考虑孔隙影响的混凝土有效弹性模量预测分析研究
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摘要
本文通过纳米压痕实验技术得到混凝土材料细观各相参数,基于渐进均匀化理论,采用蒙特卡洛方法和双向游走方法建立了含孔隙混凝土的胞元模型.分析了孔隙在冻融循环次数增加情况下对混凝土有效弹性模量的影响,同时与有限元模拟分析进行了比较.结果表明:随着冻融循环次数增加,孔隙体积分数增大,界面与砂浆压痕模量相对降低,但对骨料影响较小,导致混凝土宏观弹性模量随之降低;理论分析预测的混凝土有效弹性模量与有限元模拟结果吻合良好.应用含孔隙混凝土胞元模型能有效地预测混凝土宏观弹性模量,进而也为其在冻融作用下老化演变机理的研究评估提供了基础.
In this paper, a cell model of porous concrete is established using Monte Carlo simulation and a bidirectional walk method. By using nanoindentation technique, the microscopic mechanical properties of each phase of concrete are obtained. The asymptotic homogenization theory is then used to predict the effective modulus of elasticity of concrete and evaluate the effect of pores with increasing freeze-thaw cycles, in comparison with numerical finite element analysis. The results show that as the volume fraction of pores increases due to increased freeze-thaw cycles, the indentation moduli of the interface and mortar decrease obviously and the one of aggregate seldom changes, resulting in the decrease of macroscopic modulus of elasticity of concrete. The theoretical analysis results are in good agreement with finite element simulation. The cell model of porous concrete is effective in predicting the modulus of elasticity of concrete, and it paves the foundation for evaluating aging mechanism of concrete under freeze-thaw actions.
In this paper, a cell model of porous concrete is established using Monte Carlo simulation and a bidirectional walk method. By using nanoindentation technique, the microscopic mechanical properties of each phase of concrete are obtained. The asymptotic homogenization theory is then used to predict the effective modulus of elasticity of concrete and evaluate the effect of pores with increasing freeze-thaw cycles, in comparison with numerical finite element analysis. The results show that as the volume fraction of pores increases due to increased freeze-thaw cycles, the indentation moduli of the interface and mortar decrease obviously and the one of aggregate seldom changes, resulting in the decrease of macroscopic modulus of elasticity of concrete. The theoretical analysis results are in good agreement with finite element simulation. The cell model of porous concrete is effective in predicting the modulus of elasticity of concrete, and it paves the foundation for evaluating aging mechanism of concrete under freeze-thaw actions.
引文
[1]HSU T T C,SLATE F O,STURMAN G M,et al.Micro-cracking of plain concrete and the shape of the stress-strain curve[J].ACI Materials Journal,1963,60(2):209-224.
[2]曹秀丽,曹志翔,喻骁.冻融循环对混凝土质量损失及相对动弹模量影响的试验研究[J].铁道建筑,2013,3:125-127.
[3]YANG Z,WEISS W J,OLEK J.Water transport in concrete damaged by tensile loading and freeze-thaw cycling[J].Journal of Materials in Civil Engineering,2006,18(3):424-434.
[4]胡更开,郑泉水,黄筑平.复合材料有效弹性性质分析方法[J].力学进展,2001,31(3):361-393.
[5]ZHENG Q S,DU D X.An explicit and universally applicable estimate for the effective properties of multiphase composites which accounts for inclusion distribution[J].Journal of the Mechanics and Physics of Solids,2001,49(11):2765-2788.
[6]杜修力,金浏.考虑孔隙及微裂纹影响的混凝土宏观力学特性研究[J].工程力学,2012,29(8):101-107.
[7]LIONS J L,PAPANICOLAOU G,BENSOUSSAN A.Asymptotic analysis for periodic structures[M].North-Holland:Elsevier,1978.
[8]GUEDES J M,KIKUCHI N.Preprocessing and postprocessing for materials based on the homogenization method with adaptive finite element methods[J].Computer Methods in Applied Mechanics and Engineering,1990,83(2):143-198.
[9]HASSANI B,HINTON E.A review of homogenization and topology optimizationⅡ-analytical and numerical solution of homogenization equations[J].Computers and Structures,1998,69:719-738.
[10]LI Y Y,CUI J Z.The multi-scale computational method for the mechanics parameters of the materials with random distribution of multi-scale grains[J].Composites Science and Technology,2005,65(9):1447-1458.
[11]刘美华,李鸿琦,王静,等.纳米压痕测量精度的影响因素[J].机械工程材料,2008,32(8):4-7.
