํ™”์žฌ๋ฃŒ๋ฅผ ์‚ฌ์šฉํ•œ TBC๋Š” ์„œ๋กœ ๋‹ค๋ฅธ ํ˜ผํ™”์žฌ ๋ฃŒ๋“ค์˜ ์ƒํ˜ธ๋ณด์™„ํšจ๊ณผ์™€ ์ถฉ์ „ํšจ๊ณผ์— ์˜ํ•ด ์„ฑ๋Šฅ ํ–ฅ์ƒ์„ ํ†ตํ•ด ๋‹ค์–‘ํ•œ ์žฅ์ ์„ ๋‚˜ํƒ€๋‚ด๊ณ  ์žˆ๋‹ค. ํŠนํžˆ ์—ผํ•ด์ €ํ•˜์„ฑ๊ณผ ํ™ฉ์‚ฐ์—ผ ์ € ํ•ญ์„ฑ์˜ ์ฆ๋Œ€, ์•Œ์นผ๋ฆฌ ์‹ค๋ฆฌ์นด ๋ฐ˜์‘์˜ ์–ต์ œ, ์žฅ๊ธฐ๊ฐ•๋„์˜ ์ฆ๊ฐ€ ๋“ฑ ์˜ ์šฐ์ˆ˜ํ•œ ํŠน์„ฑ์ด ๋ฐœ๊ฒฌ๋˜์—ˆ๋‹ค(Jones et al., 1997; Kim et al., 2012; Jeong et al., 2015). ๋˜ํ•œ ๊ธฐ์กด์˜ ์—ฐ๊ตฌ๊ฒฐ๊ณผ๋ฅผ ํ†ตํ•ด ๋‹ค์–‘ ํ•œ ๋…ธ์ถœํ™˜๊ฒฝ๊ณผ ๋ฏธ์„ธ๊ตฌ์กฐ ๋“ฑ์— ๋Œ€ํ•œ ์—ฐ๊ตฌ๋„ ๋งŽ์ด ์ด๋ฃจ์–ด์ง€๊ณ  ์žˆ๋‹ค(Erdem and Kฤฑrca, 2008; Turk, 2012; Bohรกฤ et al., 2014; Berodier and Scrivener, 2015). ๊ทธ๋Ÿฌ๋‚˜ ์ „๋ฐ˜์ ์œผ๋กœ TBC์˜ ๋ฐฐ ํ•ฉํŠน์„ฑ์ด๋‚˜ ํ˜ผํ™”์žฌ๋ฃŒ์˜ ๋ฐฐํ•ฉ์— ๋”ฐ๋ฅธ ๋‚ด๊ตฌ์„ฑ์— ์—ฐ๊ตฌ๊ฐ€ ์ง‘์ค‘๋˜ ์–ด ์žˆ์–ด ์ƒ๋Œ€์ ์œผ๋กœ ์ž๊ธฐ์น˜์œ ์— ๋Œ€ํ•œ ์—ฐ๊ตฌ๋Š” ๋ฏธํกํ•˜๋‹ค.

์ž๊ธฐ์น˜์œ ๋Š” ๊ท ์—ด์ด ๋ฐœ์ƒํ•œ ์‹œํ—˜์ฒด์—์„œ ์ผ์ • ํญ ์ดํ•˜์˜ ๊ท  ์—ด์ด ์ ์ •ํ•œ ํ™˜๊ฒฝ์— ๋…ธ์ถœ๋˜๋ฉด ๊ท ์—ด์ด ์ฒœ์ฒœํžˆ ๋‹ซํžˆ๋Š” ํ˜„์ƒ์ด ๋‹ค. ์ด๋Ÿฌํ•œ ์ž๊ธฐ์น˜์œ  ํ˜„์ƒ์— ๋Œ€ํ•œ ์ง€๊ธˆ๊นŒ์ง€์˜ ๊ตญ๋‚ด์™ธ ์—ฐ๊ตฌ์— ์˜ ํ•˜๋ฉด, ๊ท ์—ด๋ฉด์— ๋…ธ์ถœ๋œ ๋ฏธ์ˆ˜ํ™” ์ž…์ž๋“ค์˜ ์žฌ์ˆ˜ํ™”(re-hydration) ๋˜๋Š” ๊ท ์—ด๋ฉด์— ๊ฒฐ์ •์„ฑ์žฅ(recrystalized) ๋“ฑ์— ์˜ํ•ด ๊ท ์—ด์ด ๋‹ซํžˆ๋Š” ๊ฒƒ์ด ๋‹ค. ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋Š” ๋‹ค์–‘ํ•œ ํ˜ผํ™”์žฌ๋ฃŒ(cementitious materials)์™€, ๋ฐ•ํ…Œ๋ฆฌ์•„๋‚˜ ์บก์Š๊ณผ ๊ฐ™์€ ์ž๊ธฐ์น˜์œ  ๋ฌผ์งˆ, ์˜จ๋„, ๋…ธ์ถœ์‹œ๊ฐ„, ๊ฑด์Šต ๋ฐ˜๋ณต ๋“ฑ ๋‹ค์–‘ํ•œ ํ™˜๊ฒฝ์กฐ๊ฑด๊ณผ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ์ธก์ •ํ•˜๊ธฐ ์œ„ํ•œ ์ˆ˜๋งŽ์€ ๋ฐฉ๋ฒ• ๋“ฑ์— ๋Œ€ํ•œ ์—ฐ๊ตฌ๊ฐ€ ์žˆ์—ˆ๋‹ค(Wu et al., 2012; Tang et al., 2015; Huang et al., 2013; Palin et al., 2015, Ferrara et al., 2014; Qian et al., 2010; Tittelboom et al., 2012). ๋‹ค์–‘ํ•œ ํ˜ผํ™” ์žฌ๋ฃŒ๋ฅผ ๋ฐฐํ•ฉํ•œ ์‹œํ—˜์ฒด์˜ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ์— ๋Œ€ํ•œ ์—ฐ๊ตฌ๋Š” ์ž๊ธฐ ์น˜์œ  ํšจ๊ณผ๋ฅผ ๋†’์ด๊ธฐ ์œ„ํ•œ ๋ฐฉ๋ฒ•์œผ๋กœ ์žฌ์ˆ˜ํ™” ๋˜๋Š” ๊ฒฐ์ •์„ฑ์žฅ์„ ์ด‰์ง„ํ•  ๋ชฉ์ ์œผ๋กœ GGBFS, FA, SF ๋˜๋Š” metakaolin ๋“ฑ์„ ์‚ฌ์šฉ ํ•˜์˜€๋‹ค(Sahmaran et al., 2013; Tang et al., 2015; Wu et al., 2012). ๋˜ํ•œ ๋Œ€๋ถ€๋ถ„์˜ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋Š” ๋‹ด์ˆ˜์— ๋…ธ์ถœ๋˜๋Š” ํ™˜๊ฒฝ ์— ๋Œ€ํ•œ ์—ฐ๊ตฌ๊ฐ€ ์ค‘์‹ฌ์ด์˜€์œผ๋ฉฐ, ์ตœ๊ทผ์— ํ•ด์ˆ˜์— ๋…ธ์ถœ๋œ ์‹œํ—˜์ฒด์˜ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ์— ๋Œ€ํ•œ ์—ฐ๊ตฌ๊ฐ€ ์ผ๋ถ€ ์žˆ์—ˆ๋‹ค(Palin et al., 2015). ๋”ฐ ๋ผ์„œ ๋‹ด์ˆ˜์™€ ๋น„๊ตํ•˜์—ฌ ์ƒ๋Œ€์ ์œผ๋กœ ํ•ด์ˆ˜์— ๋…ธ์ถœ๋œ ์‹œํ—˜์ฒด์˜ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ๊ฒ€ํ† ํ•œ ์—ฐ๊ตฌ๋Š” ์—ฐ๊ตฌ๊ฐ€ ์ง„ํ–‰๋˜๊ณ  ์žˆ์œผ๋ฉฐ, ํŠน ํžˆ ์žฌ๋ นํšจ๊ณผ์™€ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ๊ณ ๋ คํ•œ ์—ฐ๊ตฌ๋Š” ๋“œ๋ฌผ๋‹ค.

๋ณธ ์—ฐ๊ตฌ๋Š” OPC, GGBFS ๊ทธ๋ฆฌ๊ณ  FA๋ฅผ ํ˜ผํ•ฉํ•œ ์‚ผ์„ฑ๋ถ„๊ณ„ ์‹œ ๋ฉ˜ํŠธ๋กœ ์ œ์ž‘ํ•œ ํŽ˜์ด์ŠคํŠธ(paste) ์‹œํ—˜์ฒด๋ฅผ ๋‹ด์ˆ˜(tap-water)์™€ ํ•ด์ˆ˜(sea-water)์— ์นจ์ง€ํ•˜์—ฌ ์ดˆ์ŒํŒŒ์†๋„(ultrasonic pulse velocity; UPV) ์ธก์ •๋ฐฉ๋ฒ•์„ ์ด์šฉํ•˜์—ฌ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ์ธก์ •ํ•˜์˜€๋‹ค. ๋˜ํ•œ ์žฌ๋ น์— ๋”ฐ๋ฅธ UPV์ฆ๊ฐ€์œจ์„ ๊ณ ๋ คํ•œ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋„ ์ธก์ •ํ•˜์˜€๋‹ค.

