ª Œª Œ 26ƒ 1A Á œ pp. 213 ~ 218 gj pœw y ey y gj p k p Characterization of Compressive Strength and Elastic Modulus of Recycled Aggregate Concre

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1 26ƒ 1A Á œ pp. 213 ~ 218 gj pœw y ey y gj p k p Characterization of Compressive Strength and Elastic Modulus of Recycled Aggregate Concrete with Respect to Replacement Ratios Á Á Á½ Sim, JongsungÁPark, CheolwooÁPark, Sung JaeÁKim, Yong Jae Abstract As a manufacturing process of recycled aggregate improves the quality of recycled aggregate shall be sufficient enough to be used for structural concrete. This study characterized compressive strength and elastic modulus of concrete that used recycled coarse and fine aggregate. Before the strength tests, the fundamental characteristics of recycled aggregate were preliminarily analyzed and the recycled aggregate satisfied the class 1 requirements in KS F As the replacement ratio increased, the compressive strength and elastic modulus of recycled aggregate concrete decreased. When the coarse and fine aggregates were completely replaced with the recycled, the compressive strength and elastic modulus were decreased by 13% and 31%, respectively. Based on the test results, this study suggests equations for predicting the compressive strength and elastic modulus of the recycled aggregate concrete with respect to the replacement ratio. The values from the equations were in good agreement with the test data from this study and others. Keywords: recycled aggregate, recycled aggregate concrete, compressive strength, elastic modulus š y t wš, gj p w w ƒ» k y y y ey mwš w. x y y KS F » w, y e y ƒw y gj p k w w ùkû. p y ey w k gj p 13% 31%ƒ w. w x» y ey y gj p k w,» ü x w k mw. w : y, y gj p,, k 1. p, š v ƒw yy gj p w». w gj p 70% wš», yw w gj p t w, j w w w. ù x ü w w ƒ ƒ š w w ü 2004 (2 6 8 m 3 )» * z Áw w m y œw ** Á z Áw w m y œw BK21 ( [email protected]) ***w w m y œw ****w» œ wz 40 œ ƒ w š š (w gœ xz, 2004). ƒ ƒw š. z ù w» w y gj p wš ù, ¾ w yw k ( m, 2004).» y w (û, 1995;, 2004; Hansen, 1992; Mukai, 1979; Rashwan, 1997; Salem, 2003) y y gj p 26ƒ 1A œ 213

2 ü w w. w y gj p f p gj p w š œ» 1% ƒ š w. p k 15% 20% w. ü y w gj p w y, y gj p» mwš k p q w ù ƒ y ey k wš w. 2. x t 1. y ey x Recycled Aggregate Replacement Ratio Specimen Coarse aggregate Fine aggregate NN - - RN Recycled 100% - RR30 Recycled 100% Recycled 30% RR60 Recycled 100% Recycled 60% RR Recycled 100% Recycled 100% x y ey y gj p k p q w» w t 1 5ƒ ey x w, y t, k w w w w w w. 2.1 w» s, w ƒ 1:1 yw œ w y š w KS F 2573(gj p ) 1 y y w (t 2, 3 ). e Property KS F 2573 Class 1 Class 2 Class 3 y 25 mm y» w x ww. y sw w KS F 2576( w x ) d w. d, y 0.71%» 0.4%» sw, s ù ƒ. y,»» ƒ q w» ƒ» w x w w. y» w d w» w, KS F 2510(gj p sw» x ) KS F 2514( k w» w w x ) w. x, 3% yùp e k y t w yƒ, k yùp» z ƒ 92%. y ƒ 90% ³ w 90% w. w w d w» w KS F 2511( sw (0.08 mm m w ) x ) w x w. x, y 2.1% 2.8% gj pt x 5% y t» w 7% w. p m sp p, yy ùv k š AE w. x ü y gj p w w e, x w w š w. y ey t 4 ey» w, š w 45 MPa, v 10 cm, œ» 5%, 44% w w. 2.2 x x ϕ100ü200 mm x œ 1 z t 2. Recycled Coarse Aggregate Natural Crushed C. A. RCA Quality Standard (MOCT) Used KS F 2527 Used Absorption (%) ß ß ß 3.0 ß 5.0 ß 7.0 Density (g/cm 3 ) à 2.2 à à Abrasion (%) ß 40 ß ß Solid Volume (%) à 55 à à Property KS F 2573 Class 1 Class 2 t 3. Recycled Fine Aggregate Natural F. A. RCA Quality Standard (MOCT) Used KS F 2527 Used Absorption (%) ß ß ß 5.0 ß 10.0 Density (g/cm 3 ) à 2.2 à à

