Tian et al 2021a - Revision history

Rimni at 14:47, 14 December 2021

2021-12-14T14:47:32Z

Rimni at 10:32, 27 August 2021

2021-08-27T10:32:04Z

Rimni: /* References */

2021-08-19T11:34:20Z

‎References

Rimni: /* References */

2021-08-19T11:33:27Z

‎References

Rimni at 10:50, 19 August 2021

2021-08-19T10:50:02Z

Rimni: /* List of symbols */

2021-08-19T10:29:14Z

‎List of symbols

Rimni at 10:27, 19 August 2021

2021-08-19T10:27:22Z

Rimni at 10:13, 19 August 2021

2021-08-19T10:13:58Z

Rimni: /* 4.4 Mechanism of failure */

2021-08-19T10:13:21Z

‎4.4 Mechanism of failure

Rimni at 10:09, 19 August 2021

2021-08-19T10:09:57Z

@@ Line 334: / Line 334: @@
 ==4. Analysis and results==
-===4.1. Initiation of cracks===
+===4.1 Initiation of cracks===
 The crack patterns of reinforced concrete beams strengthened with CFRP were quite different from those of control beams. Compared with the control beams there were more cracks with marrow spacing. The reason is that the beams strengthened with CFRP have greater shear strength in shear span, which leads to narrow cracks. Therefore, the beams revealed another critical crack in that area as well. However, Compared with the control beam, the critical crack in the shear span has been identified. Compared with the reinforced concrete control beam, the path of using CFRP can make the cracks get narrower dispersion. The shear crack patterns of beams strengthened with CFRP are shown in [[#img-5|Figures 5]] and [[#img-6|6]].

@@ Line 349: / Line 349: @@
 |  style="text-align: center;font-size: 75%;"|(b) Beam with stirrups
 |- style="text-align: center; font-size: 75%;"
-| colspan="2" style="padding:10px;"| '''Figure 5'''. Shear Cracks Pattern of CFRP Strengthened Beams by 90°
+| colspan="2" style="padding:10px;"| '''Figure 5'''. Shear cracks pattern of CFRP strengthened beams by 90°
 |}
@@ Line 366: / Line 366: @@
 | colspan="2" style="padding:10px;"| '''Figure 6'''. Shear cracks pattern of CFRP strengthened beams by 45°
 |}
 ===4.2 Damage of beam===

@@ Line 559: / Line 559: @@
 [10]  Bazant P.Z.,  Kim J.K.. Size effect in shear failure of longitudinally reinforced beams. ACI Journal, 81(5):456-468, 1984.
-[11] P.Z. Bazant,  Yu Q. Designing against size effect on shear strength of reinforced concrete beams without stirrups. J. Struct. Eng., 131(12):1877-1885, 2005.
+[11]  Bazant P.Z.,  Yu Q. Designing against size effect on shear strength of reinforced concrete beams without stirrups. J. Struct. Eng., 131(12):1877-1885, 2005.
 [12] Arslan G. Cracking shear strength of RC slender beams without stirrups. J. Civ. Eng. Manag.,  14(3):177-182, 2008.

