铺面水泥混凝土抗冻耐久性研究
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摘要
耐久性问题是水泥混凝土研究的重要课题之一。冻融对铺面混凝土使用寿命的影响非常大。冻融循环对混凝土强度的影响较为明显，随着冻融次数的增加，混凝土强度特性呈下降趋势。抗折强度反映最敏感，变化最快，下降幅度也最大。对铺面混凝土冻融破坏的评定指标进行了研究，提出仅以相对动弹性模量和质量变化率来衡量是不够的，应增加抗弯拉强度损失率这个指标。对于铺面混凝土采用普通冻融试验，相对动弹性模量和质量变化率两个指标过于宽松，应根据混凝土含气量情况分类重新界定。对于抗冻混凝土，相对动弹性模量判定指标定为80%，质量变化率指标定为1%。对于非抗冻混凝土，相对动弹性模量判定指标为60%，质量变化率指标为5%。综合现场气温资料和室内冻融温度循环特征，将现场混凝土经历的冻融循环次数在损伤等效意义下转化为等效的试验室冻融环境下的标准冻融循环次数,定义为等效室内冻融循环次数。利用等效冻融循环次数和标准冻融试验数据可近似地估计一个地区水泥混凝土冻融耐久性使用年限。建立了不同降温速率、不同降温区间动弹模量损失率0.4的冻融循环次数。冻结温度对混凝土的冻融破坏有明显的影响，冻结温度由-5℃降低到-10℃时，混凝土的冻融破坏效果将出现一个突变，也即当混凝土中最低冻结温度达-10℃时，冻融破坏的力量将明显加大，因此,对于混凝土冻结温度有可能到达-10℃或更低温度的建筑物，必须设计较高的混凝土抗冻标号。冻结速率对混凝土的冻融破坏有一定的影响，冻结速率提高，冻融破坏力加大，混凝土容易破坏。应用混凝土冻融损伤模型，理论计算得到铺面混凝土抗冻标号与自然冻融循环次数之间定量对应关系为1:14的数量级，参考室内外对比试验结果及考虑一定安全系数，取铺面混凝土抗冻标号与自然冻融循环次数之间的定量对应关系为1:14。
It is one of the important problems to study of cement concrete durability. Freezing andthawing of concrete affects pavement life in much large degrees. There is evidently influencethat freezing and thawing cycling to concrete strength. Concrete strength decreases withfreezing and thawing cycling times. Flexural strength is a mostly sensitive parameter varyingrapidly and largely. Being not efficient only with relative dynamic elastic modulus and masschanging rate, a parameter was discussed in which to appraise the damage degrees of concreteas freezing and thawing. The losing rate of flexural strength parameter should be used inappraising concrete freezing and thawing property. For pavement concrete freezing andthawing test，the parameters of relative dynamic elastic modulus and mass changing rate aretoo loose, so it should be determined again based on concrete air volume. For freezingresistant concrete, the limit of relative dynamic elastic modulus should be80%and masschanging rate1%. For common concrete, the limit of relative dynamic elastic modulus shouldbe60%and mass changing rate5%. Based on site and laboratory condition, freezing andthawing cycling times of concrete in site was changed to equivalent cycling times inlaboratory environment which was named as equivalent freezing and thawing cycle times.Servicing life of concrete in freezing and thawing may be estimated based on the equivalentfreezing and thawing cycle times and laboratory test data. It was been set up that the freezingand thawing times when dynamic elastic modulus losing by40%. There is evident influencethat freezing temperature to concrete damage. There is an abruptly change for concretefreezing and thawing damage effect when freezing temperature falls from-5℃to-10℃.Freezing and thawing damage force would be much great when temperature falling to-10℃.For construction concrete would endure freezing temperature lower than-10℃, the highfreezing-resistant grade concrete should be used in design. There is an influence betweentemperature decreasing rates to concrete freezing damage. Concrete would be badly damagedwhen temperature decreasing rapidly. Based on concrete freezing and thawing damagingmodel, relation between resistance grade to freezing-thawing of pavement concrete andnatural freezing and thawing cycle times was calculated out which is about1:14. Based onlaboratory and site test result and a certain safety factor,1:14was chosen as the quantityrelation.
