基于温度应力试验机试验的混凝土早期抗裂性研究
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摘要
混凝土早期由于自身水化等因素产生膨胀或收缩,变形受到约束时,便产生约束内应力,而混凝土早期强度低,内应力超过混凝土抗拉强度便产生微裂缝,这种承载前的裂缝对结构的耐久性产生极坏的影响。影响混凝土早期开裂的因素多,并且错综复杂,因此迫切需要能将混凝土性能量化的试验方法和综合的评价指标,优化混凝土配比设计,以提高混凝土的抗裂性。
本文在研究国内外温度应力试验机的基础上,改进温度应力试验机在混凝土开裂试验方面的性能,通过多组单项性能调试试验和四组完整的混凝土开裂试验,改善了温度应力试验机温度、位移以及应力测试和控制方面的性能,成功地实现了水循环控制混凝土环境温度,并能使混凝土试件的温度较好的模拟实际工程中的温度历程。
本文利用大型有限元分析软件ANSYS进行混凝土早期温度应力场的计算,计算结果与温度应力试验机试验结合,优化混凝土抗裂性的评价和研究体系。为了验证模型建立的合理性,本文将绝热状态下的有限元温度场结果与文献中的经典结论对照,对比了模型绝热温升与试验绝热温升数据;分析了温度应力试验机试件不同位置应力随时间变化的规律,验证了夹头部位的应力集中现象。
最后,总结了本文存在的问题和需进一步开展的工作,为混凝土早期开裂评价体系的建立和温度应力试验机试验方法标准化提供了参考。
Bases on the hydration of the concrete, the shrinkage or the expand comes into being at early age. If the shrinkage (or the expand) was restricted, internal stresses would be occurred in the concrete. And the concrete would crack at the time of the internal stress bigger than the tensile strength. This kind of non-structural crack does great harm for the durability of concrete. Factors which lead to the crack of concrete are various and most of them are act or react on each other. So in order to get the most appropriate concrete which has batter cracking resistance, The testing method which can quantify the property of concrete and the aggregative indicator which can evaluate the cracking resistance of concrete are important and necessary objects to study.
Based on the study of the temperature-stress testing machine allover the world, this paper improved the equipment to make the results tested by TSTM more accurate. Teams of test which study the individual performance and four groups of integrate concrete cracking test have been put up, to improved temperature, displacement and stress testing and performance control of the temperature stress testing machine. Success in achieving the water cycle control temperature of concrete and concrete specimens can better simulate actual engineering course of the temperature of different parts.
In order to verify the reasonableness of the model, the paper compared finite element results under adiabatic temperature field with the classic Conclusion: compared the adiabatic temperature rise of the experiment with the model adiabatic temperature data; analysis the development of stress in different place of temperature-stress testing machine, which can explain the stress concentration at the fixed collet.
Finally, the existing shortages in this paper were indicated and the research direction in the future was put forward. The content and conclusions of this paper may provide a reference for evaluative system of cracking resistance of early age concrete, also for the standardization of the test of temperature-stress testing machine.
本文在研究国内外温度应力试验机的基础上,改进温度应力试验机在混凝土开裂试验方面的性能,通过多组单项性能调试试验和四组完整的混凝土开裂试验,改善了温度应力试验机温度、位移以及应力测试和控制方面的性能,成功地实现了水循环控制混凝土环境温度,并能使混凝土试件的温度较好的模拟实际工程中的温度历程。
本文利用大型有限元分析软件ANSYS进行混凝土早期温度应力场的计算,计算结果与温度应力试验机试验结合,优化混凝土抗裂性的评价和研究体系。为了验证模型建立的合理性,本文将绝热状态下的有限元温度场结果与文献中的经典结论对照,对比了模型绝热温升与试验绝热温升数据;分析了温度应力试验机试件不同位置应力随时间变化的规律,验证了夹头部位的应力集中现象。
最后,总结了本文存在的问题和需进一步开展的工作,为混凝土早期开裂评价体系的建立和温度应力试验机试验方法标准化提供了参考。
Bases on the hydration of the concrete, the shrinkage or the expand comes into being at early age. If the shrinkage (or the expand) was restricted, internal stresses would be occurred in the concrete. And the concrete would crack at the time of the internal stress bigger than the tensile strength. This kind of non-structural crack does great harm for the durability of concrete. Factors which lead to the crack of concrete are various and most of them are act or react on each other. So in order to get the most appropriate concrete which has batter cracking resistance, The testing method which can quantify the property of concrete and the aggregative indicator which can evaluate the cracking resistance of concrete are important and necessary objects to study.