@@ Line 537: / Line 537: @@
 ==References==
 [1] Maruyama K. JSCE recommendations for upgrading of concrete structures with use of continuous fiber sheets. FRP Composites in Civil Engineering, 2001.
@@ Line 556: / Line 557: @@
 [9]  Wight J.K., MacGregor J.G.   Reinforced concrete: Mechanics and design. 6th ed., Prentice Hall, p. 1176, 2011.
-[10] P.Z. Bazant, J. K. Kim “Size effect in shear failure of longitudinally reinforced beams,” ACI Journal, pp. 81: 456-468, 1984.
+[10]  Bazant P.Z.,  Kim J.K.. Size effect in shear failure of longitudinally reinforced beams. ACI Journal, 81(5):456-468, 1984.
-[11] P.Z. Bazant, Q. Yu “Designing against size effect on shear strength of reinforced concrete beams without stirrups,” J. Struct. Eng., no. 2005, pp. 131(12):1877-1885.
+[11] P.Z. Bazant,  Yu Q. Designing against size effect on shear strength of reinforced concrete beams without stirrups. J. Struct. Eng., 131(12):1877-1885, 2005.
-[12] G. Arslan “Cracking shear strength of RC slender beams without stirrups.” J. Civ. Eng. Manag., no. 2008, pp. 14(3):177-182.
+[12] Arslan G. Cracking shear strength of RC slender beams without stirrups. J. Civ. Eng. Manag.,  14(3):177-182, 2008.
-[13] G. Arslan “Shear strength of reinforced concrete beams with stirrups,” J.Mater. Struct. no. 2008, pp. 41:113-122.
+[13]  Arslan G. Shear strength of reinforced concrete beams with stirrups. J. Mater. Struct., 41:113-122, 2008.
-[14] I.A. Bukhari, S.  Ahmad “Evaluation of shear strength of high-strength concrete beams without stirrups.” Arab. J. Sci. Eng., no. 2007, pp. 33(2B):321-336.
+[14]  Bukhari I.A.,   Ahmad S. Evaluation of shear strength of high-strength concrete beams without stirrups. Arab. J. Sci. Eng., 33(2B):321-336, 2007.
-[15] J. Song, W.H. Kang “Probabilistic shear strength models for reinforced concrete beams without shear reinforcement,” Struct. Eng. Mech., no. 2010, pp. 31(1):15-38.
+[15]  Song J.,  Kang W.H. Probabilistic shear strength models for reinforced concrete beams without shear reinforcement. Struct. Eng. Mech., 31(1):15-38, 2010.
-[16] W.W. Kuo, T.J. Cheng, S. J. Hwang “Force transfer mechanism and shear strength of reinforced concrete beams,” J. Eng. Struct., no. 2012, pp. 32:1537-1546.
+[16]  Kuo W.W.,  Cheng T.J.,  Hwang S.J. Force transfer mechanism and shear strength of reinforced concrete beams. J. Eng. Struct., 32:1537-1546, 2012.
-[17] P.D. Zararis “Shear strength and minimum shear reinforcement of reinforced concrete slender beams.” ACI Struct. J., no. 2003, pp. 100(2):203-214.
+[17]  Zararis P.D. Shear strength and minimum shear reinforcement of reinforced concrete slender beams. ACI Struct. J., 100(2):203-214, 2003.
-[18] A.K. Tureyen, R.J. Frosch “Concrete strength: another perspective,” ACI Struct. J., no. 2003, pp. 100(5):609-610.
+[18]  Tureyen A.K.,  Frosch R.J. Concrete strength: another perspective. ACI Struct. J., 100(5):609-610, 2003.
-[19] A. Khalifa, W.J. Gold, A.Nanni, A.M.I. Aziz “Contribution of externally bonded FRP to shear capacity of RC flexural members,” J. Compos. Constr. vol. 2, no. 4, pp. 195–202, 1998.
+[19]  Khalifa A.,  Gold W.J., Nanni A.,  Aziz A.M.I. Contribution of externally bonded FRP to shear capacity of RC flexural members. J. Compos. Constr., 2(4):195–202, 1998.

