[1] Huang Lihua, Li Yujing, Wang Yuefang,. Strengthening effects of BFRP on reinforced concrete beams [J]. Journal of Southeast University (English Edition), 2013, 29 (2): 182-186. [doi:10.3969/j.issn.1003-7985.2013.02.013]
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Strengthening effects of BFRP on reinforced concrete beams(
)
BFRP加固钢筋混凝土梁的加固效果
)Journal of Southeast University (English Edition)[ISSN:1003-7985/CN:32-1325/N]
- Volumn:
- 29
- Issue:
- 2013 2
- Page:
- 182-186
- Research Field:
- Civil Engineering
- Publishing date:
- 2013-06-20
Info
- Title:
- Strengthening effects of BFRP on reinforced concrete beams
- BFRP加固钢筋混凝土梁的加固效果
- Author(s):
- Huang Lihua; Li Yujing; Wang Yuefang
- School of Civil Engineering, Dalian University of Technology, Dalian 116023, China
- Keywords:
- basalt fiber reinforced polymer(BFRP); strengthening; reinforced concrete beam; experiment; strengthening guidelines
- PACS:
- TU375
- DOI:
- 10.3969/j.issn.1003-7985.2013.02.013
- Abstract:
- Reinforced concrete(RC)beams externally bonded with basalt fiber reinforced polymer(BFRP)are experimentally investigated by using different numbers of bonding plies, transverse anchorages as well as the initial conditions of strengthened beams. The performances of the BFRP strengthening are compared with those of the carbon fiber reinforced polymer(CFRP)and the glass fiber reinforced polymer(GFRP)under the same experimental condition. Experimental results indicate that the strength and ductility of the strengthened beam with two plies of the BFRP are improved remarkably than those with one ply. The strengthening effects of the BFRP lie between those of the CFRP and the GFRP. The BFRP strengthening is little influenced by pre-cracks of concrete. Most failures are caused by interfacial debonding induced by flexural cracks in the experiment. Clamping of U-wraps along the whole beam is less efficient than endpoint anchorage for increasing the ultimate load of the strengthened beam. Finally, the models suggested by the five guidelines for predicting the debonding strain of the CFRP are extended to the BFRP and the conservative estimates of the debonding strain of the BFRP are given as well.
- 通过改变加固的层数、横向锚固方式以及加固梁的初始条件, 对比CFRP和GFRP的加固效果, 对BFRP加固钢筋混凝土梁开展了实验研究.研究结果表明:相比1层BFRP, 2层BFRP能明显提高加固梁的强度和刚度;BFRP的加固效果介于CFRP和GFRP之间;混凝土的初始裂缝对BFRP加固效果影响很小.试验中加固梁的失效形式多为弯曲裂缝引起的界面剥离破坏.从提高加固梁的极限承载力来看, 沿全梁粘贴U形箍的锚固方式不如端部锚固效率高.最后, 将5个加固指导规程中给出的CFRP剥离应变计算公式推广到BFRP加固中, 得到保守的计算结果.
References:
[1] Yao J. Research advance in FRP-strengthened RC structures [J]. Bulletin of Science and Technology, 2004, 20(3):216-22.
[2] CRC Construction Innovation. Review of strengthening techniques using externally bonded fiber reinforced polymer composites [R]. Brisbane, Australia: CRC Construction Innovation, 2002.
[3] Xi R G, Li Z Y. Application prospect of basalt fiber [J]. Fiber Composites, 2003, 17(3):17-20.
[4] Ouyang L J, Ding B, Lu Z D. BFRP and its application review in structural strengthening [J]. Fiber Reinforced Plastics/Composites, 2010, 27(2):1-5.(in Chinese)
[5] Zhang X Y, Zou G P, Shen Z Q. Experimental research on continuous basalt fiber and basalt fibers reinforced polymers [C]// Proceedings of SPIE—The International Society for Optical Engineering. Nanjing, China, 2008: 73756C.
[6] Sim J S, Park C, Moon D Y. Characteristics of basalt fiber as a strengthening material for concrete structures [J]. Composites, Part B: Engineering, 2005, 36(6/7):504-512.
[7] Ludovico M D, Prota A, Manfredi G. Structural upgrade using basalt fibers for concrete externally bonding [J]. Journal of Composite for Construction, 2010, 14(5):541-552.
[8] Ouyang Y, Wang P, Li X. Experimental study on flexural RC beams strengthened with BFRP sheets [J]. Building Structure, 2008, 38(11):74-78.(in Chinese)
[9] Ye L P, Fang T Q, Yang Y X. Experimental research of flexural debonding performances about RC beams strengthened with CFRP sheets [J]. Building Structure, 2003, 33(2):61-65.(in Chinese)
[10] Choi H T, West J S, Soudki K A. Analysis of the flexural behavior of partially bonded FRP strengthened concrete beams [J]. Journal of Composites for Construction, 2008, 12(4):375-386.
[11] Saxena P, Toutanji H, Noumowe A. Failure analysis of FRP-strengthened RC beams [J]. Journal of Composites for Construction, 2008, 12(1): 2-14.
[12] China Construction Standardization Association. CECS146—2003 The technical specification for strengthening concrete structure with carbon fiber reinforced polymer laminates [S]. Beijing: China Planning Press, 2007.(in Chinese)
[13] ACI Committee. ACI440.2R Guide for the design and construction of externally bonded FRP systems for strengthening concrete structures [S]. Farmington Hills, USA: American Concrete Institute Committee, 2008.
[14] The Concrete Society. Technical Report No.55 Design guidance for strengthening concrete structures using fiber composite materials[R]. Berkshire: The Concrete Society, 2000.
[15] Japan Society of Civil Engineering. Recommendations for upgrading of concrete structures with use of continuous fiber sheets [S]. Tokyo, Japan: Japan Society of Civil Engineering, 2000.
[16] International Federation for Structural Concrete(fib). Bulletin No.14 Externally bonded FRP reinforcement for RC structures [R]. Lausanne, Switzerland: International Federation for Structural Concrete Technical Report, 2001.
[17] Chen J F, Teng J G. Anchorage strength models for FRP and steel plates bonded to concrete [J]. Journal of Structural Engineering, 2001, 127(7):784-79
Memo
- Memo:
-
Biography: Huang Lihua(1967—), female, associate professor, lhhang@dlut.edu.cn.
Citation: Huang Lihua, Li Yujing, Wang Yuefang.Strengthening effects of BFRP on reinforced concrete beams[J].Journal of Southeast University(English Edition), 2013, 29(2):182-186.[doi:10.3969/j.issn.1003-7985.2013.02.013]