硫酸钙对高韧性水泥基复合材料力学性能的影响
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摘要
采用在PVA-ECC中掺入硫酸钙来提高其力学性能,通过立方体抗压强度试验和四点弯试验分析硫酸钙对PVA-ECC力学性能的影响。另外,利用CT扫描和电镜扫描分析了硫酸钙的微细观作用机理。结果表明:适当掺入硫酸钙可使PVA-ECC基体更加密实,激发粉煤灰活性,从而提高PVA-ECC的抗压强度和抗弯强度,同时能较好地保持PVA-ECC良好的弯曲韧性和裂缝控制能力。
Calcium sulfate was adopted to improve the mechanic performance of PVA-ECC and effects of calcium sulfate on mechanical performance of PVA-ECC was studied through uniaxial compressive and four-point bending test.Moreover,porosity was determined by X-ray computed tomography(CT)scanning and morphology of fibers at the fracture face were characterized via scanning electron microscopy(SEM).Experimental results indicated that ECC with calcium sulfate achieved both higher compressive and bending strength for its more compact microstruture,meanwhile the inherent high toughness of PVA-ECC and crack-controlling ability of was sustained.
Calcium sulfate was adopted to improve the mechanic performance of PVA-ECC and effects of calcium sulfate on mechanical performance of PVA-ECC was studied through uniaxial compressive and four-point bending test.Moreover,porosity was determined by X-ray computed tomography(CT)scanning and morphology of fibers at the fracture face were characterized via scanning electron microscopy(SEM).Experimental results indicated that ECC with calcium sulfate achieved both higher compressive and bending strength for its more compact microstruture,meanwhile the inherent high toughness of PVA-ECC and crack-controlling ability of was sustained.
引文
[1]LI V C,WANG S,WU C.Tensile strain-hardening behavior of polyvinyl alcohol engineered cementitious composite(PVA-ECC)[J].ACI Mater J,2001(98):483-492.
[2]YANG E H,YANG Y,LI V C.Use of high volumes of fly ash to improve ECC mechanical properties and material greenness[J].ACIMater J,2007,104(6):303-311.
[3]徐世烺,李贺东.超高性能水泥基复合材料直接拉伸试验研究[J].土木工程学报,2009,42(9):32-41.
[4]MA H,LI V C.Tailoring engineered cementitious composites with local ingredients[J].Construction and Building Materials,2015(101):584-595.
[5]WANG S,LI V C.Engineered cementitious composites with highvolume fly ash[J].ACI Mater J,2007,104(3):233-241.
[6]PAN Z,WU C,LIU J.Study on mechanical properties of cost-effective polyvinyl alcohol engineered cementitious composites(PVA-ECC)[J].Construction and Building Materials,2015(78):397-404.
[7]YU J,et al.Strength improvement of strain-hardening cem-entitious composites with ultrahigh-volume fly ash[J].Journal of Materials in Civil Engineering,2017,29(9):05017003.
[8]XU A,SARKAR S L.Microstructural study of gypsum activated fly ash hydration in cement paste[J].Cement Concrete Research,1991(21):1137-1147.
[9]MA W,LIU C,BROWN P W,et al.Pore strutures of fly ashes activated by Ca(OH)2and CaSO4·2H2O[J].Cement Concrete Research,1995,25(2):417-425.
[10]POON C S,KOU S S,LAM L,et al.Activation of fly ash/cement systems using calcium sulfate anhydrite[J].Cement Concrete Research,2001(31):873-881.
[11]刘京红,史攀飞,杨跃飞,等.基于CT试验的混凝土裂纹扩展演化研究[J].混凝土,2017(4):74-77.
[12]玻璃纤维增强水泥性能试验方法抗弯性能:GB/T 15231-2008[S].中国标准出版社,1994.
[2]YANG E H,YANG Y,LI V C.Use of high volumes of fly ash to improve ECC mechanical properties and material greenness[J].ACIMater J,2007,104(6):303-311.
[3]徐世烺,李贺东.超高性能水泥基复合材料直接拉伸试验研究[J].土木工程学报,2009,42(9):32-41.
[4]MA H,LI V C.Tailoring engineered cementitious composites with local ingredients[J].Construction and Building Materials,2015(101):584-595.
[5]WANG S,LI V C.Engineered cementitious composites with highvolume fly ash[J].ACI Mater J,2007,104(3):233-241.
[6]PAN Z,WU C,LIU J.Study on mechanical properties of cost-effective polyvinyl alcohol engineered cementitious composites(PVA-ECC)[J].Construction and Building Materials,2015(78):397-404.
[7]YU J,et al.Strength improvement of strain-hardening cem-entitious composites with ultrahigh-volume fly ash[J].Journal of Materials in Civil Engineering,2017,29(9):05017003.
[8]XU A,SARKAR S L.Microstructural study of gypsum activated fly ash hydration in cement paste[J].Cement Concrete Research,1991(21):1137-1147.
[9]MA W,LIU C,BROWN P W,et al.Pore strutures of fly ashes activated by Ca(OH)2and CaSO4·2H2O[J].Cement Concrete Research,1995,25(2):417-425.
[10]POON C S,KOU S S,LAM L,et al.Activation of fly ash/cement systems using calcium sulfate anhydrite[J].Cement Concrete Research,2001(31):873-881.
[11]刘京红,史攀飞,杨跃飞,等.基于CT试验的混凝土裂纹扩展演化研究[J].混凝土,2017(4):74-77.
[12]玻璃纤维增强水泥性能试验方法抗弯性能:GB/T 15231-2008[S].中国标准出版社,1994.