@@ Line 540: / Line 540: @@
 [1] Maruyama K. JSCE recommendations for upgrading of concrete structures with use of continuous fiber sheets. FRP Composites in Civil Engineering, 2001.
-[2] 400 ACI C. Guide for the Design and Construction of Externally Bonded FRP Systems for strengthening concrete structures. American Concrete Institute, 2004.
+[2] 400 ACI C. Guide for the design and construction of externally bonded FRP systems for strengthening concrete structures. American Concrete Institute, 2004.
-[3] H. A. Toutanji, T. El-Korchi, R. N. Katz, and G. L. Leatherman, “Behaviour of carbon fiber reinforced cement composites in direct tension,” Cem. Concr. Res., vol. 23, no. 3, pp. 618–626, 1993, doi: 10.1016/0008-8846(93)90013-Y.
+[3]  Toutanji H.A.,  El-Korchi T.,  Katz R.N.,   Leatherman G.L. Behaviour of carbon fiber reinforced cement composites in direct tension. Cem. Concr. Res., 23(3):618–626, 1993.
-[4] A. Khalifa, A. Nanni “Improving shear capacity of RC T-section beams using CFRP Composites.,” Cem. Concr. Compos. no. 2000, pp. 22:165-174.
+[4]  Khalifa A.,  Nanni A. Improving shear capacity of RC T-section beams using CFRP composites. Cem. Concr. Compos., 22(3):165-174, 2000.
-[5] O. C. A. Bousselham, “Behavior of reinforced concrete T-beams strengthened in shear with carbon fiber-reinforced polymer - An experimental study,” Aci Struct. J. 103(3), vol. 103(3), pp. 339–347, 2006.
+[5]  Bousselham O.C.A. Behavior of reinforced concrete T-beams strengthened in shear with carbon fiber-reinforced polymer - An experimental study. Aci Struct. J., 103(3):339–347, 2006.
-[6] Y. T. Obaidat, S. Heyden, and O. Dahlblom, “The effect of CFRP and CFRP / concrete interface models when modelling retrofitted RC beams with FEM,” Compos. Struct. vol. 92, no. 6, pp. 1391–1398, 2010, doi: 10.1016/j.compstruct.2009.11.008.
+[6] Obaidat  Y.T.,  Heyden S.,   Dahlblom O. The effect of CFRP and CFRP / concrete interface models when modelling retrofitted RC beams with FEM. Compos. Struct., 92(6):1391–1398, 2010.
-[7] O. A. Farghal, “Fatigue behavior of RC T-beams strengthened in shear with CFRP strips,” Ain Shams Eng. J., vol. 5, no. 3, pp. 667–680, 2014, doi: 10.1016/j.asej.2014.03.007.
+[7]  Farghal O.A. Fatigue behavior of RC T-beams strengthened in shear with CFRP strips. Ain Shams Eng. J., 5(3):667–680, 2014.
-[8] GB50010-2010, Code for Design of Concrete Structures [S].  Ministry of Housing and Urban-Rural Development of the People's Republic of China, 2015.
+[8] GB50010-2010: Code for design of concrete structures.  Ministry of Housing and Urban-Rural Development of the People's Republic of China, 2015.
-[9] J.G. MacGregor, J.W. Wight “Mechanics and Design,” in Reinforced concrete, 6th ed., Prentice Hall, 2008, p. 1176.
+[9]  Wight J.K., MacGregor J.G.   Reinforced concrete: Mechanics and design. 6th ed., Prentice Hall, p. 1176, 2011.
 [10] P.Z. Bazant, J. K. Kim “Size effect in shear failure of longitudinally reinforced beams,” ACI Journal, pp. 81: 456-468, 1984.

@@ Line 479: / Line 479: @@
 ==List of symbols==
-The meanings of the symbols in this study are as follow
+The meanings of the symbols in this study are as follow:
 {| style="width: 100%;border-collapse: collapse;"
 |-
-|  style="border-top: 2pt solid black;border-bottom: 1pt solid black;"|Parameter
+|  <math>{A}_{fv}</math>: Area of CFRP strip
-|  style="border-top: 2pt solid black;border-bottom: 1pt solid black;"|
-|  style="border-top: 2pt solid black;border-bottom: 1pt solid black;"|meaning
-|-
-|  style="border-top: 1pt solid black;"|<math>{A}_{fv}</math>: Area of CFRP strip
 |-
 | <math>{f}_{fe\, }</math>: Effective stress of CFRP strip
@@ Line 527: / Line 523: @@
 | <math>a</math>: Shear span length
 |}
 ==Data availability==