[12]赵素晶,孙伟.纳米压痕在水泥基材料中的应用与研究进展[J].硅酸盐学报,2011,39(1):164-176.
[13]NEMECEK J.Creep effects in nanoindentation of hydrated phases cement pastes[J].Mater Charact,2009,60(9):1028-1034.
[14]苏建君,江五贵,黎军顽,等.纳米压痕试验中圆柱形压头尺寸效应[J].南昌航空大学学报:自然科学版,2007,21(4):78-82.
[15]唐欣薇.基于宏细观力学的混凝土破损行为研究[D].北京:清华大学,2009.
[16]黄沃成,陈正,梁伟英,等.混凝土圆形骨料随机投放的双向游走法[J].混凝土,2016,4:103-106.
[17]QIAO P,MCLEAN D I,CHEN F.Concrete performance using low-degradation aggregates[R].Olympia:Washington(State)Department of Transportation,Office of Research and Library Services,2012.
[18]LUO Q,LIU D X,QIAO P,et al.Microstructural damage characterization of concrete under freeze-thaw action[J].International Journal of Damage Mechanics,2018,27(10):1551-1568.
[19]SCRIVENER K L.Backscattered electron imaging of cementitious microstructures:understanding and quantification[J].Cement and Concrete Composites,2004,26(8):935-945.
[2]曹秀丽,曹志翔,喻骁.冻融循环对混凝土质量损失及相对动弹模量影响的试验研究[J].铁道建筑,2013,3:125-127.
[3]YANG Z,WEISS W J,OLEK J.Water transport in concrete damaged by tensile loading and freeze-thaw cycling[J].Journal of Materials in Civil Engineering,2006,18(3):424-434.
[4]胡更开,郑泉水,黄筑平.复合材料有效弹性性质分析方法[J].力学进展,2001,31(3):361-393.
[5]ZHENG Q S,DU D X.An explicit and universally applicable estimate for the effective properties of multiphase composites which accounts for inclusion distribution[J].Journal of the Mechanics and Physics of Solids,2001,49(11):2765-2788.
[6]杜修力,金浏.考虑孔隙及微裂纹影响的混凝土宏观力学特性研究[J].工程力学,2012,29(8):101-107.
[7]LIONS J L,PAPANICOLAOU G,BENSOUSSAN A.Asymptotic analysis for periodic structures[M].North-Holland:Elsevier,1978.
[8]GUEDES J M,KIKUCHI N.Preprocessing and postprocessing for materials based on the homogenization method with adaptive finite element methods[J].Computer Methods in Applied Mechanics and Engineering,1990,83(2):143-198.
[9]HASSANI B,HINTON E.A review of homogenization and topology optimizationⅡ-analytical and numerical solution of homogenization equations[J].Computers and Structures,1998,69:719-738.
[10]LI Y Y,CUI J Z.The multi-scale computational method for the mechanics parameters of the materials with random distribution of multi-scale grains[J].Composites Science and Technology,2005,65(9):1447-1458.
[11]刘美华,李鸿琦,王静,等.纳米压痕测量精度的影响因素[J].机械工程材料,2008,32(8):4-7.
[12]赵素晶,孙伟.纳米压痕在水泥基材料中的应用与研究进展[J].硅酸盐学报,2011,39(1):164-176.
[13]NEMECEK J.Creep effects in nanoindentation of hydrated phases cement pastes[J].Mater Charact,2009,60(9):1028-1034.
[14]苏建君,江五贵,黎军顽,等.纳米压痕试验中圆柱形压头尺寸效应[J].南昌航空大学学报:自然科学版,2007,21(4):78-82.
[15]唐欣薇.基于宏细观力学的混凝土破损行为研究[D].北京:清华大学,2009.
[16]黄沃成,陈正,梁伟英,等.混凝土圆形骨料随机投放的双向游走法[J].混凝土,2016,4:103-106.
[17]QIAO P,MCLEAN D I,CHEN F.Concrete performance using low-degradation aggregates[R].Olympia:Washington(State)Department of Transportation,Office of Research and Library Services,2012.
[18]LUO Q,LIU D X,QIAO P,et al.Microstructural damage characterization of concrete under freeze-thaw action[J].International Journal of Damage Mechanics,2018,27(10):1551-1568.
[19]SCRIVENER K L.Backscattered electron imaging of cementitious microstructures:understanding and quantification[J].Cement and Concrete Composites,2004,26(8):935-945.
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