2. ์žฌ๋ฃŒ ๋ฐ ์‹คํ—˜

2.1. ์žฌ๋ฃŒ

๊ณ ๋กœ์Šฌ๋ž˜๊ทธ ๋ฏธ๋ถ„๋ง(GGBFS)์€ ๊ตญ๋‚ด 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, FA and OPC

GGBFS FA OPC

Chemical components (%) SiO2 35.30 71.00 21.32
Al2O3 12.58 16.92 5.61
Fe2O3 0.79 3.73 3.12
CaO 41.30 2.97 61.72
MgO 3.19 0.95 3.94
TiO2 0.70 - -
MnO 0.22 - -
SO3 4.75 0.61 2.51
K2O 0.63 1.22 0.79

Physical properties Ig-loss(%) 0.32 2.86 2.31
Blain(cm2/g) 4200 3900 3300
Density(g/mm3) 0.0028 0.0023 0.00315

์‹œํ—˜์ฒด๋ฅผ ์นจ์ง€ํ•˜๊ธฐ ์œ„ํ•ด ์ผ๋ฐ˜ ๋‹ด์ˆ˜(Tap-water, TW)์™€ ํ•ด์ˆ˜ (Sea-water, SW)๋ฅผ ์‚ฌ์šฉํ•˜์˜€๊ณ , ํ•ด์ˆ˜๋Š” ๋ถ€์‚ฐ์‹œ ์†ก์ • ํ•ด๋ณ€์—์„œ ์ฑ„์ทจํ•˜์˜€๋‹ค. ํ•ด์ˆ˜์˜ ๊ตฌ์„ฑ์„ฑ๋ถ„์€ ICP-AES(Inductively Coupled Plasma-Atomic Emission Spectrometry)๋ถ„์„์„ ํ†ตํ•ด Table 2 ์— ๋‚˜ํƒ€๋‚ด์—ˆ๋‹ค.

Table 2

Components of sea water(ppm)

Ca2+ K+ Mg2+ Na+ Cl- SO4 2-

400ยฑ50 440ยฑ60 1,200ยฑ110 8,400ยฑ140 21,000ยฑ210 2,500ยฑ90

2.2. ์‹œํ—˜์ฒด์˜ ์ œ์ž‘ ๋ฐ ์‹คํ—˜๋ฐฉ๋ฒ•

ํŽ˜์ด์ŠคํŠธ ์‹œํ—˜์ฒด๋Š” KS L 5109 ๋ฐฉ๋ฒ•์˜ ๋”ฐ๋ผ ๋ฐฐํ•ฉํ•˜์˜€๊ณ , ๋ฌผ- ๊ฒฐํ•ฉ์žฌ ๋น„(W/b)๋Š” 0.5์ด๋‹ค. OPC-GGBFS-FA์˜ ์‚ผ์„ฑ๋ถ„๊ณ„ ์‹œ ํ—˜์ฒด์˜ ์ž๊ธฐ์น˜์œ  ํŠน์„ฑ์„ ์‚ดํŽด๋ณด๊ธฐ ์œ„ํ•ด 20ยฐC์˜ ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜ ์— ์นจ์ง€ํ•˜์˜€๋‹ค. GGBFS์™€ FA๋Š” OPC ์ค‘๋Ÿ‰์— ๋Œ€ํ•ด ์ผ์ • ๋น„์œจ ์น˜ํ™˜ํ•˜์˜€์œผ๋ฉฐ, ์ž์„ธํ•œ ์น˜ํ™˜์œจ์€ Table 3์— ๋‚˜ํƒ€๋‚ด์—ˆ๋‹ค.

Table 3

Mix properties(wt %)

OPC GGBFS FA

OPC 100
H8-1 80 20 0
H8-2 80 15 5
H8-3 80 10 10
H8-4 80 5 15
H8-5 80 0 20

H6-1 60 40 0
H6-2 60 30 10
H6-3 60 20 20
H6-4 60 10 30
H6-5 60 0 40

H4-1 40 60 0
H4-2 40 45 15
H4-3 40 30 30
H4-4 40 15 45
H4-5 40 0 60

์ดˆ์ŒํŒŒ ์ธก์ •์šฉ ๋ชฐ๋“œ๋Š” 40 ร— 40 ร— 160 mm3์„ ์‚ฌ์šฉํ•˜์˜€๊ณ , 50 ร— 50 ร— 50 mm3๋ฅผ ์ œ์ž‘ํ•˜์—ฌ ๊ฐ•๋„ ๋ฐ SEM๊ณผ XRD ์‹œ๋ฃŒ ์ œ์ž‘์— ์‚ฌ์šฉํ•˜์˜€๋‹ค. ๊ฐ๊ฐ์˜ ์žฌ๋ฃŒ๋ฅผ ๋ฐฐํ•ฉ ํ›„ ๋ชฐ๋“œ์— ํƒ€์„คํ•˜๊ณ  ์˜จ๋„ 23ยฑ2ยฐC์˜ ์ˆ˜์กฐ์— ๋ณด๊ด€ํ•œ๋‹ค. 24์‹œ๊ฐ„ ํ›„ ๋ชฐ๋“œ๋ฅผ ์ œ๊ฑฐํ•˜๊ณ  ์˜จ๋„ 23ยฑ2ยฐC์˜ ์ˆ˜์กฐ์— 28์ผ๊นŒ์ง€ ๋ณด๊ด€ํ•˜์˜€๋‹ค. 28์ผ ํ›„ ์‹œํ—˜์ฒด๋ฅผ ํ•ด ์ˆ˜์™€ ๋‹ด์ˆ˜์— ์นจ์ง€ํ•˜์—ฌ ํ•ญ์˜จํ•ญ์Šต๊ธฐ์— 20ยฑ2ยฐC์˜ ์˜จ๋„๋กœ ๋ณด๊ด€ ํ•œ๋‹ค. ์‹œํ—˜์ฒด๋ฅผ ์นจ์ง€ํ•œ ํ•ด์ˆ˜์™€ ๋‹ด์ˆ˜๋Š” 1์ฃผ๋งˆ๋‹ค ํ•œ ๋ฒˆ์”ฉ ๊ต์ฒด ํ•˜์˜€๋‹ค.

๋ณธ ์—ฐ๊ตฌ์—์„œ๋Š” ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ๊ฒ€ํ† ํ•˜๋Š” ๋ฐฉ๋ฒ•์œผ๋กœ ์ดˆ์ŒํŒŒ ์†๋„(ultrasonic pulse velocity, UPV)๋ฅผ ์ธก์ •ํ•˜์˜€๋‹ค. UPV๋ฅผ ์‚ฌ์šฉํ•œ ๋ฐฉ๋ฒ•์€ ์‹œํ—˜์ฒด์˜ ๋‚ด๋ถ€ ์ƒํƒœ๋ฅผ ๊ฐ„์ ‘์ ์œผ๋กœ ํ™•์ธํ•  ์ˆ˜ ์žˆ๋Š” ๋ฐฉ๋ฒ• ์ค‘ ํ•˜๋‚˜๋กœ ๋„๋ฆฌ ์‚ฌ์šฉ๋˜๋Š” ๋ฐฉ๋ฒ•์ด๋‹ค. ๋˜ํ•œ ์ผ๋ถ€ ์ž๊ธฐ ์น˜์œ  ํšจ๊ณผ๋ฅผ ์—ฐ๊ตฌ์—์„œ ์ž๊ธฐ์น˜์œ ๋ฅผ ์ธก์ •ํ•˜๋Š” ๋ฐฉ๋ฒ•์œผ๋กœ ์‚ฌ์šฉ๋˜ ๊ณ  ์žˆ๋Š” ๋ฐฉ๋ฒ• ์ค‘ ํ•˜๋‚˜์ด๋‹ค(Zhong and Yao, 2008). UPV๋Š” ๊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˜ UPV๋Š” ์–‘์ƒ 28์ผ์—์„œ ์ˆ˜์กฐ์—์„œ ๊บผ๋‚ธ ์‹œํ—˜์ฒด ํ‘œ๋ฉด์˜ ๋ฌผ์„ ํก์ˆ˜์ฒœ์œผ ๋กœ ๋‹ฆ์•„ ์ œ๊ฑฐํ•˜๊ณ  ์ดˆ๊ธฐ UPV ๊ฐ’์„ ์ธก์ •(UPVINT)ํ•œ๋‹ค. ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด(uncracked specimens)์˜ ๊ฒฝ์šฐ ๊ทธ๋Œ€ ๋กœ ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ๊ฐ๊ฐ์˜ ์˜จ๋„๋ณ„๋กœ ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด ์นจ์ง€ํ•œ๋‹ค. ์ž๊ธฐ์น˜์œ  ์ธก์ • ์‹œํ—˜์ฒด๋Š” UPVINT ์ธก์ • ํ›„ 3์  ํœจ์‹œํ—˜์„ ํ†ตํ•ด ์‹œํ—˜์ฒด์˜ ์ค‘์•™๋ถ€์— ๋‹จ์ผ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ๋‹ค. ๊ท ์—ด์€ ์‹œํ—˜์ฒด ์˜ ํ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 (ลžahmaran et al., 2008). ๋ณธ ์—ฐ๊ตฌ์—์„œ๋Š” ๋ฐœ์ƒ๋œ ๊ท ์—ด์˜ ํญ์ด 300 ฮผm ์ดํ•˜์ธ ์‹œํ—˜์ฒด๋งŒ์„ ์„ ํƒํ•˜์˜€๋‹ค. ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œ ํ—˜์ฒด(cracked specimens)์— ๋ฐœ์ƒ๋œ ๊ท ์—ด์„ ํ™•์ธํ•˜๊ณ  UPV๋ฅผ ์ธก์ •(UPVCRK)ํ•œ๋‹ค.

์ดํ›„ ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ์นจ์ง€๋œ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜ ์ฒด์™€ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด ๋ชจ๋‘ ์นจ์ง€ 30์ผ(UPV30)๊ณผ 60์ผ (UPV60)์—์„œ ๊ฐ๊ฐ ์ดˆ์ŒํŒŒ๋ฅผ ์ธก์ •ํ•œ๋‹ค.