Based on the study of the temperature-stress testing machine allover the world, this paper improved the equipment to make the results tested by TSTM more accurate. Teams of test which study the individual performance and four groups of integrate concrete cracking test have been put up, to improved temperature, displacement and stress testing and performance control of the temperature stress testing machine. Success in achieving the water cycle control temperature of concrete and concrete specimens can better simulate actual engineering course of the temperature of different parts.
In order to verify the reasonableness of the model, the paper compared finite element results under adiabatic temperature field with the classic Conclusion: compared the adiabatic temperature rise of the experiment with the model adiabatic temperature data; analysis the development of stress in different place of temperature-stress testing machine, which can explain the stress concentration at the fixed collet.
Finally, the existing shortages in this paper were indicated and the research direction in the future was put forward. The content and conclusions of this paper may provide a reference for evaluative system of cracking resistance of early age concrete, also for the standardization of the test of temperature-stress testing machine.
引文
[1]朱伯芳.大体积混凝土温度应力与温度控制.北京,中国电力出版社,1999
[2]刘数华,方坤河等.混凝土抗裂评价指标综述.混凝土,2004,175(5):32-33
[3]李光伟.混凝土抗裂性指标及人工骨料混凝土抗裂能力评价.四川水力发电,2000,19(2):67-69
[4]孙永波,曾力等.大体积混凝土抗裂性指标试验研究.大坝与安全,2003:32-35
[5]马丽媛,姚燕,田培等.国内外混凝土收缩性能及抗裂性试验研究方法评述.中国建材科技,2001,1:27-31
[6] R.Springenschmid. Prevention of Thermal Cracking in Concrete at Early ages. E&FN SPON, 1998
[7] ?.Bj?ntegaard, T.A. Hammer and E.J. Sellevold. Cracking in High Performance Concrete before Setting. Internaional Symposium on High-Performance and Reactive Powder Concrete, Canada, 1998: 1-17
[8] Grzybowski, M., and Shah, S. P. Model to predict cracking in fiber reinforced concrete due to restrained shrinkage. Magazine of Concrete Research (London), 1989, 41(148): 125-135
[9] Grzybowski, M., and Shah, S. P. Shrinkage cracking of fiber reinforced concrete. ACI Material Journal, 1990, 187(2): 138-148
[10] W.Jason Weiss et al. Shrinkage Cracking Potntial, Permeability, and Strength for HPC: Influence of W/C, Silica Fume, Latex, and Shrinkage Reducing Admixtures. Internaional Symposium on High-Performance and Reactive Powder Concrete, Canada , 349-364
[11]张士海.胶凝体系对混凝土早期开裂的影响与评价方法研究[硕士学位论文],北京,清华大学,2002
[12] Soroushian P, Marza F,Alhozaimy A. Plastic shrinkage cracking of PP fiber reinforced concrete. ACI Mater. J, 1995, 92(5): 553-560
[13] RILEM TC119-TCE:Avoidance of Thermal Cracking in Concrete at Early Ages , 1993
[14] R.Springenschmid. Development of the cracking frame and the temperature-stress testing machine. Thermal cracking in concrete at early ages, London, Chapman&Hall, 1995: 137-144
[15] Kolver, K.,Testing System for Determining the Mechanical Behavior of Early Age Concrete under Restrained and FreeUniaxial Shrinkage. Materials and Structure, 1994, 27: 324-330
[16] Penev,D. and Kawamura, M. A Laboratory Device for Restrained Shrinkage Fracture of Soil-Cement Mixture, Materials and Structure, 1992, 25: 115-120
[17]林志海.混凝土早期开裂试验评价研究[硕士学位论文],北京,清华大学土木工程系建筑材料研究所,2002
