复杂动荷载作用下全级配混凝土损伤机理细观数值试验
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摘要
提出了一种适用于复杂应力状态下的双折线弹性损伤模型,对混凝土试件进行了轴向拉压细观数值模拟试验,同时探讨了复杂应力状态下混凝土损伤破坏机理。然后基于实际工程采用的混凝土细观动态参数试验实测值,利用细观数值模型对循环荷载作用下全级配大坝混凝土试件进行了弯折损伤破坏模拟。其数值计算结果与材料试验测的数据吻合较好,进一步验证了在循环动荷载作用下预静载对动弯拉强度也存在强化现象。本文轴向拉压细观数值模拟试验表明,细观界面黏结强度是控制混凝土宏观抗压强度和宏观抗拉强度的关键参数,而黏结面泊松比的大小对混凝土宏观抗压强度影响很大。这个研究结果表明,混凝土材料受拉破坏机制与剪切破坏机制在本质上可统一为受拉破坏机制。
A bi-linear damage model is presented to study the mechanism of concrete fracturing under complicated stresses by numerical meso-simulations of axial tensile and compressive tests.The dynamic meso-strength and dynamic increase factor(DIF) of the mortar matrix,aggregate and their interfaces obtained by dynamic tensile tests are adopted to simulate the processes of flexural fracture of full-grade concrete specimens.The computational results agree well with the experiments,which show that static preloads also enhance the dynamic strengths under dynamic cyclical loads.This study shows that meso-interfacial strengths are key deterministic parameters to influence the compressive and tensile strengths of concrete,and the compressive strength is more strongly dependent on Poisson rates of the meso-interface than the tensile strength.This observation demonstrates that compressive and tensile mechanisms can be treated as a tensile mechanism in essence.
A bi-linear damage model is presented to study the mechanism of concrete fracturing under complicated stresses by numerical meso-simulations of axial tensile and compressive tests.The dynamic meso-strength and dynamic increase factor(DIF) of the mortar matrix,aggregate and their interfaces obtained by dynamic tensile tests are adopted to simulate the processes of flexural fracture of full-grade concrete specimens.The computational results agree well with the experiments,which show that static preloads also enhance the dynamic strengths under dynamic cyclical loads.This study shows that meso-interfacial strengths are key deterministic parameters to influence the compressive and tensile strengths of concrete,and the compressive strength is more strongly dependent on Poisson rates of the meso-interface than the tensile strength.This observation demonstrates that compressive and tensile mechanisms can be treated as a tensile mechanism in essence.
引文
[1]Loland K E.Continuous damage model for load-responseestimation of concrete[J].Cement and ConcreteResearch,1980,10(3):395-402
[2]于骁中.岩石和混凝土断裂力学[M].长沙:中南工业大学出版社,1991(Yu Xiaozhong,Fracture mechanics ofrock and concrete[M].Changsha:Central SouthUniversity of Technology Press,1991(in Chinese))
[3]Krajcinovic D.Continuum damage mechanics[J].Journalof Appled Mechanics Reviews,1984,37(1):1-6
[4]Mazars J.A description of micro-and macroscale damage ofconcrete structures[J].Engineering Fracture Mechanics,1986,25(5/6):729-737
[5]Resende L.A damage mechanics constitutive theory for theinelastic behaviour of concrete[J].Computer Methods inApplied Mechanics and Engineering,1987,60(1):57-93
[6]Faria R,Oliver J,Cervera M.A strain-based plasticviscous-damage model for massive concrete structures[J].International Journal of Solids and Structures,1998,35(14):1533-1558
[7]Simo J C,Ju J W.Strain-and stress-based continuumdamage models-I.formulation[J].International Journal ofSolids and Structures,1987,23(7):821-840
[8]Lee J,Fenves G L.Plastic-damage model for cyclic loadingof concrete structures[J].Journal of EngineeringMechanics,1998,124(8):892-900