It is one of the important problems to study of cement concrete durability. Freezing andthawing of concrete affects pavement life in much large degrees. There is evidently influencethat freezing and thawing cycling to concrete strength. Concrete strength decreases withfreezing and thawing cycling times. Flexural strength is a mostly sensitive parameter varyingrapidly and largely. Being not efficient only with relative dynamic elastic modulus and masschanging rate, a parameter was discussed in which to appraise the damage degrees of concreteas freezing and thawing. The losing rate of flexural strength parameter should be used inappraising concrete freezing and thawing property. For pavement concrete freezing andthawing test，the parameters of relative dynamic elastic modulus and mass changing rate aretoo loose, so it should be determined again based on concrete air volume. For freezingresistant concrete, the limit of relative dynamic elastic modulus should be80%and masschanging rate1%. For common concrete, the limit of relative dynamic elastic modulus shouldbe60%and mass changing rate5%. Based on site and laboratory condition, freezing andthawing cycling times of concrete in site was changed to equivalent cycling times inlaboratory environment which was named as equivalent freezing and thawing cycle times.Servicing life of concrete in freezing and thawing may be estimated based on the equivalentfreezing and thawing cycle times and laboratory test data. It was been set up that the freezingand thawing times when dynamic elastic modulus losing by40%. There is evident influencethat freezing temperature to concrete damage. There is an abruptly change for concretefreezing and thawing damage effect when freezing temperature falls from-5℃to-10℃.Freezing and thawing damage force would be much great when temperature falling to-10℃.For construction concrete would endure freezing temperature lower than-10℃, the highfreezing-resistant grade concrete should be used in design. There is an influence betweentemperature decreasing rates to concrete freezing damage. Concrete would be badly damagedwhen temperature decreasing rapidly. Based on concrete freezing and thawing damagingmodel, relation between resistance grade to freezing-thawing of pavement concrete andnatural freezing and thawing cycle times was calculated out which is about1:14. Based onlaboratory and site test result and a certain safety factor,1:14was chosen as the quantityrelation.
引文
[1]龚洛书，柳春圃.混凝土的耐久性及其防护修补[M].北京：中国建筑工业出版设，1990
[2]POWERS T C.A working hypothesis for further studies of frost resistance ofconcrete[J].Journal of the American Concrete Institute，1945，16(4)：245–272.
[3]POWERS T C. The air requirement of frost-resistant concrete[C]//Proceedings of theHighway Research Board Annual Meeting. Washington D.C.，USA：[s.n.]，1949：184–211.
[4]Power T C.Void spacing as a basis for producing air-entrained concrete.ACI Journal,Proceedings,1954,50(9):741-760
[5]POWERS T C，HELMUTH R A. Theory of volume changes in hardened Portland cement pastesduring freezing[C]//Proceedings of the Highway Research Board Annual Meeting.Washington， D.C.， USA：[s.n.]，1953：285–297.
[6]Gonnerman H F.Test of concrete containing air-entraining portland cements or air-entrainingadded to batch at mixer.Proceeding, American concerete Institute,1944,45:149-150
[7]American Society for Test and Material.C457-90.Standard test method for microscopicaldetermination of parameters of the air-void system in hardened concrete.1990
[8]Pigeon M,Lachance M.Critical air void spacing factor for concretes submitted to slowfreeze-thaw cycle.ACI Journal,1981,78(4):282-291
[9]Pigeon M.Freeze-thaw durability versus freezing rate.ACI Journal,1985,82:684-692
[10]Backstrom,James E.Origin,evolution,and effects of the air void system inconcrete.Part2-Influence of type and amount of air-entraining agent.ACI Journal,1958:261-272
[11]Malhotra,V M.Mechanical properties and freezing and thawing resistance ofnon-air-entrained,air-entained,and air-entained superplasticized concrete using ASTM TestC666,Procedures A and B.Cement,Concrete,and Aggregates,1982:3-23
[12]Chatterji S.Aspect of the freezing process in a porous materials-water system Part I: freezingand the properties of water and ice.Cement and Concrete Research,199929(4):627-630
[13]Chatterji S.Aspect of the freezing process in a porous materials-water system Part II: freezingand the properties of frozen porous materials.Cement and Concrete Research1999,29(6):781-784
[14]Bager D H.Ice formation in hardened cement paste,part I-room temperature cured paste withvariable moisture contents.Cement and Concrete Research,1986,16(5):709-720
[15]Bager D H.Ice formation in hardened cement paste,part II-drying and resaturation on roomtemperature cured paste.Cement and Concrete Research,1986,16(5):835-844
[16]中华人民共和国行业标准.《公路工程水泥与水泥混凝土试验规程》（JTG E30-2005）.北京：人民交通出版社，2005
[17]中华人民共和国行业标准.《公路水泥混凝土路面施工技术规范》（JTG F30-2003）.北京：人民交通出版社，2003
[18]唐光普，刘西拉，施士升.冻融条件下混凝土破坏面演化模型研究[J].岩石力学与工程学报，2006，25(12)：2572–2578.
[19]唐光普，刘西拉.基于唯象损伤观点的混凝土冻害模型研究[J].四川建筑科学研究，2007，33(3)：138–143.
[20]中华人民共和国国家标准.《普通混凝土长期性能和耐久性能试验方法标准》（GB/T50082-2009）.北京：中国建筑工业出版社，2009.