[18]张国志,屠柳青,夏卫华.混凝土早期开裂评价指标研究.混凝土,2005,187(5): 14-19
[19]张涛,混凝土早期开裂敏感性的影响因素研究[博士学位论文],北京,清华大学土木工程系,2006
[20]张士海,覃维祖,张涛,林志海.混凝土早期抗裂性能评价-单轴约束试验方法的进展.混凝土与水泥制品,2002,3:13-16
[21] Zhihai LIN. Quantitative Evaluation of the Effectiveness of Expansive Concretes as a Countermeasure for Thermal Cracking and the Development of its Practical Application[D]. Tokyo, Japan, Department of Civil Engineering of the University of Tokyo, 2006, 9
[22]任朝志.温度一应力试验机温湿度控制系统设计[硕士学位论文],武汉,武汉理工大学自动化学院,2007
[23]林训杰.温度一应力试验机试件裂纹图象识别系统设计[硕士学位论文].武汉,武汉理工大学自动化学院,2007
[24] M. Kalimur Rahman, Mohammed H. Baluch, and Ali H. Al-Gadhib. Modeling of Shrinkage and Creep Stresses in Concrete Repair. ACI materials journal, 1999, 96(5): 542-551
[25]张子明,冯树荣,石青春等.基于等效时间的混凝土绝热温升.河海大学学报,2004,32(5):573-577
[26]张子明,周红军,殷波.基于等效时间的混凝土徐变.河海大学学报,2005,33(2):173-176
[27] Yingshu Yuan, Guo Li, and Yue Cai. Modeling for prediction of restrained shrinkage effect in concrete repair. Cement and concrete research, 2003, 33: 347-352
[28] Pipat Termkhajornkit, Toyoharu Nawa, Masashi Nakai. Effect of fly ash on autogenous shrinkage[J]. Cement and Concrete Research, 2005, 35, 473-482
[29]李骁春.高层建筑地下室侧墙温度裂缝机理及控制技术[硕士学位论文],南京,河海大学土木工程学院,2004
[30]吕建福,汪东杰,巴恒静.大体积混凝土早期温度发展规律及温度控制.混凝土,198(4),23-25
[31]胡盛华,覃维祖.环境温度对早期混凝土墙体温度场的影响.工业建筑,2005,35(10):54-57
[32]夏少武.活化能及其计算,北京,高等教育出版社,1999
[33] Z. P. Bazant. Thermo-viscoelasity of Aging Concrete[J]. Journal of Engineering Mechanics, 1974, 100(6): 575-597
[34] Copeland and Verbeck. Chemistry of Hydration of Porland Cement, Proceedings of Fourth International Symposium on the Chemistry of Cement, Washington, D. C, 1960: 14-16
[35]李光伟.玄武岩人工骨料混凝土抗裂性能试验研究.水电站设计,2001, 17(1):77-80
[36]王铁梦.工程结构裂缝控制,北京,中国建筑工业出版社,1997
[37]申屠宪民.钢筋混凝土水池温度应力计算.化工设计,1998,1:31-34
[38] N. J. Carino and H. S. Lew. The Maturity Method: From Theory of Application, NIST, Gaithersburg, MD, 2001
[39] CEB-FIP Model Code 1990. ComitéEuro-International du Beton, Bulletin D information No.213/214, Tomas Telford, 1993: 473
[40] Trost H. Auswirkungen des Superpositionsprinzips auf Kriech- und Relaxations probleme bei Beton Spannbeton. Beron und Stahlbau, 1967, 62: 230-238
[41] Bazant Z. P. and Panula L. Practical Prediction of Time Dependent Defotmation of Concrete[J]. Materials and Structures, PartⅠandⅡ, 1978, 11(65): 307-328;ⅢandⅣ, 1978, 11(66): 415-434;ⅤandⅥ, 1979, 12(69): 169-173
[2]刘数华,方坤河等.混凝土抗裂评价指标综述.混凝土,2004,175(5):32-33
[3]李光伟.混凝土抗裂性指标及人工骨料混凝土抗裂能力评价.四川水力发电,2000,19(2):67-69
[4]孙永波,曾力等.大体积混凝土抗裂性指标试验研究.大坝与安全,2003:32-35
[5]马丽媛,姚燕,田培等.国内外混凝土收缩性能及抗裂性试验研究方法评述.中国建材科技,2001,1:27-31
[6] R.Springenschmid. Prevention of Thermal Cracking in Concrete at Early ages. E&FN SPON, 1998
[7] ?.Bj?ntegaard, T.A. Hammer and E.J. Sellevold. Cracking in High Performance Concrete before Setting. Internaional Symposium on High-Performance and Reactive Powder Concrete, Canada, 1998: 1-17
[8] Grzybowski, M., and Shah, S. P. Model to predict cracking in fiber reinforced concrete due to restrained shrinkage. Magazine of Concrete Research (London), 1989, 41(148): 125-135
[9] Grzybowski, M., and Shah, S. P. Shrinkage cracking of fiber reinforced concrete. ACI Material Journal, 1990, 187(2): 138-148
[10] W.Jason Weiss et al. Shrinkage Cracking Potntial, Permeability, and Strength for HPC: Influence of W/C, Silica Fume, Latex, and Shrinkage Reducing Admixtures. Internaional Symposium on High-Performance and Reactive Powder Concrete, Canada , 349-364