3. ๊ฒฐ๊ณผ ๋ฐ ํ† ์˜

Fig. 1์€ ์žฌ๋ น 28์ผ, 63์ผ(์นจ์ง€ 30์ผ), 91์ผ(์นจ์ง€ 60์ผ)์—์„œ ์ธก์ •ํ•œ ๊ฐ•๋„์™€ UPV์˜ ๊ด€๊ณ„๋ฅผ ๋‚˜ํƒ€๋‚ธ ๊ฒƒ์ด๋‹ค. ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜ ๋ชจ ๋‘ ์žฌ๋ น์ด ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ ๊ฐ•๋„์™€ UPV๊ฐ€ ์ฆ๊ฐ€ํ•˜๋Š” ์„ ํ˜•๊ด€๊ณ„ ๋ฅผ ๋ณด์ธ๋‹ค(Zhong and Yao, 2008). ์ด๋Š” ์นจ์ง€ ํ™˜๊ฒฝ์—์„œ ์‹œํ—˜์ฒด ๋‚ด๋ถ€์— ๋ฏธ์ˆ˜ํ™” GGBFS์™€ FA์˜ ์ˆ˜ํ™”๊ฐ€ ์ฒœ์ฒœํžˆ ์ง„ํ–‰๋˜๋ฉด์„œ ๊ฐ• ๋„๊ฐ€ ์ฆ๊ฐ€ํ•˜๊ณ , ์ด์—๋”ฐ๋ผ UPV๋„ ์ฆ๊ฐ€ํ•˜๋Š” ๊ฒƒ์ด๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ GGBFS ์น˜ํ™˜์œจ์ด ๊ฐ์†Œํ•˜๊ณ  FA ์น˜ํ™˜์œจ์ด ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ ๊ฐ•๋„ ๋Š” ์ ์ฐจ ๊ฐ์†Œํ•˜๋Š” ๊ฒฝํ–ฅ์„ ๋ณด์ธ๋‹ค. ์ด๋Š” H8 ์‹œํ—˜์ฒด(H8-1 > H8-2 > H8-3 > H8-4 > H8-5), H6 ์‹œํ—˜์ฒด(H6-1 > H6-2 > H6-3 > H6-4 > H6-5) ๊ทธ๋ฆฌ๊ณ  H4 ์‹œํ—˜์ฒด(H4-1 > H4-2 > H4-3 > H4-4 > H4-5)์—์„œ ๋™์ผํ•œ ๊ฒฝํ–ฅ์œผ๋กœ ๋‚˜ํƒ€๋‚˜๊ณ  ์žˆ์œผ๋ฉฐ, ์ธก์ •์žฌ ๋ น(28์ผ, 63์ผ, 91์ผ) ๋ชจ๋‘์—์„œ๋„ ์œ ์‚ฌํ•œ ๊ฐ์†Œํ˜„์ƒ์„ ๋ณด์ธ๋‹ค. ์ด๋Š” ๋™์ผํ•œ ์นจ์ง€ํ™˜๊ฒฝ์—์„œ ์ƒ๋Œ€์ ์œผ๋กœ FA ๋ณด๋‹ค GGBFS์˜ ๋†’ ์€ ์ˆ˜ํ™”๋ฐ˜์‘์„ฑ์ด ๊ฐ•๋„ํ–ฅ์ƒ๊ณผ ์น˜๋ฐ€ํ•œ ๋ฐ˜์‘์ƒ์„ฑ๋ฌผ์งˆ์˜ ํ˜•์„ฑ ๋•Œ ๋ฌธ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค. ๋˜ํ•œ H4 > H6 > H8 ์ˆœ์„œ๋กœ ์žฌ๋ น์ด 91์ผ๊นŒ ์ง€ ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ GGBFS์™€ FA ํ˜ผํ•ฉ๋ฅ ์— ๋”ฐ๋ฅธ ๊ฐ•๋„ ์ฆ๊ฐ€์œจ (์ง์„ ์˜ ๊ธฐ์šธ๊ธฐ)๊ฐ€ ๊ฐ€ํŒŒ๋ฅด๊ฒŒ ๋‚˜ํƒ€๋‚˜๊ณ  ์žˆ์œผ๋ฉฐ ์ด๋Š” GGBFS์™€ FA๊ฐ€ OPC์™€ ๋น„๊ตํ•˜์—ฌ ์ƒ๋Œ€์ ์œผ๋กœ ๋Š๋ฆฐ ์ˆ˜ํ™”๋ฐ˜์‘ ๋•Œ๋ฌธ์œผ๋กœ ์ƒ๊ฐ๋œ๋‹ค.

Fig. 1

Relationship between compressive strength and UPV

JKSMI-20-10_F1.jpg

๊ทธ๋Ÿฌ๋‚˜ ํ•ด์ˆ˜(SW)์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด์˜ ๊ฐ•๋„๊ฐ€ ๋‹ด์ˆ˜(TW)์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด๋“ค ๋ณด๋‹ค ์•ฝ 1.8~17.1% ์ž‘๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ์ด๋Š” ํ•ด ์ˆ˜์— ํฌํ•จ๋˜์–ด ์žˆ๋Š” ๋‹ค์–‘ํ•œ ์œ ๋ฌด๊ธฐ์งˆ ์„ฑ๋ถ„๋“ค์ด ์‹œํ—˜์ฒด์˜ ํ‘œ ๋ฉด์— ์นจ์ „ ๋˜๋Š” ๋‚ด๋ถ€๋กœ ์นจํˆฌํ•˜์—ฌ ๋ฐ˜์‘์ƒ์„ฑ๋ฌผ์งˆ์˜ ํ™”ํ•™์  ๊ตฌ ์กฐ๋ฅผ ๋ณ€ํ™”์‹œ์ผœ ๊ฐ•๋„ ๊ฐ์†Œ๋ฅผ ์œ ๋ฐœํ•˜๋Š” ๊ฒƒ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค. ์ด๋Ÿฌ ํ•œ ๊ฐ•๋„ ๊ฐ์†Œ๊ฒฝํ–ฅ์€ H8, H6, ๊ทธ๋ฆฌ๊ณ  H4์˜ ๋ชจ๋“  ์‹œํ—˜์ฒด์—์„œ ๋Œ€ ์ฒด์ ์œผ๋กœ ์œ ์‚ฌํ•œ ๊ฐ์†Œ๊ฒฝํ–ฅ์„ฑ์„ ๋ณด์ธ๋‹ค. ๋˜ํ•œ H4์˜ ๊ฒฝ์šฐ ์žฌ๋ น 28์ผ์—์„œ ์ƒ๋Œ€์ ์œผ๋กœ H8๋ณด๋‹ค ๋‚ฎ์€ ๊ฐ•๋„์™€ UPV๋ฅผ ๋‚˜ํƒ€๋‚ด์ง€ ๋งŒ ์žฌ๋ น์ด ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ ๊ฐ€ํŒŒ๋ฅธ UPV ์ฆ๊ฐ€๋ฅผ ๋‚˜ํƒ€๋‚ด๊ณ  ์žˆ๋‹ค. H4์˜ 91์ผ ์‹œํ—˜์ฒด์ค‘ ์ผ๋ถ€ ์‹œํ—˜์ฒด๋Š” H8๋ณด๋‹ค ๋” ํฐ ๊ฐ•๋„๋ฅผ ๋‚˜ ํƒ€๋‚ด์ง€๋งŒ UPV ๊ฐ’์€ ์ƒ๋Œ€์ ์œผ๋กœ ๋‚ฎ๊ฒŒ ๋‚˜ํƒ€๋‚˜๊ณ  ์žˆ๋Š”๋ฐ, ์ด๋Š” ๋ฏธ ์ˆ˜ํ™” GGBFS์™€ FA์˜ ์ถฉ์ง„ํšจ๊ณผ์— ๊ธฐ์ธํ•˜๋Š” ๊ฒƒ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค.

Fig. 2๋Š” TBC์˜ ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด์— ๋Œ€ํ•œ UPV ์ธก์ • ๊ฒฐ๊ณผ๋ฅผ ๋‚˜ํƒ€๋‚ธ ๊ฒƒ์ด๋‹ค. ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ๊ท ์—ด์„ ๋ฐœ ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด์™€ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด ๋ชจ๋‘ ๊ฐ๊ฐ ์˜ UPV ์ธก์ •์‹œ์ ์—์„œ ์ธก์ •ํ•œ ๊ฐ’์€ OPC์˜ UPV ๋ณด๋‹ค ์ž‘๊ฒŒ ๋‚˜ ํƒ€๋‚ฌ๋‹ค. ์ด๋Š” OPC 100%์ธ ์‹œํ—˜์ฒด๋ณด๋‹ค ํ˜ผํ™”์žฌ๋ฃŒ์ธ GGBFS ์™€ FA๋ฅผ ์น˜ํ™˜ํ•˜์˜€์„ ๋•Œ ์ƒ๋Œ€์ ์œผ๋กœ OPC ๋ณด๋‹ค ๋Š๋ฆฐ ์ˆ˜ํ™”๋ฐ˜์‘ ๊ณผ ๋ฏธ์ˆ˜ํ™” ์ž…์ž๋“ค์˜ ์˜ํ–ฅ์— ์˜ํ•ด ์น˜๋ฐ€ํ•œ ์กฐ์ง์˜ ํ˜•์„ฑ์ด ์ง€์—ฐ ๋˜๊ธฐ ๋•Œ๋ฌธ์ด๋‹ค(Berodier and Scrivener, 2015).