3 kxwš 20Û2 o C 28 mw w. x KS F 2405(gj p x ) w w. k œ t w ƒ w» x w w x d w w. 3. x 3.1 v œ» gj p wt ww z d v œ» 1 ey w ùkü. v w 12 cm v ùkü. y eyw v 1cm ƒw, ey 100% k ey ƒw v 5cm ƒ ƒw. y w gj p f pƒ w š, q x eš ù xk ƒ ù, ey y ƒ š j ü w xk, š vƒ j gj p, vg w f p y gj pƒ y w ùkù. œ» 4.3%, y ey 0.4% ƒ ey ƒw w ƒ w ùkü. w, 1 w y ey œ» y w ùkû. y w gj p v œ» - p,, y œ, yy yy ƒ ùký, x w mw v œ» w p q w w. 1. y ey v œ» y 2. y ey y 3.2 d 2 w. y ey ƒw w w ùkü. y 100% eyw 2MPa x, y eyw 4MPa ƒ x ùkû. w y ey»» ey 30% ü, w, ey 30%»»ƒ j ùkû. (2004) w y ey 60%»» ƒw ùkû. y gj p ey 30-60% j y ƒ. w w y ey y gj p w wš w, (1) w. w g j p» y ey z š w, w xk w. w w x x l y gj p w x y w y w j q, ey w w (1) xk w. w w x w x ƒ v wù, y gj p y t w j» j, w x ƒ ü w z w» w, š w y w w MPa y gj p ww. f = ckr f ck G 0.04S», f ckr y gj p (MPa), f ck gj p (MPa), G y ey (%), S y ey (%). x l y gj p (1) 26ƒ 1A œ 215

4 3.» x» (½, 2004; ½, 2003; ½y, 2003;, 2001;, 2001; ³, 1999, 2003; x, 2001;, 2002;, 2004a, 2004b;, 2003) w (1) Á mw. 3» y gj p x x w ü x d w ùküš. 3 w d w ƒ š w. 30 MPa w x w û w š ù,» j q, w ww k. = y ey y t 4. gj p w Specimen NN W/C(%) S/a (%) W C 4. k d gj p wš yw w, y w gj p, w x w» y q. 3.3 k x l w k 4 ùkù ƒ y ey ƒw k w. y eyw gj p k 8GPa d. t 5 x w y gj p d k (2) xw gj p» (gj p ƒ 30 MPa ) gj p k w ùküš. E c 0.03ω1.5 f ck ( f ck 30MPa, w = 1, 450~2,500kg m 3 ) (2) Unit volume weight (kg/m 3 ) C. A. F. A. Natural Recycled Natural Recycled RN RR RR RR t 5. k d HRWRA (kg) AE (g) Specimen f ck E, by test E, by KCI E, from eq. (3) (MPa) Reduction (%) (MPa) Reduction (%) (MPa) Reduction (%) (MPa) Reduction (%) NN ,185-29, RN % 20, % 29, % % RR % 17, % 29, % % RR % 20, % 28, % % RR % 16, % 28, % % 216