@@ Line 463: / Line 463: @@
 As shown in the above [[#img-7|Figures 7]] and [[#img-8|8]], failure in adhesive showing debonding and vertical crack initiation in shear span starting in tension face of the beam through the neutral axis and then reached to compression zone which causes concrete crushing in the zone of compression beneath the points of loading.
-==5 Conclusion==
+==5. Conclusion==
 For this research, a new model of shear strength was developed to precisely quantify the shear strength in RC beams increases due to strengthened with CFRP strips. The finite element results indicated that it is useful to strengthen RC beams with CFRP strips. The conclusion are as following:
@@ Line 475: / Line 475: @@
 (4) In the present research, the RC beams without shear stirrups strengthened with CFRP strips, a large increase was obtained in the shear strength capacity compared with the RC beams with stirrups strengthened with CFRP.
-<span id='_Hlk47253988'></span><span id='_Hlk47253934'></span>(5) The highest load and deflection is a little affected by the CFRP strips orientation. CFRP strips orientation for 45°, a large increase in load-carrying capacity is gained compared to 90°.
+(5) The highest load and deflection is a little affected by the CFRP strips orientation. CFRP strips orientation for 45°, a large increase in load-carrying capacity is gained compared to 90°.
 The meanings of the symbols in this study are as follow
@@ Line 485: / Line 487: @@
 |  style="border-top: 2pt solid black;border-bottom: 1pt solid black;"|meaning
 |-
-|  style="border-top: 1pt solid black;"|<math>{A}_{fv}</math>
+|  style="border-top: 1pt solid black;"|<math>{A}_{fv}</math>: Area of CFRP strip
-|  style="border-top: 1pt solid black;"|=
-|  style="border-top: 1pt solid black;"|Area of CFRP strip
 |-
-| <math>{f}_{fe\, }</math>
+| <math>{f}_{fe\, }</math>: Effective stress of CFRP strip
-| =
-| Effective stress of CFRP strip
 |-
-| <math>{h}_{fv}</math>
+| <math>{h}_{fv}</math>: Depth of CFRP strip
-| =
-| Depth of CFRP strip
 |-
-| <math>{S}_{f}</math>
+| <math>{S}_{f}</math>: Spacing between CFRP strips
-| =
-| Spacing between CFRP strips
 |-
-| <math>{t}_{f}</math>
+| <math>{t}_{f}</math>: The thickness of CFRP strip
-| =
-| The thickness of CFRP strip
 |-
-| <math>{E}_{f}</math>
+| <math>{E}_{f}</math>: Tensile modulus of elasticity of carbon fiber reinforcement
-| =
-|  colspan='3' |Tensile Modulus of elasticity of carbon fiber reinforcement
 |-
-| <math>{\epsilon }_{fu}</math>
+| <math>{\epsilon }_{fu}</math>: Design rapture strain of CFRP
-| =
-| Design rapture strain of CFRP
 |-
-| <math>{K}_{1}</math>
+| <math>{K}_{1}</math>: Modification factor applied to <math display="inline">{K}_{v}</math> to account for concrete strength
-| =
-| Modification factor applied to <math display="inline">{K}_{v}</math> to account for concrete strength
 |-
-| <math>{K}_{2}</math>
+| <math>{K}_{2}</math>: Modification factor applied to <math display="inline">{K}_{v}</math> to account for Wrapping Scheme
-| =
-| Modification factor applied to <math display="inline">{K}_{v}</math> to account for Wrapping Scheme
 |-
-| <math>{L}_{e}</math>
+| <math>{L}_{e}</math>: Bond length
-| =
