1 College of Civil Engineering, Tongji University, Shanghai 200092; 2 Shanghai Key Laboratory of Engineering Structure Safety, Shanghai 200032; 3 College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058; 4 School of Civil Engineering, Chongqing University, Chongqing 400044;
Abstract: To further enhance the tensile capacity of high performance cementitious composites, a new kind of cementitious material ultra-high ductility cementitious composites (UHDCC) based on cement mortar, is developed with the help of ultra high molecular weight polyethylene (PE) fibers. Uniaxial tension test, compression test and three-point bending beam test were conducted to explore the basic mechanical properties of UHDCC in this paper. The uniaxial tension test results indicated that UHDCC exhibited outstanding strain hardening behavior and the multiple cracking pattern. At the ultimate state, the crack spacing of UHDCC was generally less than 2 mm with the crack widths less than 200 μm. The average tensile strength of UHDCC was 7.28 MPa, while the average tensile strain capacity reached 12% (the maximal one more than 13%). The compressive test results showed that the compressive strains corresponding to the 80% and 60% of the peak compressive strength in post-peak branch reached about 2.8% and 7.0%, exhibiting the superior compressive ductility. The flexural toughness index I10, I30, I50 and I60 of UHDCC were 10.1, 33.1, 54.4 and 65.6 respectively, indicating the ultra-high deformability of UHDCC.Moreover, the 3-point bending notched beam test and single crack tension test results demonstrated that the high ductility of UHDCC originates from the ultra-high crack bridging capacity.
1 Li V C, Leung C K Y. Steady-state and multiple cracking of short random fiber composites [J]. Journal of Engineering Mechanics,1992,118(11):2246. 2 Xu S L, Li H D. A review on the development of research and application of ultra high toughness cementitious composites [J]. China Civil Engineering Journal,2008,41(6):45(in Chinese). 徐世烺,李贺东.超高韧性水泥基复合材料研究进展及其工程应用[J].土木工程学报,2008,41(6):45. 3 Li V C, Mishra D K, Wu H C. Matrix design for pseudo-strain-hardening fiber reinforced cementitious composites [J]. Materials and Structures,1995,28(10):586. 4 中华人民共和国住房和城乡建设部.GB50011-2010建筑抗震设计规范[S].北京:中国建筑工业出版社,2010:14. 5 Japan Society of Civil Engineers Concrete Committee. Recommendations for design and construction of high performance fiber reinforced cement composites with multiple fine cracks [S]. Tokyo: Japan Society of Civil Engineers,2008. 6 Fischer G, Stang H, Dick-Nielsen L. Initiation and development of cracking in ECC materials: Experimental observations and modeling [C]∥The 6th International Conference on Fracture Mechanics of Concrete and Concrete Structures. Catania,2007:1517. 7 中华人民共和国国家发展和改革委员会.DL/T 5332-2005水工混凝土断裂试验规程[S].北京:中国电力出版社,2005:9. 8 Lepech M D, Li V C. Application of ECC for bridge deck link slabs [J]. Materials and Structures,2009,42(9):1185. 9 Wang S X, Li V C. Engineered cementitious composites with high-volume fly ash [J]. ACI Materials Journal,2007,104(3):233. 10 Yu J T, Lin J, Zhang Z, et al. Mechanical performance of ECC with high-volume fly ash after sub-elevated temperatures [J]. Construction and Building Materials,2015,99:82. 11 Ranade R, Li V C, Stults M D, et al. Composite properties of high-strength, high-ductility concrete [J]. ACI Materials Journal,2013,110(4):413. 12 Li H D. Experimental research on ultra high toughness cementitious composites [D]. Dalian: Dalian University of Technology,2008(in Chinese). 李贺东.超高韧性水泥基复合材料试验研究[D].大连:大连理工大学,2008. 13 American Society for Testing Material C1018-97. Standard test method for flexural toughness and first-crack strength of fiber-reinforced concrete using beam with third-point loading [S]. New York. ASTM International,1992. 14 Deng Z C, Zhang P F, Xue H Q. Flexural toughness of cellulose and hybrid fiber reinforced concrete beams [J]. Journal of Beijing University of Technology,2008,34(8):852(in Chinese). 邓宗才,张鹏飞,薛会青.纤维素纤维及混杂纤维混凝土的弯曲韧性[J].北京工业大学学报,2008,34(8):852. 15 Kanda T, Li V C. Multiple cracking sequence and saturation in fiber reinforced cementitious composites [J]. JCI Concrete Research and Technology Japan Concrete Institute,1998,9(2):19. 16 Yang E H, Wang S X, Yang Y Z, et al. Fiber-bridging constitutive law of engineered cementitious composites [J]. Journal of Advanced Concrete Technology,2008,6(1):181.
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2018, Vol. 32 