5 », E c gj p k (MPa), w gj p (kg/m 3 ), f ck gj p (MPa). x gj p d 5GPa ƒ w. k z w w w w x ƒ w q. ù y gj p ey ƒw k gj p w j ùkù, w xw gj p» w x w wš. 4 xw gj p» k»» y w ùkùš, gj p k y gj p w w q y gj p w k w. E = cr 0.03ω1.5 f ckr +(, 14.2G 10.9S) ( f ck 30MPa, w 1, 450~2, 500kg m 3 = )», E cr y w w gj p k (MPa), w gj p (kg/m 3 ), f ckr y gj p y gj p (MPa), G y ey (%), S y ey (%).» w k x w» š ƒ w, gj p k w ey w w ƒw y gj p y ey k š w. w, 4 ey ƒw y gj p k y w. ƒ x l y gj p k» 5. k» x (3) (½, 2004;, 2001; ³, 2003;, 2002) w (3) Á mw 5 ùkü. 5 w (3) w x w z, xw gj p» gj p( 30 MPa ) k y gj p w. 5 l w y gj p k yw w ùkû, w xw g j p» y w gj p š w w š y w» ƒ j. xw gj p» w y gj p k w j k ƒ û, y w w, y gj p ƒ û ù y ey, j w. 4. š y w gj p gj p p ƒ, w y gj p w, gj p ù w ƒ» e k p w. w w k y gj p gj p w vƒ j y x» w q. w y gj p y ey œ» y j w q. ù y ey ƒw w, eyw 4% eyw 13% x. w p» y y ey w w,» mw yw. w, y gj p k d w, w ùkü. w y ey k s eyw 15%, y eyw 31% ƒ. w x k y ey k w w, k» w de eƒ w. y w gj p k w ey w w, w y w gj p ù w y w q. w x, w œw ƒ 26ƒ 1A œ 217

6 q. w y» w sgj p š ƒƒe y» w w w s gj p š ƒƒe y w» y w. š x m (2004) y t» ( ). pp ½, «t, t, y (2003) w gj p» w x. w gj pwz ƒ w tz, 15«, 2y, pp ½,, y, ½ûy(2004) gj p q p x. w wz, w wz 6«, 1y, pp ½y,,,, x(2003) w gj p w p w x. w gj pwz w tz, 15«, 1y, pp û (1995) gj p œw p w x. w, û w, pp , k ³, (2001) v yww gj p ü. w gj pwz, w gj pwz, 13«, 1y, pp , y, x, x³(2004) t p w. w wz w t z, 2004, pp , y, t,,, ½ w(2001) s» š gj p p w x. w gj pwz w tz, 13«, 1y, pp ³, y(1999) ey gj p w p. w gj pwz ƒ w tz, 11«, 2y, pp ³, y, y(2003) gj p ü w x. wm wz, wm wz, 23«, 1Ay, pp x, ey(2001) š gj p p. w gj pwz, w gj pwz, 13«, 6y, pp (2004) v e p w v y gj p sƒ. w, w w, pp ,,,, ½ (2004a) t gj p œw p. w gj pwz ƒ w tz, 16«, 2y, pp ,, ½ (2004b) št w gj p p. w gj pwz w tz, 16«, 1 y, pp ,,», ½w, (2002) ƒ gj p e w. w gj pwz ƒ w tz, 14«, 2y, pp , y, ¼x(2003) gj p yw gj p. wm wz»w z, pp w gœ xz(2004) w. pp Hansen, T.C. (1992) Recycling of Demolished Concrete and Masonry. Report of Technical Committee 37-DRC, Demolition and Reuse of Concrete, RILEM, Routledge, Mukai, T. et al. (1979) Study on Reuse of Waste Concrete for Aggregate of Concrete. Proc. Energy and Resources Conservation in Concrete Technology, Japan-US Cooperative Science Programme, San Francisco, US. Rashwan, M.S. and Abourizk, S. (1997) The Properties of Recycled Concrete, Concrete International, ACI, Vol. 19, No. 7, pp Salem, R.M., Burdette, E.G.SGand Jackson, N.M. (2003) Resistance to Freezing and Thawing of Recycled Aggregate Concrete. ACI Materials Journal, ACI, Vol. 100, No. 3, pp ( : / : / : ) 218