[21]李晔.铺面水泥混凝土抗冻设计指标研究[D].博士学位论文，上海：同济大学，2003
[22]Barry J. Dempsey, W. Andrew Herlache, and Arti J. Patel. Climatic-Materials-StructuralPavement Analysis Program. Transportation Research Record1095.
[23]李金玉，邓正刚，曹建国等.混凝土抗冻性的定量化设计.载：重点工程混凝土耐久性的研究与工程应用[M].北京：中国建材工业出版社，2000.
[24]中华人民共和国行业标准.公路钢筋混凝土及预应力混凝土设计规范（JTG D62-2004）[S].北京：中国交通出版社，2004.
[25]覃丽坤，宋玉普，陈浩然等.双轴拉压混凝土在冻融循环后的力学性能及破坏准则[J].岩石力学与工程学报，2005，24（10）：1740-1745.
[26]蔡四维，蔡敏.混凝土的损伤断裂[M].北京：人民交通出版社，1999.
[27]蔡昊.混凝土抗冻耐久性预测模型[博士学位论文][D].北京：清华大学，1998.
[28]张士萍，邓敏，吴建华等.孔结构对混凝土抗冻性的影响[J].武汉理工大学学报，2008，30(6)：56–59.
[29]陈立军.混凝土孔径尺寸对其使用寿命的影响[J].武汉理工大学学报,2007,29(6):50-53
[30] CRC Handbook of Chemistry and Physics,70thEdition. CRC Press,1989-1990.
[31]李金玉，曹建国，徐文雨等.混凝土冻融破坏机理的研究[J].水利学报，1999，(1)：41–49.
[32]Pigeon M.Freeze-thaw durability versus freezing rate.ACI Journal,1985,82:684-692
[33]Backstrom,James E.Origin,evolution,and effects of the air void system inconcrete.Part2-Influence of type and amount of air-entraining agent.ACI Journal,1958:261-272
[34]Malhotra,V M.Mechanical properties and freezing and thawing resistance ofnon-air-entrained,air-entained,and air-entained superplasticized concrete using ASTM TestC666,Procedures A and B.Cement,Concrete,and Aggregates,1982:3-23
[35]Chatterji S.Aspect of the freezing process in a porous materials-water system Part I: freezingand the properties of water and ice.Cement and Concrete Research,199929(4):627-630
[36]Chatterji S.Aspect of the freezing process in a porous materials-water system Part II: freezingand the properties of frozen porous materials.Cement and Concrete Research1999,29(6):781-784
[37]Bager D H.Ice formation in hardened cement paste,part I-room temperature cured paste withvariable moisture contents.Cement and Concrete Research,1986,16(5):709-720
[38]Bager D H.Ice formation in hardened cement paste,part II-drying and resaturation on roomtemperature cured paste.Cement and Concrete Research,1986,16(5):835-844
[39]Donald J.Janssen. Moisture in Portland Cement Concrete. Transportation Research Record1121.
[40]Barry J. Dempsey, W. Andrew Herlache, and Arti J. Patel. Climatic Materials StructuralPavement Analysis Program. Transportation Research Record1095.
[41]吴中伟,廉惠珍.高性能混凝土[M].北京:中国铁道出版社,1999.
[42] CRC Handbook of Chemistry and Physics,70thEdition. CRC Press,1989-1990.
[43]刘西拉，唐光普.现场环境下混凝土冻融耐久性预测方法研究[J].岩石力学与工程学报，2007，26(12)：2412–2419.
[44] Donald J. Janssen. Moisture in Portland Cement Concrete. Transportation Research Record1121.
[45]中华人民共和国行业标准.水运工程混凝土试验规程（JTJ270-98）[S].北京：中国交通出版社，1998.
[46]Bjorn Johannesson. Dimensional and ice content changes of hardened concrete at differentfreezing and thawing temperature. Cement and Concrete composites32(2010):73-83
[47]B.Zuber, J.Marchand. Modeling the deterioration of hydrated cement systems exposed to frostaction.Cement and Concrete Research30(2000):1929-1939
[48]Ke-fei LI,Qiang ZENG. Influence of freezing rate on cryo-damage of cementitious material.Journal of Zhejiang University SCIENCE A.2009,10(1):17-21
[2]POWERS T C.A working hypothesis for further studies of frost resistance ofconcrete[J].Journal of the American Concrete Institute，1945，16(4)：245–272.
[3]POWERS T C. The air requirement of frost-resistant concrete[C]//Proceedings of theHighway Research Board Annual Meeting. Washington D.C.，USA：[s.n.]，1949：184–211.
[4]Power T C.Void spacing as a basis for producing air-entrained concrete.ACI Journal,Proceedings,1954,50(9):741-760
[5]POWERS T C，HELMUTH R A. Theory of volume changes in hardened Portland cement pastesduring freezing[C]//Proceedings of the Highway Research Board Annual Meeting.Washington， D.C.， USA：[s.n.]，1953：285–297.