[11]张士海.胶凝体系对混凝土早期开裂的影响与评价方法研究[硕士学位论文],北京,清华大学,2002
[12] Soroushian P, Marza F,Alhozaimy A. Plastic shrinkage cracking of PP fiber reinforced concrete. ACI Mater. J, 1995, 92(5): 553-560
[13] RILEM TC119-TCE:Avoidance of Thermal Cracking in Concrete at Early Ages , 1993
[14] R.Springenschmid. Development of the cracking frame and the temperature-stress testing machine. Thermal cracking in concrete at early ages, London, Chapman&Hall, 1995: 137-144
[15] Kolver, K.,Testing System for Determining the Mechanical Behavior of Early Age Concrete under Restrained and FreeUniaxial Shrinkage. Materials and Structure, 1994, 27: 324-330
[16] Penev,D. and Kawamura, M. A Laboratory Device for Restrained Shrinkage Fracture of Soil-Cement Mixture, Materials and Structure, 1992, 25: 115-120
[17]林志海.混凝土早期开裂试验评价研究[硕士学位论文],北京,清华大学土木工程系建筑材料研究所,2002
[18]张国志,屠柳青,夏卫华.混凝土早期开裂评价指标研究.混凝土,2005,187(5): 14-19
[19]张涛,混凝土早期开裂敏感性的影响因素研究[博士学位论文],北京,清华大学土木工程系,2006
[20]张士海,覃维祖,张涛,林志海.混凝土早期抗裂性能评价-单轴约束试验方法的进展.混凝土与水泥制品,2002,3:13-16
[21] Zhihai LIN. Quantitative Evaluation of the Effectiveness of Expansive Concretes as a Countermeasure for Thermal Cracking and the Development of its Practical Application[D]. Tokyo, Japan, Department of Civil Engineering of the University of Tokyo, 2006, 9
[22]任朝志.温度一应力试验机温湿度控制系统设计[硕士学位论文],武汉,武汉理工大学自动化学院,2007
[23]林训杰.温度一应力试验机试件裂纹图象识别系统设计[硕士学位论文].武汉,武汉理工大学自动化学院,2007
[24] M. Kalimur Rahman, Mohammed H. Baluch, and Ali H. Al-Gadhib. Modeling of Shrinkage and Creep Stresses in Concrete Repair. ACI materials journal, 1999, 96(5): 542-551
[25]张子明,冯树荣,石青春等.基于等效时间的混凝土绝热温升.河海大学学报,2004,32(5):573-577
[26]张子明,周红军,殷波.基于等效时间的混凝土徐变.河海大学学报,2005,33(2):173-176
[27] Yingshu Yuan, Guo Li, and Yue Cai. Modeling for prediction of restrained shrinkage effect in concrete repair. Cement and concrete research, 2003, 33: 347-352
[28] Pipat Termkhajornkit, Toyoharu Nawa, Masashi Nakai. Effect of fly ash on autogenous shrinkage[J]. Cement and Concrete Research, 2005, 35, 473-482
[29]李骁春.高层建筑地下室侧墙温度裂缝机理及控制技术[硕士学位论文],南京,河海大学土木工程学院,2004
[30]吕建福,汪东杰,巴恒静.大体积混凝土早期温度发展规律及温度控制.混凝土,198(4),23-25
[31]胡盛华,覃维祖.环境温度对早期混凝土墙体温度场的影响.工业建筑,2005,35(10):54-57
[32]夏少武.活化能及其计算,北京,高等教育出版社,1999
[33] Z. P. Bazant. Thermo-viscoelasity of Aging Concrete[J]. Journal of Engineering Mechanics, 1974, 100(6): 575-597
[34] Copeland and Verbeck. Chemistry of Hydration of Porland Cement, Proceedings of Fourth International Symposium on the Chemistry of Cement, Washington, D. C, 1960: 14-16
[35]李光伟.玄武岩人工骨料混凝土抗裂性能试验研究.水电站设计,2001, 17(1):77-80
[36]王铁梦.工程结构裂缝控制,北京,中国建筑工业出版社,1997
[37]申屠宪民.钢筋混凝土水池温度应力计算.化工设计,1998,1:31-34
[38] N. J. Carino and H. S. Lew. The Maturity Method: From Theory of Application, NIST, Gaithersburg, MD, 2001
[39] CEB-FIP Model Code 1990. ComitéEuro-International du Beton, Bulletin D information No.213/214, Tomas Telford, 1993: 473
[40] Trost H. Auswirkungen des Superpositionsprinzips auf Kriech- und Relaxations probleme bei Beton Spannbeton. Beron und Stahlbau, 1967, 62: 230-238
[41] Bazant Z. P. and Panula L. Practical Prediction of Time Dependent Defotmation of Concrete[J]. Materials and Structures, PartⅠandⅡ, 1978, 11(65): 307-328;ⅢandⅣ, 1978, 11(66): 415-434;ⅤandⅥ, 1979, 12(69): 169-173