-| Bond length
 |-
-| <math>{f}_{cm}</math>
+| <math>{f}_{cm}</math>: Mean characteristic value of axial compressive strength of concrete
-| =
-|  colspan='3' |Mean Characteristic value of axial compressive strength of concrete
 |-
-| <math>{h}_{fv}</math>
+| <math>{h}_{fv}</math>: Depth of CFRP strip
-| =
-| Depth of CFRP strip
 |-
-| <math>{\alpha }_{cv}</math>
+| <math>{\alpha }_{cv}</math>: Is the factor that accounts for the influence of loading type and shear span to depth ratio on the shear strength of beams
-| =
-|  colspan='2' |Is the factor that accounts for the influence of loading type and shear span to depth ratio on the shear strength of beams
 |-
-| <math>{h}_{o}</math>
+| <math>{h}_{o}</math>: The effective depth of the section
-| =
-|  colspan='2' |The effective depth of the section
 |-
-| <math>{f}_{ym}</math>
+| <math>{f}_{ym}</math>: Mean characteristic value of compressive strength of ordinary steel reinforcement
-| =
-|  colspan='2' |Mean Characteristic value of compressive strength of ordinary steel reinforcement
 |-
-| <math>{A}_{sv}</math>
+| <math>{A}_{sv}</math>: Area of shear stirrups (shear steel)
-| =
-|  colspan='2' |Area of shear stirrups (shear steel)
 |-
-|  style="text-align: center;"|b
+|  <math>b</math>: Width of reinforcement section
-| =
-|  colspan='2' |Width of reinforcement section
 |-
-|  style="text-align: center;"|h
+| <math>h</math>: Depth of section
-| =
-|  colspan='2' |Depth of section
 |-
-| <math>{h}_{o}</math>
+| <math>{h}_{o}</math>: The effective depth of the section
-| =
-|  colspan='2' |The effective depth of the section
 |-
-|  style="border-bottom: 2pt solid black;text-align: center;"|a
+| <math>a</math>: Shear span length
-|  style="border-bottom: 2pt solid black;"|=
-|  colspan='2'  style="border-bottom: 2pt solid black;"|Shear span length
 |}
-===Data Availability===
+==Data availability==
 The raw/processed data required to reproduce these findings cannot be shared at this time as the data also form part of an ongoing study.
-===Conflicts of Interest===
+==Conflicts of Interest==
 The authors declare that they have no conflicts of interest.
-===Funding Statement===
+==Funding Statement==
 This study was supported by the Fundamental Research Funds for the Central Universities CHD (300102281206).
-===Reference===
+==References==
-[1] Maruyama, K. JSCE recommendations for upgrading of concrete structures with use of continuous fiber sheets [J]. FRP Composites in Civil Engineering, 2001.
+[1] Maruyama K. JSCE recommendations for upgrading of concrete structures with use of continuous fiber sheets. FRP Composites in Civil Engineering, 2001.
-[2] 400 ACI C. Guide for the Design and Construction of Externally Bonded FRP Systems for strengthening concrete structures[M]. American Concrete Institute, 2004.
+[2] 400 ACI C. Guide for the Design and Construction of Externally Bonded FRP Systems for strengthening concrete structures. American Concrete Institute, 2004.
 [3] H. A. Toutanji, T. El-Korchi, R. N. Katz, and G. L. Leatherman, “Behaviour of carbon fiber reinforced cement composites in direct tension,” Cem. Concr. Res., vol. 23, no. 3, pp. 618–626, 1993, doi: 10.1016/0008-8846(93)90013-Y.