[9]马怀发,陈厚群,周永发,等.大坝混凝土试件三维细观力学并行计算研究[J].工程力学,2007,24(10):74-79(Ma Huaifa,Chen Houqun,Zhou Yongfa,et al.Parallel computation study on 3D meso-mechanics of damconcrete[J].Engineering Mechanics,2007,24(10):74-79(in Chinese))
[10]马怀发,陈厚群,黎保琨.应变率效应对混凝土动弯拉强度的影响[J].水利学报,2005,36(1):69-76((MaHuaifa,Chen Houqun,Li Baokun.Influence of strain rateeffect on dynamic bending strength of concrete[J].Journalof Hydraulic Engineering,2005,36(1):69-76(inChinese))
[11]马怀发,陈厚群,黎保琨.混凝土试件细观结构的数值模拟[J].水利学报,2004,35(10):27-35(Ma Huaifa,Chen Houqun,Li Baokun.Meso-structure numericalsimulation of concrete specimens[J].Journal of HydraulicEngineering,2004,35(10):27-35(in Chinese))
[12]马怀发,陈厚群,吴建平,等.大坝混凝土三维细观力学数值模型研究[J].计算力学学报,2008,25(2):241-247(Ma Huaifa,Chen Houqun,Wu Jianping,et al.Studyon numerical algorithm of 3D meso-mechanics model of damconcrete[J].Chinese Journal of Computational Mechanics,2008,25(2):241-247(in Chinese))
[13]马怀发,陈厚群.全级配大坝混凝土动态损伤破坏机理研究及其细观力学分析方法[M].北京:中国水利水电出版社,2008
[14]陈改新.三峡工程大坝混凝土配合比的深化研究报告[R].北京:中国水利水电科学研究院,2009
[15]DL/T5150-2001水工混凝土试验规程[S].北京:中国电力出版社,2002(DL/T5150-2001Test code forhydraulic concrete[S].Beijing:China Electric PowerPress,2002(in Chinese))
[16]陈厚群,李德玉,马怀发,等.大岗山拱坝全级配混凝土地震动态抗力研究[R].北京:中国水利水电科学研究院,2010
[2]于骁中.岩石和混凝土断裂力学[M].长沙:中南工业大学出版社,1991(Yu Xiaozhong,Fracture mechanics ofrock and concrete[M].Changsha:Central SouthUniversity of Technology Press,1991(in Chinese))
[3]Krajcinovic D.Continuum damage mechanics[J].Journalof Appled Mechanics Reviews,1984,37(1):1-6
[4]Mazars J.A description of micro-and macroscale damage ofconcrete structures[J].Engineering Fracture Mechanics,1986,25(5/6):729-737
[5]Resende L.A damage mechanics constitutive theory for theinelastic behaviour of concrete[J].Computer Methods inApplied Mechanics and Engineering,1987,60(1):57-93
[6]Faria R,Oliver J,Cervera M.A strain-based plasticviscous-damage model for massive concrete structures[J].International Journal of Solids and Structures,1998,35(14):1533-1558
[7]Simo J C,Ju J W.Strain-and stress-based continuumdamage models-I.formulation[J].International Journal ofSolids and Structures,1987,23(7):821-840
[8]Lee J,Fenves G L.Plastic-damage model for cyclic loadingof concrete structures[J].Journal of EngineeringMechanics,1998,124(8):892-900
[9]马怀发,陈厚群,周永发,等.大坝混凝土试件三维细观力学并行计算研究[J].工程力学,2007,24(10):74-79(Ma Huaifa,Chen Houqun,Zhou Yongfa,et al.Parallel computation study on 3D meso-mechanics of damconcrete[J].Engineering Mechanics,2007,24(10):74-79(in Chinese))
[10]马怀发,陈厚群,黎保琨.应变率效应对混凝土动弯拉强度的影响[J].水利学报,2005,36(1):69-76((MaHuaifa,Chen Houqun,Li Baokun.Influence of strain rateeffect on dynamic bending strength of concrete[J].Journalof Hydraulic Engineering,2005,36(1):69-76(inChinese))
[11]马怀发,陈厚群,黎保琨.混凝土试件细观结构的数值模拟[J].水利学报,2004,35(10):27-35(Ma Huaifa,Chen Houqun,Li Baokun.Meso-structure numericalsimulation of concrete specimens[J].Journal of HydraulicEngineering,2004,35(10):27-35(in Chinese))
[12]马怀发,陈厚群,吴建平,等.大坝混凝土三维细观力学数值模型研究[J].计算力学学报,2008,25(2):241-247(Ma Huaifa,Chen Houqun,Wu Jianping,et al.Studyon numerical algorithm of 3D meso-mechanics model of damconcrete[J].Chinese Journal of Computational Mechanics,2008,25(2):241-247(in Chinese))
[13]马怀发,陈厚群.全级配大坝混凝土动态损伤破坏机理研究及其细观力学分析方法[M].北京:中国水利水电出版社,2008
[14]陈改新.三峡工程大坝混凝土配合比的深化研究报告[R].北京:中国水利水电科学研究院,2009
[15]DL/T5150-2001水工混凝土试验规程[S].北京:中国电力出版社,2002(DL/T5150-2001Test code forhydraulic concrete[S].Beijing:China Electric PowerPress,2002(in Chinese))
[16]陈厚群,李德玉,马怀发,等.大岗山拱坝全级配混凝土地震动态抗力研究[R].北京:中国水利水电科学研究院,2010
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