Fig. 2

UPV results

JKSMI-20-10_F2.jpg

๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด ๋ชจ๋‘(Fig. 2(a)~(d)), OPC์˜ ๋น„์œจ์ด 80%(H8 sereis)์—์„œ 40%(H4 series)๋กœ ๊ฐ์†Œํ•จ์— ๋”ฐ๋ผ ์žฌ๋ น 28์ผ(UPVINT), ์นจ์ง€ 30์ผ(UPV30)๊ณผ 60์ผ(UPV60)์—์„œ ์˜ UPV๊ฐ€ ๊ฐ์†Œํ•˜์˜€๋‹ค. ๋˜ํ•œ ๋™์ผํ•œ OPC ๋น„์œจ์—์„œ GGBFS-FA ์˜ ํ˜ผํ•ฉ๋น„์— ๋”ฐ๋ฅธ UPV ํŠน์„ฑ์€, GGBFS์˜ ์น˜ํ™˜์œจ์ด ๊ฐ์†Œํ•จ์— ๋”ฐ๋ผ(FA ์น˜ํ™˜์œจ์ด ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ) UPV๋Š” ๊ฐ์†Œํ•˜์˜€๋‹ค. 40% OPC์˜ H4 series > 60% OPC์˜ H6 series > 80% OPC์˜ H8 series ์ˆœ์„œ๋กœ GGBFS-FA ์น˜ํ™˜์œจ์˜ ๋น„์— ๋”ฐ๋ฅธ UPV ๊ฐ์†Œ๊ฐ€ ํฌ ๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ์ด๋Š” H4-1~H4-5์˜ UPV ๊ฐ์†Œ ๊ธฐ์šธ๊ธฐ๊ฐ€ ๊ฐ€์žฅ ๊ฐ€ ํŒŒ๋ฅด๊ณ , ๊ทธ๋‹ค์Œ์ด H6-1~H6-5์˜ UPV์˜ ๊ฐ์†Œ ๊ธฐ์šธ๊ธฐ, ๊ทธ๋ฆฌ๊ณ  H8-1~H8-5์˜ ๊ธฐ์šธ๊ธฐ๊ฐ€ ๊ฐ€์žฅ ์™„๋งŒํ•˜๊ฒŒ ๋‚˜ํƒ€๋‚œ ๊ฒƒ์„ ํ†ตํ•ด ์•Œ ์ˆ˜ ์žˆ๋‹ค. ๋”ฐ๋ผ์„œ OPC์˜ ํ˜ผํ•ฉ๋ฅ ์ด ์ž‘์€ ๋ฐฐํ•ฉ์€ ์ƒ๋Œ€์ ์œผ๋กœ GGBFS-FA ํ˜ผํ•ฉ๋ฅ ์ด ํฐ ๋ฐฐํ•ฉ์ด ๋˜๋ฉฐ, ์ด๋Š” ์ƒ๋Œ€์ ์œผ๋กœ OPC ๋ณด๋‹ค ๋Š๋ฆฐ ์ˆ˜ํ™”๋ฐ˜์‘์œผ๋กœ ์ธํ•ด ์‹œํ—˜์ฒด์˜ ๊ท ์งˆํ•œ ๋ฐ˜์‘์ƒ์„ฑ๋ฌผ์งˆ ์„ ๋งŒ๋“œ๋Š”๋ฐ ์‹œ๊ฐ„์ด ํ•„์š”ํ•˜๊ณ , ๊ทธ๋™์•ˆ ์‹œํ—˜์ฒด ์กฐ์ง์€ 100% OPC ๋ณด๋‹ค ๋‚ฎ์€ UPV๊ฐ€ ์ธก์ •๋œ๋‹ค. ๋˜ํ•œ Berodier and Scrivenet (2015)์˜ ์—ฐ๊ตฌ์—์„œ FA๋ณด๋‹ค GGBFS๊ฐ€ ์‹œํ—˜์ฒด ๋‚ด๋ถ€์˜ ์ด ๊ณต๊ทน ๋ฅ ์„ ๊ฐ์†Œ์‹œํ‚ค๋Š”๋ฐ ๋” ํšจ๊ณผ์ ์ด๋ผ๊ณ  ํ•˜์˜€๋‹ค. ์ด๋Š” GGBFS๊ฐ€ FA๋ณด๋‹ค ๋ฐ˜์‘์„ฑ์ด ๋” ์ข‹์•„์„œ ์‹œํ—˜์ฒด ๋‚ด๋ถ€์˜ ๋ฏธ์„ธ ๊ณต๊ทน์„ ๋น ๋ฅด ๊ฒŒ ์ฑ„์šฐ๋Š” ํšจ๊ณผ ๋•Œ๋ฌธ์ด๋ผ๊ณ  ์–ธ๊ธ‰ํ•˜๊ณ  ์žˆ๋‹ค.

์‹œํ—˜์ฒด ๋‚ด๋ถ€์— ๊ณต๊ทน์ด ๋งŽ์„์ˆ˜๋ก UPV๋Š” ๊ฐ์†Œํ•œ๋‹ค. ๋”ฐ๋ผ์„œ FA๋ณด๋‹ค GGBFS๊ฐ€ ๋งŽ์ด ํ˜ผํ•ฉ๋œ ๋ฐฐํ•ฉ์ผ์ˆ˜๋ก ์ƒ๋Œ€์ ์œผ๋กœ ๋†’์€ UPV๊ฐ’์„ ๋‚˜ํƒ€๋‚ธ๋‹ค. ลžahmaran et al.(2008)์€ OPC-FA ์‹œํ—˜์ฒด ์—์„œ FA๋ฅผ 0%, 35% ๊ทธ๋ฆฌ๊ณ  55%๋กœ ์น˜ํ™˜ํ•œ ๋Œ€๋Ÿ‰์น˜ํ™˜ ํ”Œ๋ผ์ด ์• ์‹œ ์ฝ˜ํฌ๋ฆฌํŠธ(HVFA-SCC)์—์„œ ๋‹ด์ˆ˜์— ์นจ์ง€ํ•œ ์ž๊ธฐ์น˜์œ  ์‹œ ํ—˜์ฒด์˜ UPV๋Š” FA ์น˜ํ™˜์œจ์ด ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ ๊ฐ์†Œํ•˜๋Š” ๊ฒฐ๊ณผ๋ฅผ ์–ธ๊ธ‰ํ•˜์˜€๋‹ค.

ํŠนํžˆ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด์— ๋Œ€ํ•œ UPV ์ธก์ • ๊ฒฐ๊ณผ์—์„œ (Fig. 2(b), (d)), ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ํ›„ UPV ๊ฐ’(UPVCRK)์€ OPC ๋ณด๋‹ค ๊ฐ์†Œ์ •๋„๊ฐ€ ์ƒ๋Œ€์ ์œผ๋กœ ํฌ๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ์ด๋Š” ๊ท ์—ด๋ฉด์— ๋ถ„ํฌ์— ์žˆ๋Š” ๋ฏธ์ˆ˜ํ™” GGBFS์™€ FA๋กœ ์ธํ•ด UPV๊ฐ€ ๊ฐ์†Œํ•œ ๊ฒƒ ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ Fig. 2์˜ UPV๋Š” ๋‹จ์ˆœํ•œ ์ธก์ •๊ฐ’์„ ๋‚˜ํƒ€ ๋‚ธ ๊ฒƒ์œผ๋กœ ์ƒ๋Œ€์ ์ธ ๋น„๊ต์— ์–ด๋ ค์›€์ด ์žˆ์–ด์„œ ๋ณด๋‹ค ๋ช…ํ™•ํ•œ UPV ๊ฐ’์˜ ๋น„๊ต๋ฅผ ์œ„ํ•ด UPV ์ฆ๊ฐ€์œจ์„ ํ†ตํ•ด ๋น„๊ต ๋ถ„์„์„ ํ•˜์˜€๋‹ค.

Fig. 3์€ UPV ์ธก์ • ์‹œ์ ๊ฐ„ ์ƒ๋Œ€์ ์ธ UPV ์ฆ๊ฐ€์œจ์„ ๋‚˜ํƒ€๋‚ธ ๊ฒƒ์ด๋‹ค. ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด์— ๋Œ€ํ•ด ฮ”UPVINT-30 ์€(์‹ 1)) ์ดˆ๊ธฐ UPV ์ธก์ •๊ฐ’ (UPVINT)์— ๋Œ€ํ•œ ์นจ์ง€ 30์ผ์—์„œ ์˜ ์ธก์ •๊ฐ’(UPV30)๊ณผ์˜ ์ƒ๋Œ€์  ์ฆ๊ฐ€์œจ์ด๋ฉฐ, ฮ”UPV30-60์€(์‹ (2)) ์นจ์ง€ 30์ผ์—์„œ์˜ UPV ์ธก์ •๊ฐ’(UPV30)์— ๋Œ€ํ•œ ์นจ์ง€ 60์ผ ์ธก์ •๊ฐ’(UPV60)์˜ ์ƒ๋Œ€์  ๋น„์œจ์ด๋‹ค. ๋˜ํ•œ ์‹ (3)์€ ๊ท ์—ด์„ ๋ฐœ ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด์˜ ๊ท ์—ด๋ฐœ์ƒ์‹œ ์ธก์ •ํ•œ UPV์— ๋Œ€ํ•œ ์นจ์ง€ 30์ผ์— ์„œ์˜ UPV ๊ฐ’์˜ ์ƒ๋Œ€์  ์ฆ๊ฐ€์œจ(ฮ”UPVCRK-30)์ด๊ณ  ์นจ์ง€ 30์ผ ์—์„œ์˜ UPV ์ธก์ •๊ฐ’(UPV30)์— ๋Œ€ํ•œ ์นจ์ง€ 60์ผ ์ธก์ •๊ฐ’(UPV60) ์˜ ์ƒ๋Œ€์  ๋น„์œจ์€ ์‹ (1)์ด๋‹ค. ์ด๋ฅผ ํ†ตํ•ด ์นจ์ง€ 30์ผ ๋™์•ˆ ์ฆ๊ฐ€ ํ•œ UPV์™€ ์นจ์ง€ 30์ผ์—์„œ 60์ผ๊นŒ์ง€์˜ UPV ์ฆ๊ฐ€์œจ์„ ํ™•์ธํ•  ์ˆ˜ ์žˆ๋‹ค.

Fig. 3

The rate of increase in UPV

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(1)
ฮ” U P V I N T โˆ’ 30 = U P V 30 โˆ’ U P V I N T U P V I N T ร— 100

(2)
ฮ” U P V 30 โˆ’ 60 = U P V 60 โˆ’ U P V 30 U P V 30 ร— 100

(3)
ฮ” U P V C R K โˆ’ 30 = U P V 30 โˆ’ U P V C R K U P V C R K ร— 100

๋˜ํ•œ ์‹ (1)~(3)์— ์˜ํ•ด ์นจ์ง€ ํ›„ 30์ผ๊ณผ 30์ผ๋ถ€ํ„ฐ 60์ผ๊นŒ์ง€ ์˜ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด์˜ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ์™€ ๊ท ์—ด์„ ๋ฐœ์ƒ ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด์˜ ๋‹จ์ˆœ ์žฌ๋ น ์ฆ๊ฐ€์— ๋”ฐ๋ฅธ UPV๊ฐ’์˜ ์ƒ๋Œ€ ์  ์ฆ๊ฐ€์œจ์„ ๊ณ„์‚ฐํ•˜์—ฌ ๋น„๊ตํ•˜์˜€๋‹ค. ๊ฐ๊ฐ์˜ ๊ณ„์‚ฐ๋œ ๊ฒฐ๊ณผ๋ฅผ ๊ทธ ๋ž˜ํ”„๋กœ ๋‚˜ํƒ€๋‚ธ ๊ฒƒ์ด Fig. 3์ด๋‹ค.

๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด(Fig. 3(a), (c))์™€ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด(Fig. 3(b), (d))์˜ ์ƒ๋Œ€์  UPV ์ฆ๊ฐ€์œจ์„ ๋‚˜ํƒ€๋‚ด์—ˆ๋‹ค. 100% OPC์™€ ๋ชจ๋“  TBC ๋ฐฐํ•ฉ์— ์„œ ์นจ์ง€ ํ›„ 30์ผ๊นŒ์ง€์˜ UPV์ฆ๊ฐ€์œจ(ฮ”UPVINT-30, ฮ”UPVCRK-30) ์ด 30์ผ๋ถ€ํ„ฐ 60์ผ๊นŒ์ง€์˜ UPV ์ฆ๊ฐ€์œจ(ฮ”UPV30-60)๋ณด๋‹ค ํฌ๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ์ด๋Š” ์นจ์ง€ ํ›„ ์ดˆ๊ธฐ 30์ผ๊นŒ์ง€ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š ์€ ์‹œํ—˜์ฒด๋Š” ์žฌ๋ น์— ์˜ํ•œ UPV ์ฆ๊ฐ€ ํšจ๊ณผ๊ฐ€, ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด์˜ ๊ฒฝ์šฐ๋Š” ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ์— ์˜ํ•œ UPV ์ฆ๊ฐ€๊ฐ€ ๊ฐ€์žฅ ํ™œ ๋ฐœํ•˜๊ฒŒ ์ผ์–ด๋‚˜๊ณ  ์žˆ๋‹ค๋Š” ๊ฒƒ์„ ๋‚˜ํƒ€๋‚ธ๋‹ค. ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œ ํ—˜์ฒด์˜ UPV ์ฆ๊ฐ€์œจ์€ Huand et al.(2013)๊ณผ In et al.(2013)์˜ ์—ฐ๊ตฌ์—์„œ๋„ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋Š” ์นจ์ง€ ์ดˆ๊ธฐ ๋˜๋Š” ์นจ์ง€ ํ›„ 30์ผ ์ „ ํ›„๋กœ ๊ฐ€์žฅ ํ™œ๋ฐœํžˆ ์ผ์–ด๋‚œ๋‹ค๋Š” ๊ฒฐ๊ณผ์™€ ์œ ์‚ฌํ•˜๋‹ค.

๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด์˜ ๊ฒฝ์šฐ ฮ”UPVCRK-30์ด ๊ท ์—ด์„ ๋ฐœ ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด์˜ ๊ฐ’ ฮ”UPVINT-30๋ณด๋‹ค ํฌ๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด(Fig. 3(a), (c))์™€ ๊ท ์—ด์„ ๋ฐœ์ƒ ์‹œํ‚จ ์‹œํ—˜์ฒด(Fig. 3(b), (d)) ๋ชจ๋‘ ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜ ์นจ์ง€ ๊ฒฐ๊ณผ์—์„œ, ๋™์ผํ•œ OPC ํ˜ผํ•ฉ๋ฅ ์—์„œ GGBFS-FA ํ˜ผํ•ฉ๋ฅ ์— ๋”ฐ๋ฅธ UPV ๊ฐ ์†Œ ํŠน์„ฑ์€ GGBFS ์น˜ํ™˜์œจ์ด ๊ฐ์†Œํ•จ์— ๋”ฐ๋ผ ฮ”UPVINT-30์™€ ฮ”UPVCRK-30๊ฐ€ ๊ฐ์†Œํ•˜๊ณ  ์žˆ๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜ ์ฒด์˜ ๊ฒฝ์šฐ๊ฐ€(Fig. 3(b), (d)) ๋™์ผํ•œ OPC ํ˜ผํ•ฉ๋ฅ ์„ ๊ฐ€์ง€๋Š” ์‹œํ—˜ ์ฒด์—์„œ GGBFS ์น˜ํ™˜์œจ์ด ๊ฐ์†Œํ•จ์— ๋”ฐ๋ผ ฮ”UPVCRK-30๊ฐ€ ๊ฐ ์†Œํ•˜๋Š” ๊ธฐ์šธ๊ธฐ๊ฐ€ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด(Fig. 3(a), (c))์™€ ๋น„๊ตํ•˜์—ฌ ์ƒ๋Œ€์ ์œผ๋กœ ์™„๋งŒํ•˜๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ์ด๋Š” ๊ท ์—ด๋ฉด ์— ๋…ธ์ถœ๋œ GGBFS์™€ FA๊ฐ€ OPC๋ณด๋‹ค ๋Š๋ฆฐ ์ˆ˜ํ™”๋ฐ˜์‘์œผ๋กœ ์ธํ•ด ๊ธ‰๊ฒฉํ•œ UPV์˜ ๋ณ€ํ™”๋ณด๋‹ค ์ƒ๋Œ€์ ์œผ๋กœ ์™„๋งŒํ•œ ๋ณ€ํ™”๋ฅผ ๋‚˜ํƒ€๋‚ด๋Š” ๊ฒƒ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค.

๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด ๋ชจ๋‘ ฮ”UPV30-60๋Š” OPC์˜ ํ˜ผํ•ฉ๋ฅ ์ด ๋‚ฎ์•„์งˆ์ˆ˜๋ก GGBFS-FA์˜ ํ˜ผํ•ฉ๋ฅ ์— ๋”ฐ๋ผ ์™„๋งŒํ•˜๊ฒŒ ์ฆ๊ฐ€ํ•˜๊ณ  ์žˆ๋‹ค. Fig. 3(a)์—์„œ H8-1์—์„œ H8-5๊นŒ์ง€ GGBFS์˜ ์น˜ํ™˜์œจ์ด ๊ฐ์†Œํ•จ์— ๋”ฐ๋ผ ์™„๋งŒํ•œ ๊ธฐ์šธ๊ธฐ๋กœ ฮ”UPV30-60๊ฐ€ ์ฆ๊ฐ€ ํ•˜๊ณ  ์žˆ๋‹ค. H6 series์™€ H4 series๋„ ์ด์™€ ์œ ์‚ฌํ•˜๊ฒŒ GGBFS์˜ ์น˜ํ™˜์œจ์ด ๊ฐ์†Œํ•จ์— ๋”ฐ๋ผ ฮ”UPV30-60๊ฐ€ ์™„๋งŒํ•˜๊ฒŒ ์ฆ๊ฐ€ํ•˜๊ณ  ์žˆ ๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด๋“ค์€(Fig. 3(c)) H8๊ณผ H6์€ ๋‹ด์ˆ˜์™€ ์œ ์‚ฌํ•˜๊ฒŒ ์ฆ๊ฐ€ํ•˜๋Š” ๊ฒฝํ–ฅ์„ ๋‚˜ํƒ€๋ƒˆ์ง€๋งŒ, H4๋Š” GGBFS ์น˜ํ™˜์œจ์ด ๊ฐ์†Œํ•จ์— ๋”ฐ๋ผ ์™„๋งŒํ•˜๊ฒŒ ๊ฐ์†Œํ•˜๊ณ  ์žˆ์—ˆ๋‹ค. ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด์— ๋Œ€ํ•œ ฮ”UPV30-60๋„ ๋น„์Šทํ•œ ๊ฒฝํ–ฅ์„ ๋ณด์ธ๋‹ค (Fig. 3(b), (d)). ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด๋Š” ์ฐธ์ˆ˜์™€ ํ•ด์ˆ˜์— ์นจ ์ง€ํ•œ ๊ฒฝ์šฐ ๋ชจ๋‘ H4 series > H6 series > H8 series ์ˆœ์„œ๋กœ ฮ”UPV30-60๊ฐ€ ๊ฐ์†Œํ•˜๊ณ  ์žˆ๋‹ค. ์ด๋Š” ๊ฒฐํ•ฉ์žฌ๋ฅผ ๊ตฌ์„ฑํ•˜๊ณ  ์žˆ๋Š” ์žฌ๋ฃŒ ์ค‘ GGBFS-FA์˜ ํ˜ผํ•ฉ๋ฅ ์ด ๋†’์„์ˆ˜๋ก(OPC ํ˜ผํ•ฉ๋ฅ ์ด ๋‚ฎ ์„์ˆ˜๋ก) ๋ฏธ์ˆ˜ํ™” ์ž…์ž์˜ ์žฌ์ˆ˜ํ™” ๋“ฑ์„ ํ†ตํ•ด ์ ์ฐจ UPV๊ฐ€ ์ฆ๊ฐ€ํ•˜ ๋Š”๋ฐ ๊ธฐ์—ฌํ•˜๊ธฐ ๋•Œ๋ฌธ์œผ๋กœ ์ƒ๊ฐ๋œ๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ๊ท  ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด์™€ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด์—์„œ H4๋Š” ฮ”UPV30-60์ด ์™„๋งŒํ•˜๊ฒŒ ๊ฐ์†Œํ•˜๋Š” ๊ฒƒ์— ๋Œ€ํ•œ ์›์ธ์€ ์•„ ์ง๊นŒ์ง€ ๋ช…ํ™•ํ•˜์ง€ ์•Š๋‹ค. ๋‹ค๋ฅธ ๋ฐฐํ•ฉ์— ๋น„ํ•ด ์ƒ๋Œ€์ ์œผ๋กœ OPC๋ณด ๋‹ค ์ƒ๋‹นํžˆ ๋†’์€ GGBFS-FA ๋ฐฐํ•ฉ๋ฅ (60%)์€ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ๋‚˜ํƒ€๋‚ด๊ธฐ ์œ„ํ•ด GGBFS ๋˜๋Š” FA๊ฐ€ ์ถฉ๋ถ„ํžˆ ์ˆ˜ํ™”๋  ์ˆ˜ ์žˆ๋Š” ํ™˜ ๊ฒฝ์„ ์กฐ์„ฑํ•˜๋Š”๋ฐ ๊ธด ์‹œ๊ฐ„์ด ํ•„์š”ํ•  ๊ฒƒ์œผ๋กœ ์ƒ๊ฐ๋œ๋‹ค. ๋ณธ ์—ฐ๊ตฌ ์˜ ๊ฒฐ๊ณผ๋ฅผ ๋ณผ ๋•Œ ๋‹ด์ˆ˜์™€ ๋‹ฌ๋ฆฌ ํ•ด์ˆ˜์—์„œ๋Š” ๋‹ค๋ฅธ ํ˜ผํ™”์žฌ๋ฃŒ์™€ ๋น„ ๊ตํ•˜์—ฌ ์ƒ๋Œ€์ ์œผ๋กœ FA์˜ ์น˜ํ™˜์œจ์ด ์ฆ๊ฐ€ํ•  ๋•Œ UPV ์ฆ๊ฐ€์œจ์„ ๋‚ฎ์•„์ง€๋Š” ๊ฒƒ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค. ์ด๋Ÿฌํ•œ ๊ฒฝํ–ฅ์€ ํŠนํžˆ ์นจ์ง€ 30์ผ์— ์„œ ์ธก์ •ํ•œ UPV ์ฆ๊ฐ€์œจ(ฮ”UPVINT-30, ฮ”UPVCRK-30)์—์„œ ํ™• ์—ฐํžˆ ๋‚˜ํƒ€๋‚œ๋‹ค. ์ด๋Š” GGBFS์™€ FA๋ฅผ ๋น„๊ตํ•  ๋•Œ ์ƒ๋Œ€์ ์œผ๋กœ GGBFS ๋ณด๋‹ค ๋Š๋ฆฐ ์ˆ˜ํ™”๋ฐ˜์‘์„ฑ์„ ๊ฐ€์ง„ FA์˜ ์˜ํ–ฅ์œผ๋กœ ์ƒ๊ฐํ•  ์ˆ˜ ์žˆ๋‹ค.