@@ Line 457: / Line 457: @@
 |style="padding:10px;"| [[Image:Review_197528335498-image38.jpeg|center|288px]]
 |- style="text-align: center; font-size: 75%;"
-| colspan="1" style="padding:10px;"| '''Figure 11'''. Shear span CFRP debonding failure
+| colspan="2" style="padding:10px;"| '''Figure 11'''. Shear span CFRP debonding failure
 |}

← Older revision		Revision as of 10:13, 19 August 2021
Line 447:		Line 447:
	\| colspan="2" style="padding:10px;"\| '''Figure 10'''. Strengthened beam and control beam mode of failure		\| colspan="2" style="padding:10px;"\| '''Figure 10'''. Strengthened beam and control beam mode of failure
	\|}		\|}
−
−
−	~~<div class="center" style="width: auto; margin-left: auto; margin-right: auto;">~~
−	~~[[Image:Review_197528335498-image31.jpeg\|288px]] </div>~~
−
−	~~<div class="center" style="width: auto; margin-left: auto; margin-right: auto;">~~
−	~~<span style="text-align: center; font-size: 75%;">'''Beam W1'''</span></div>~~
−
−	~~<div class="center" style="width: auto; margin-left: auto; margin-right: auto;">~~
−	~~[[Image:Review_197528335498-image32.jpeg\|288px]] </div>~~
−
−	~~<div class="center" style="width: auto; margin-left: auto; margin-right: auto;">~~
−	~~<span style="text-align: center; font-size: 75%;">'''Beam W2 '''</span></div>~~
−
−	~~<div class="center" style="width: auto; margin-left: auto; margin-right: auto;">~~
−	~~[[Image:Review_197528335498-image33.jpeg\|288px]] </div>~~
−
−	~~<div id="_Toc38854670" class="center" style="width: auto; margin-left: auto; margin-right: auto;">~~
−	~~<span style="text-align: center; font-size: 75%;">'''Beam W3'''</span></div>~~
−
−	~~<div class="center" style="width: auto; margin-left: auto; margin-right: auto;">~~
−	~~[[Image:Review_197528335498-image34.jpeg\|288px]] </div>~~
−
−	~~<div class="center" style="width: auto; margin-left: auto; margin-right: auto;">~~
−	~~<span style="text-align: center; font-size: 75%;">'''Beam S1'''</span></div>~~
−
−	~~<div class="center" style="width: auto; margin-left: auto; margin-right: auto;">~~
−	~~<span style="text-align: center; font-size: 75%;">''' [[Image:Review_197528335498-image35.jpeg\|288px]] '''</span></div>~~
−
−	~~<div class="center" style="width: auto; margin-left: auto; margin-right: auto;">~~
−	~~<span style="text-align: center; font-size: 75%;">'''Beam S2'''</span></div>~~
−
−	~~<div class="center" style="width: auto; margin-left: auto; margin-right: auto;">~~
−	~~<span style="text-align: center; font-size: 75%;">''' [[Image:Review_197528335498-image36.jpeg\|288px]] '''</span></div>~~
−
−	~~<div class="center" style="width: auto; margin-left: auto; margin-right: auto;">~~
−	~~<span style="text-align: center; font-size: 75%;">'''Beam S3'''</span></div>~~
−
−	~~<div class="center" style="width: auto; margin-left: auto; margin-right: auto;">~~
−	~~<span style="text-align: center; font-size: 75%;">'''Figure 10: Strengthened Beam and Control Beam Mode of Failure'''</span></div>~~

@@ Line 423: / Line 423: @@
 The mean shear failure of the strengthened beam with CFRP is debonding of CFRP strips from the beam. When the beams generate cracks in shear span, debonding will occur. Reinforced concrete beams also exhibit other forms of failure, such as shear stirrups yielding and concrete crushing under compression. The failure mechanisms of control beams with stirrups and without stirrups were both predictable. The mechanisms of failure were examined established on displacement control as the case for cracks distribution rather than force control. The mode of failure of control RC beams and CFRP strengthened beam as shown in [[#img-10|Figure 10]]. The concrete strain of all reinforced concrete beams under load is about 0.0062. This strain is greater than the ultimate compressive strain of concrete. [[#img-4|Figures 4]] and [[#img-8|8]] clearly shows the crushing failure of concrete.
 <div class="center" style="width: auto; margin-left: auto; margin-right: auto;">
@@ Line 463: / Line 488: @@
 <span style="text-align: center; font-size: 75%;">'''Figure 10: Strengthened Beam and Control Beam Mode of Failure'''</span></div>
-{|
+<div id='img-11'></div>
 |-
-| [[Image:Review_197528335498-image37.jpeg|288px]]
+|style="padding:10px;"|  [[Image:Review_197528335498-image37.jpeg|288px]]
-| [[Image:Review_197528335498-image38.jpeg|center|288px]]
+|style="padding:10px;"| [[Image:Review_197528335498-image38.jpeg|center|288px]]
 |}
-<div id="_Toc38854671" class="center" style="width: auto; margin-left: auto; margin-right: auto;">
+As shown in the above [[#img-7|Figures 7]] and [[#img-8|8]], failure in adhesive showing debonding and vertical crack initiation in shear span starting in tension face of the beam through the neutral axis and then reached to compression zone which causes concrete crushing in the zone of compression beneath the points of loading.
-<span style="text-align: center; font-size: 75%;">'''Figure 11: Shear span CFRP Debonding Failure'''</span></div>
-−
-As shown in the above Figure 7 and 8, failure in adhesive showing debonding and vertical crack initiation in shear span starting in tension face of the beam through the neutral axis and then reached to compression zone which causes concrete crushing in the zone of compression beneath the points of loading.
 ==5 Conclusion==