Fig. 3์˜ UPV ์ฆ๊ฐ€์œจ์˜ ๊ฒฐ๊ณผ๋ฅผ ๋น„๊ตํ•˜์—ฌ ๋ณผ ๋•Œ GGBFS-FA ํ˜ผํ•ฉ๋ฅ ์— ๋”ฐ๋ผ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๊ฐ€ ์ผ์ • ์นจ์ง€์‹œ๊ธฐ์™€ ๋ฐฐํ•ฉ์—์„œ ํ–ฅ์ƒ๋˜๋Š” ๊ฒƒ์„ ํ™•์ธํ•  ์ˆ˜ ์žˆ์—ˆ๋‹ค. ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ ๊ฒ€ํ† ๋ฅผ ์œ„ํ•ด GGBFS์™€ FA๋ฅผ ์‚ฌ์šฉํ•œ ์„ ํ–‰์—ฐ๊ตฌ์—์„œ๋„ ์œ ์‚ฌํ•œ ๊ฒฐ๊ณผ๊ฐ€ ๋‚˜ํƒ€ ๋‚ฌ๋‹ค(Liu and Zuo, 2011). ํŠนํžˆ GGBFS๊ฐ€ FA์™€ ๋น„๊ตํ•˜์—ฌ ์ƒ๋Œ€ ์ ์œผ๋กœ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ์ฆ๊ฐ€์‹œํ‚ค๋Š”๋ฐ ๊ธ์ •์ ์ธ ์—ญํ• ์„ ํ•˜๋Š” ๊ฒƒ์œผ๋กœ ๋‚˜ํƒ€๋‚ฌ๋‹ค. GGBFS์˜ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ ํ–ฅ์ƒ์€ Tittelboom et al.(2012)์˜ ์—ฐ๊ตฌ๊ฒฐ๊ณผ์—์„œ๋„ ํ™•์ธํ•  ์ˆ˜ ์žˆ๋Š”๋ฐ, ๋ณธ ์—ฐ๊ตฌ์—์„œ ๋„ Fig. 3์—์„œ ๋‚˜ํƒ€๋‚˜๋“ฏ GGBFS๋ฅผ ํ˜ผํ•ฉํ•œ ์‹œํ—˜์ฒด์˜ UPV ์ฆ๊ฐ€ ์œจ์ด 100% OPC ๋ณด๋‹ค ํ–ฅ์ƒ๋œ ๊ฒฐ๊ณผ๊ฐ€ ๋‚˜ํƒ€๋‚ฌ๋‹ค.

Fig. 4๋Š” UPV ์ธก์ •์„ ํ†ตํ•ด ๊ท ์—ด์ด ๋ฐœ์ƒํ•œ ์‹œํ—˜์ฒด์˜ ์ž๊ธฐ์น˜ ์œ  ํšจ๊ณผ์™€ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด์˜ ์žฌ๋ น์˜ ์˜ํ–ฅ์„ ๋™์ผ ๋ฐฐํ•ฉ์˜ ์‹œํ—˜์ฒด์— ๋Œ€ํ•ด ๊ณ„์‚ฐํ•˜์˜€๋‹ค. ์ด๋ฅผ ํ†ตํ•ด ์žฌ๋ นํšจ๊ณผ ๋ฅผ ๊ณ ๋ คํ•œ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ์‚ดํŽด๋ณด๊ณ ์ž ํ•˜์˜€๋‹ค. ์ผ๋ฐ˜์ ์œผ๋กœ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด(uncracked specimens)์˜ UPV๋Š” ๋‚ด๋ถ€ ๊ณต๊ทน์ด๋‚˜ ๋ฐ€๋„(density)๋“ฑ์— ์˜ํ–ฅ์„ ๋ฐ›๊ณ . ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด(cracked specimens)์˜ UPV๋Š” ๊ท ์—ด์˜ ์˜ํ–ฅ ๊นŒ์ง€ ์ถ”๊ฐ€์ ์œผ๋กœ ๊ณ ๋ คํ•ด์•ผ ํ•œ๋‹ค. ๋”ฐ๋ผ์„œ ๋™์ผ ๋ฐฐํ•ฉ์˜ ์‹œํ—˜์ฒด ์—๋Œ€ํ•ด ๋™์ผํ•œ ์žฌ๋ น์—์„œ ์ธก์ •ํ•œ UPV์˜ ์ฐจ์ด๋ฅผ ํ†ตํ•ด ๋‹จ์ˆœํ•œ ์žฌ๋ น์— ์˜ํ•œ UPV ๋ณ€ํ™”์™€ ์ž๊ธฐ์น˜์œ ์— ์˜ํ•œ ๋ณ€ํ™”๋ฅผ ๊ณ„์‚ฐํ•˜์—ฌ ์žฌ๋ น ํšจ๊ณผ๋ฅผ ๊ณ ๋ คํ•œ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ๊ฒ€ํ† ํ•  ์ˆ˜ ์žˆ์„ ๊ฒƒ์œผ๋กœ ์ƒ๊ฐํ•˜์˜€๋‹ค.

Fig. 4

The effect of self-healing and age

JKSMI-20-10_F4.jpg

์‹ (4)๋Š” ๋™์ผํ•œ ๋ฐฐํ•ฉ์˜ ์‹œํ—˜์ฒด์— ๋Œ€ํ•ด ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œ ํ—˜์ฒด์˜ ์นจ์ง€ 30์ผ๊นŒ์ง€์˜ UPV ์ฆ๊ฐ€๋Ÿ‰(cracked ฮ”UPVCRK-30) ์—์„œ ์นจ์ง€ 30์ผ์—์„œ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด์˜ UPV ์ฆ๊ฐ€๋Ÿ‰(uncracked ฮ”UPVINT-30)์˜ ์ฐจ์ด๋‹ค. ์‹ (5)๋Š” ์นจ์ง€ 30 ์ผ์—์„œ 60์ผ๊นŒ์ง€์˜ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด์˜ UPV ์ฆ๊ฐ€์œจ (cracked ฮ”UPV30-60)๊ณผ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด์˜ UPV ์ฆ๊ฐ€์œจ(uncracked ฮ”UPV30-60)์˜ ์ฐจ์ด๋‹ค. ฮ”UPV30 ๊ณผ UPV60์˜ ์œ—์ฒจ์ž TE๋Š” ๋‹ด์ˆ˜์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด๋ฅผ ์˜๋ฏธํ•˜๊ณ , SE๋Š” ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด์— ๋Œ€ํ•œ UPV ๊ณ„์‚ฐ ๊ฐ’์„ ์˜๋ฏธํ•œ๋‹ค (Fig. 4 ์ฐธ์กฐ).

(4)
ฮ” U P V 30 = crackedโ€‰ ฮ” U P V C R K โˆ’ 30 โˆ’ uncrackedโ€‰ ฮ” U P V I N T โˆ’ 30

(5)
ฮ” U P V 60 = crackedโ€‰ ฮ” U P V 30 โˆ’ 60 โˆ’ uncrackedโ€‰ ฮ” U P V 30 โˆ’ 60

์‹ (4)์™€ ์‹ (5)์˜ ๊ณ„์‚ฐ๊ฒฐ๊ณผ์—์„œ ์Œ์ˆ˜(-)์˜ ์˜๋ฏธ๋Š” UPV ์ฆ๊ฐ€ ์— ์˜ํ–ฅ์„ ์ค€ ์ฃผ์š” ์›์ธ์€ ์ž๊ธฐ์น˜์œ ์— ์˜ํ•œ ํšจ๊ณผ๋ณด๋‹ค ์ƒ๋Œ€์  ์œผ๋กœ ์žฌ๋ น์— ์˜ํ•œ ํšจ๊ณผ๊ฐ€ ๋” ํฐ ์˜ํ–ฅ์„ ๋ฏธ์ณค๋‹ค๋Š” ์˜๋ฏธ์ด๋‹ค.

Fig. 4๋ฅผ ๋ณด๋ฉด, ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด ๋ชจ๋‘ ์นจ์ง€ 30 ์ผ์— ์ธก์ •ํ•œ UPV ๊ฐ’์˜ ๋ณ€ํ™”๋Š” 0์ด์ƒ์˜ ๊ฐ’์œผ๋กœ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ์ด ๋Š” ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด๋ฅผ ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ์นจ์ง€ํ•  ๊ฒฝ์šฐ ์นจ ์ง€ 30์ผ๊นŒ์ง€๋Š” ์žฌ๋ น์˜ ์ฆ๊ฐ€์— ๋”ฐ๋ฅธ UPV ์ฆ๊ฐ€๋ณด๋‹ค ์ž๊ธฐ์น˜์œ  ์— ์˜ํ•œ UPV ์ฆ๊ฐ€๊ฐ€ ๋”์šฑ ํฌ๊ฒŒ ์ž‘์šฉํ•˜๋Š” ๊ฒƒ์„ ์˜๋ฏธํ•œ๋‹ค (Huand et al., 2013; In et al., 2013). ๊ทธ๋Ÿฌ๋‚˜ ์นจ์ง€ 30์ผ๋ถ€ํ„ฐ 60 ์ผ๊นŒ์ง€๋Š” ์Œ์ˆ˜ ๋˜๋Š” 0์— ๊ทผ์‚ฌํ•œ ๊ฐ’(โ‰ค1.0)์„ ๋‚˜ํƒ€๋‚ด๊ณ  ์žˆ์–ด ์ž ๊ธฐ์น˜์œ  ํšจ๊ณผ๊ฐ€ ์žฌ๋ นํšจ๊ณผ์™€ ๋น„๊ตํ•˜์—ฌ ๊ธ‰๊ฒฉํžˆ ๊ฐ์†Œํ–ˆ๊ฑฐ๋‚˜, ์ž ๊ธฐ์น˜์œ ํšจ๊ณผ์™€ ์žฌ๋ นํšจ๊ณผ๊ฐ€ ๋ชจ๋‘ ๋ฏธ๋ฏธํ•˜์—ฌ ๊ทผ์†Œํ•œ ์ฐจ์ด๋กœ UPV ๊ฐ’์˜ ์ฆ๊ฐ€์— ์˜ํ–ฅ์„ ์ค€๋‹ค๋Š” ์˜๋ฏธ์ด๋‹ค. ๋˜ํ•œ OPC๊ฐ€ 80%(H8 series)์—์„œ 40%(H4 series)๋กœ ๊ฐ์†Œํ• ์ˆ˜๋ก ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด ๋ชจ๋‘ ฮ” U P V 30 T E ์™€ ฮ” U P V 30 S E ๊ฐ€ ์ ์ฐจ ๊ฐ์†Œํ•˜์—ฌ ฮ” U P V 60 T E ์™€ ฮ” U P V 60 S E ์— ์ ์ฐจ ๊ฐ€๊นŒ์›Œ์ง€๊ณ  ์žˆ๋‹ค. ์ด๋Š” OPC์˜ ํ˜ผํ•ฉ๋ฅ ์ด ๊ฐ์†Œํ•จ์— ๋”ฐ๋ผ ์ƒ๋Œ€์ ์œผ๋กœ GGBFS-FA์˜ ํ˜ผํ•ฉ๋ฅ ์ด ์ฆ๊ฐ€ํ•˜๊ณ  ๊ทธ์— ๋”ฐ๋ผ ์ˆ˜ํ™”๋ฐ˜์‘์˜ ์ง€์—ฐ๊ณผ ๋ฏธ์ˆ˜ํ™” ์ž…์ž์˜ ์ฆ๊ฐ€ ๋•Œ๋ฌธ์— ์žฌ ๋ น์˜ ์ฆ๊ฐ€์— ๋”ฐ๋ฅธ UPV ์ฆ๊ฐ€ํšจ๊ณผ๊ฐ€ ์ž๊ธฐ์น˜์œ ํšจ๊ณผ ๋ณด๋‹ค ์ปค์กŒ ๊ฑฐ๋‚˜ ์žฌ๋ น๊ณผ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ ๋ชจ๋‘ ์ถฉ๋ถ„ํžˆ ๋‚˜ํƒ€๋‚˜์ง€ ์•Š์•˜๊ธฐ ๋•Œ ๋ฌธ์œผ๋กœ ์ƒ๊ฐ๋œ๋‹ค. ๋”ฐ๋ผ์„œ GGBFS-FA์˜ ํ˜ผํ•ฉ๋ฅ ์ด ์ฆ๊ฐ€ํ•˜๋Š” ๋ฐฐํ•ฉ์˜ ๊ฒฝ์šฐ์—๋Š” ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ์™€ ์žฌ๋ น์˜ ์ฆ๊ฐ€์— ๋”ฐ๋ฅธ UPV ํ–ฅ์ƒ์— ํ•จ๊ป˜ ์˜ํ–ฅ์„ ๋ฏธ์น˜์ง€๋งŒ, ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๊ฐ€ ์žฌ๋ นํšจ๊ณผ๋ณด ๋‹ค ์ปค์ง€๋Š” ๊ฒƒ์„ ํ™•์—ฐํžˆ ๊ด€์ฐฐํ•  ๋•Œ ๊นŒ์ง€๋Š” ์นจ์ง€ 60์ผ ์ด์ƒ์˜ ์žฅ ๊ธฐ๊ฐ„์˜ ์นจ์ง€๊ฐ€ ํ•„์š”ํ•  ๊ฒƒ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค.

Fig. 4์—์„œ ๋ณด๋ฉด, OPC๋ฅผ ๋น„๋กฏํ•œ ๋Œ€๋ถ€๋ถ„์˜ ์‹œํ—˜์ฒด์—์„œ ๋‹ด์ˆ˜ ๋ณด๋‹ค ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ์‹œํ—˜์ฒด์˜ ์นจ์ง€ 30์ผ์—์„œ์˜ ์ž๊ธฐ์น˜์œ ํšจ๊ณผ ๊ฐ€ ๋‹ด์ˆ˜๋ณด๋‹ค ๋†’๊ฒŒ ๋‚˜ํƒ€๋‚˜๊ณ  ์žˆ๋‹ค. ์ด๋Š” ํ•ด์ˆ˜์— ํฌํ•จ๋œ ์—ฌ๋Ÿฌ ๋ฌด ๊ธฐ๋ฌผ์งˆ ์ค‘ ์ผ๋ถ€๊ฐ€ ๊ท ์—ด์˜ ์ž๊ธฐ์น˜์œ  ๋˜๋Š” ๊ท ์—ด๋ฉด ์‚ฌ์ด์˜ ๊ณต๊ฐ„ ์„ ์ค„์ด๋Š”๋ฐ ์ผ๋ถ€ ๊ธฐ์—ฌํ•˜๋Š” ๊ธ์ •์ ์ธ ์—ญํ• ์„ ํ•˜๊ธฐ ๋•Œ๋ฌธ์œผ๋กœ ์ƒ๊ฐํ•  ์ˆ˜ ์žˆ๋‹ค. Palin et al.(2015)์˜ ์—ฐ๊ตฌ์—์„œ๋„ ํ•ด์ˆ˜์— ์นจ์ง€ ํ•œ ์‹œํ—˜์ฒด์˜ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๊ฐ€ ๋‹ด์ˆ˜๋ณด๋‹ค ๋น ๋ฅด๋ฉฐ, ์ด์œ ๋Š” ํ•ด์ˆ˜ ์— ํฌํ•จ๋œ ๋‹ค์–‘ํ•œ ์ด์˜จ๋“ค์˜ ํšจ๊ณผ ๋•Œ๋ฌธ์ด๋ผ๊ณ  ํ•˜์˜€๋‹ค.

๋ณธ ์—ฐ๊ตฌ๋Š” ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ์นจ์ง€๋œ TBC์˜ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ UPV๋ฅผ ์‚ฌ์šฉํ•˜์—ฌ ์ธก์ •ํ•˜๋Š” ๊ฒƒ์œผ๋กœ์จ, ํ•ด์ˆ˜์— ํฌํ•จ๋œ ๋‹ค์–‘ํ•œ ์ด์˜จ๋“ค์ด ์ž๊ธฐ์น˜์œ ์— ์–ด๋–ค ํšจ๊ณผ์™€ ์ž‘์šฉ์„ ํ•˜๋Š”์ง€, ๊ทธ ๋ฉ”์ปค๋‹ˆ ์ฆ˜์— ๋Œ€ํ•œ ์—ฐ๊ตฌ๋Š” ํ›„์†์—ฐ๊ตฌ๊ฐ€ ํ•„์š”ํ•˜๋‹ค.

Fig. 5๋Š” ์‹œํ—˜์ฒด๋“ค์˜ SEM ์ด๋ฏธ์ง€์ด๋‹ค. H8, H6 ๊ทธ๋ฆฌ๊ณ  H4 ๋ชจ๋‘ GGBFS์™€ FA ํ˜ผํ•ฉ๋ฅ ์— ๊ด€๊ณ„์—†์ด ๊ท ์—ด๋ถ€์—์„œ ๊ด€์ฐฐ๋˜๋Š” ๋ฐ˜์‘์ƒ์„ฑ๋ฌผ์งˆ์€ ๊ฑฐ์˜ ์œ ์‚ฌํ•˜์˜€๋‹ค. ๋Œ€์ฒด์ ์œผ๋กœ ๋ฏธ์ˆ˜ํ™” ์ž…์ž๋“ค์— ์˜ํ•œ ์žฌ์ˆ˜ํ™”(re-hydration)์— ์˜ํ•œ ๋ฐ˜์‘์ƒ์„ฑ๋ฌผ์งˆ์˜ ํ•˜๋‚˜์ธ ettringite ๋˜๋Š” CSH ๋“ฑ์œผ๋กœ ์ถ”์ •๋˜๋Š” ๋ฌผ์งˆ์„ ๊ด€์ฐฐ ํ•  ์ˆ˜ ์žˆ์—ˆ๋‹ค. ๋˜ํ•œ Fig. 5(e)์—์„œ์ฒ˜๋Ÿผ CaCO3์™€ ๊ฐ™์€ ๋ฐ˜์‘ ์ƒ์„ฑ๋ฌผ์งˆ๋„ ๊ด€์ฐฐํ•  ์ˆ˜ ์žˆ์—ˆ๋‹ค. ๊ท ์—ด๋ฉด์—์„œ ๊ด€์ฐฐ๋˜๋Š” ์ƒ์„ฑ๋ฌผ์งˆ์€ ๊ธฐ์กด์˜ ์„ ํ–‰ ์ž๊ธฐ ์น˜์œ  ์—ฐ๊ตฌ๊ฒฐ๊ณผ๋“ค๊ณผ ์œ ์‚ฌํ•˜์˜€๋‹ค(Sahmaran et al., 2013). ํ•ด์ˆ˜ (SW)์—์„œ๋Š” Na์™€ Mg๊ฐ€ ๋‹ด์ˆ˜(TW)๋ณด๋‹ค ๋‹ค์†Œ ํฌ๊ฒŒ ๊ฒ€์ถœ๋˜๊ณ  ์žˆ์–ด ์ผ๋ถ€ ํ•ด์ˆ˜์˜ ์„ฑ๋ถ„์ด ๊ท ์—ด ํ‘œ๋ฉด์—์„œ ์ž๊ธฐ์น˜์œ ์— ์ผ๋ถ€ ์˜ ํ–ฅ์„ ๋ฏธ์น˜๋Š” ๊ฒƒ์œผ๋กœ ์ƒ๊ฐ๋œ๋‹ค.

Fig. 5

SEM images of crack

JKSMI-20-10_F5.jpg

4. ๊ฒฐ ๋ก 

OPC, GGBFS ๊ทธ๋ฆฌ๊ณ  FA๋ฅผ ํ˜ผํ•ฉํ•œ ์‚ผ์„ฑ๋ถ„๊ณ„ ์‹œ๋ฉ˜ํŠธ(TBC) ์˜ ๋‹ด์ˆ˜(tap-water)์™€ ํ•ด์ˆ˜(sea-water)์— ๋…ธ์ถœ๋œ ํ™˜๊ฒฝ์—์„œ UPV ์ธก์ •์„ ํ†ตํ•œ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ์™€ ์žฌ๋ นํšจ๊ณผ๋ฅผ ๊ณ ๋ คํ•œ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ์— ๋Œ€ํ•œ ์—ฐ๊ตฌ๊ฒฐ๊ณผ ๋‹ค์Œ๊ณผ ๊ฐ™์€ ๊ฒฐ๋ก ์„ ์–ป์—ˆ๋‹ค.

  • 1) OPC-GGBFS-FA์˜ ์‚ผ์„ฑ๋ถ„๊ณ„ ์‹œํ—˜์ฒด์—์„œ OPC์˜ ํ˜ผํ•ฉ๋ฅ  ์ด ๊ฐ์†Œํ•จ์— ๋”ฐ๋ผ(GGBFS-FA ํ˜ผํ•ฉ๋ฅ ์ด ์ฆ๊ฐ€ํ•จ์— ๋”ฐ๋ผ) UPV ์ฆ๊ฐ€์œจ(ฮ”UPV)์ด ์ฆ๊ฐ€ํ•˜๊ณ  ์žˆ์—ˆ๋‹ค. ์ด๋Š” GGBFS-FA ๋“ฑ์˜ ํ˜ผํ™”์žฌ๋ฃŒ๊ฐ€ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ํ–ฅ์ƒ์‹œํ‚ค๋Š” ๊ฒƒ์œผ๋กœ ๋‚˜ ํƒ€๋‚ฌ๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ GGBFS๊ฐ€ ๋งŽ์€ ๋ฐฐํ•ฉ์˜ ์‹œํ—˜์ฒด๊ฐ€ FA๊ฐ€ ๋งŽ ์€ ๋ฐฐํ•ฉ๋ณด๋‹ค ์ƒ๋Œ€์ ์œผ๋กœ UPV ์ฆ๊ฐ€์œจ์ด ํฌ๊ฒŒ ๋‚˜ํƒ€๋‚˜ ์ž๊ธฐ ์น˜์œ ์—๋Š” GGBFS์˜ ํ˜ผํ•ฉ๋ฅ ์„ ์ ์ • ์ˆ˜์ค€๊นŒ์ง€ ์ฆ๊ฐ€์‹œํ‚ค๋Š” ๊ฒƒ์ด ํšจ๊ณผ์ ์ผ ๊ฒƒ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค.

  • 2) ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜ ๋ชจ๋‘ ์นจ์ง€ 30์ผ๊นŒ์ง€์˜ UPV ์ฆ๊ฐ€์œจ์ด ์นจ์ง€ 30 ์ผ์—์„œ 60์ผ๊นŒ์ง€์˜ UPV ์ฆ๊ฐ€์œจ๋ณด๋‹ค ํฌ๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ์ด๋Š” ๊ท ์—ด ๋ฐœ์ƒ ํ›„ ์•ฝ 30์ผ๊นŒ์ง€ ๊ท ์—ด์˜ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๊ฐ€ ๊ฐ€์žฅ ํฌ ๊ณ  ์ดํ›„์—๋Š” ๊ฐ์†Œํ•˜๋Š” ๊ฒƒ์œผ๋กœ ์ƒ๊ฐ๋œ๋‹ค. ๋”ฐ๋ผ์„œ ๊ท ์—ด ๋ฐœ์ƒ ์ดˆ๊ธฐ์— ์ ์ ˆํ•œ ํ™˜๊ฒฝ์„ ์ œ๊ณตํ•˜์—ฌ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ๋†’์ผ ์ˆ˜ ์žˆ๋„๋ก ํ•ด์•ผ ํ•  ๊ฒƒ์ด๋‹ค.

  • 3) ์นจ์ง€ 30์ผ๊ณผ ์นจ์ง€ 30์ผ์—์„œ 60์ผ๊นŒ์ง€์˜ UPV ์ฆ๊ฐ€์œจ์€ ๋‹ด ์ˆ˜๋ณด๋‹ค ์ƒ๋Œ€์ ์œผ๋กœ ํ•ด์ˆ˜์—์„œ ํฌ๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ์ด๋Š” ํ•ด์ˆ˜์— ํฌํ•จ๋œ ๋‹ค์–‘ํ•œ ์ด์˜จ๋“ค์ด ๊ท ์—ด๋ฉด์˜ ์ž๊ธฐ์น˜์œ ์— ๊ธ์ •์ ์ธ ํšจ๊ณผ๋ฅผ ๋‚˜ํƒ€๋‚ด๋Š” ๊ฒƒ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค.

  • 4) ๋‹ด์ˆ˜์™€ ํ•ด์ˆ˜์— ์นจ์ง€ํ•œ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚ค์ง€ ์•Š์€ ์‹œํ—˜์ฒด์™€ ๊ท ์—ด์„ ๋ฐœ์ƒ์‹œํ‚จ ์‹œํ—˜์ฒด๊ฐ„์˜ UPV ์ฆ๊ฐ€์œจ ์ฐจ์ด๋ฅผ ํ†ตํ•ด ์žฌ ๋ นํšจ๊ณผ๋ฅผ ์ œ์™ธํ•œ ์ˆœ์ˆ˜ ์ž๊ธฐ์น˜์œ ํšจ๊ณผ๋ฅผ ๋ถ„์„ํ•˜์˜€๋‹ค. ๊ทธ ๊ฒฐ ๊ณผ ์นจ์ง€ 30์ผ๊นŒ์ง€๋Š” ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๊ฐ€ ์žฌ๋ น ํšจ๊ณผ๋ณด๋‹ค UPV ์ฆ๊ฐ€์— ํฐ ์˜ํ–ฅ์„ ๋ฏธ์น˜๊ณ , 30์ผ ์ดํ›„์—๋Š” ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ์™€ ์žฌ๋ น ํšจ๊ณผ๊ฐ€ ๋ชจ๋‘ ๊ฐ์†Œ ๋˜๋Š” ์žฌ๋ น ํšจ๊ณผ๊ฐ€ ์ž๊ธฐ์น˜์œ  ๋ณด๋‹ค ๋‹ค ์†Œ ํฌ๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋‹ค.

UPV ์ธก์ •์„ ํ†ตํ•ด ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๋ฅผ ์ธก์ •ํ•  ์ˆ˜ ์žˆ์—ˆ์œผ๋ฉฐ, ๋‹ด ์ˆ˜์™€ ํ•ด์ˆ˜ ๋ชจ๋‘ ์นจ์ง€ ํ›„ 30์ผ๊นŒ์ง€ ์ž๊ธฐ์น˜์œ  ํšจ๊ณผ๊ฐ€ ์žฌ๋ นํšจ๊ณผ ๋ณด๋‹ค ํฌ๊ณ , ๋‹ด์ˆ˜๋ณด๋‹ค๋Š” ํ•ด์ˆ˜๊ฐ€ ๊ท ์—ด๋ฉด์˜ ์ž๊ธฐ์น˜์œ ์— ๊ธ์ •์  ์ธ ํšจ๊ณผ๋ฅผ ๋‚˜ํƒ€๋‚ด์—ˆ๋‹ค.

๊ฐ์‚ฌ์˜ ๊ธ€

์ด ๋…ผ๋ฌธ์€ 2015๋…„๋„ ์ •๋ถ€(๊ต์œก๋ถ€)์˜ ์žฌ์›์œผ๋กœ ํ•œ๊ตญ์—ฐ๊ตฌ์žฌ ๋‹จ์˜ ์ง€์›์„ ๋ฐ›์•„ ์ˆ˜ํ–‰๋œ ์—ฐ๊ตฌ์ž„(NRF-2015R1D1A3A0101 9583).

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