[6]Gonnerman H F.Test of concrete containing air-entraining portland cements or air-entrainingadded to batch at mixer.Proceeding, American concerete Institute,1944,45:149-150
[7]American Society for Test and Material.C457-90.Standard test method for microscopicaldetermination of parameters of the air-void system in hardened concrete.1990
[8]Pigeon M,Lachance M.Critical air void spacing factor for concretes submitted to slowfreeze-thaw cycle.ACI Journal,1981,78(4):282-291
[9]Pigeon M.Freeze-thaw durability versus freezing rate.ACI Journal,1985,82:684-692
[10]Backstrom,James E.Origin,evolution,and effects of the air void system inconcrete.Part2-Influence of type and amount of air-entraining agent.ACI Journal,1958:261-272
[11]Malhotra,V M.Mechanical properties and freezing and thawing resistance ofnon-air-entrained,air-entained,and air-entained superplasticized concrete using ASTM TestC666,Procedures A and B.Cement,Concrete,and Aggregates,1982:3-23
[12]Chatterji S.Aspect of the freezing process in a porous materials-water system Part I: freezingand the properties of water and ice.Cement and Concrete Research,199929(4):627-630
[13]Chatterji S.Aspect of the freezing process in a porous materials-water system Part II: freezingand the properties of frozen porous materials.Cement and Concrete Research1999,29(6):781-784
[14]Bager D H.Ice formation in hardened cement paste,part I-room temperature cured paste withvariable moisture contents.Cement and Concrete Research,1986,16(5):709-720
[15]Bager D H.Ice formation in hardened cement paste,part II-drying and resaturation on roomtemperature cured paste.Cement and Concrete Research,1986,16(5):835-844
[16]中华人民共和国行业标准.《公路工程水泥与水泥混凝土试验规程》（JTG E30-2005）.北京：人民交通出版社，2005
[17]中华人民共和国行业标准.《公路水泥混凝土路面施工技术规范》（JTG F30-2003）.北京：人民交通出版社，2003
[18]唐光普，刘西拉，施士升.冻融条件下混凝土破坏面演化模型研究[J].岩石力学与工程学报，2006，25(12)：2572–2578.
[19]唐光普，刘西拉.基于唯象损伤观点的混凝土冻害模型研究[J].四川建筑科学研究，2007，33(3)：138–143.
[20]中华人民共和国国家标准.《普通混凝土长期性能和耐久性能试验方法标准》（GB/T50082-2009）.北京：中国建筑工业出版社，2009.
[21]李晔.铺面水泥混凝土抗冻设计指标研究[D].博士学位论文，上海：同济大学，2003
[22]Barry J. Dempsey, W. Andrew Herlache, and Arti J. Patel. Climatic-Materials-StructuralPavement Analysis Program. Transportation Research Record1095.
[23]李金玉，邓正刚，曹建国等.混凝土抗冻性的定量化设计.载：重点工程混凝土耐久性的研究与工程应用[M].北京：中国建材工业出版社，2000.
[24]中华人民共和国行业标准.公路钢筋混凝土及预应力混凝土设计规范（JTG D62-2004）[S].北京：中国交通出版社，2004.
[25]覃丽坤，宋玉普，陈浩然等.双轴拉压混凝土在冻融循环后的力学性能及破坏准则[J].岩石力学与工程学报，2005，24（10）：1740-1745.
[26]蔡四维，蔡敏.混凝土的损伤断裂[M].北京：人民交通出版社，1999.
[27]蔡昊.混凝土抗冻耐久性预测模型[博士学位论文][D].北京：清华大学，1998.
[28]张士萍，邓敏，吴建华等.孔结构对混凝土抗冻性的影响[J].武汉理工大学学报，2008，30(6)：56–59.
[29]陈立军.混凝土孔径尺寸对其使用寿命的影响[J].武汉理工大学学报,2007,29(6):50-53
[30] CRC Handbook of Chemistry and Physics,70thEdition. CRC Press,1989-1990.
[31]李金玉，曹建国，徐文雨等.混凝土冻融破坏机理的研究[J].水利学报，1999，(1)：41–49.
[32]Pigeon M.Freeze-thaw durability versus freezing rate.ACI Journal,1985,82:684-692
[33]Backstrom,James E.Origin,evolution,and effects of the air void system inconcrete.Part2-Influence of type and amount of air-entraining agent.ACI Journal,1958:261-272
[34]Malhotra,V M.Mechanical properties and freezing and thawing resistance ofnon-air-entrained,air-entained,and air-entained superplasticized concrete using ASTM TestC666,Procedures A and B.Cement,Concrete,and Aggregates,1982:3-23
[35]Chatterji S.Aspect of the freezing process in a porous materials-water system Part I: freezingand the properties of water and ice.Cement and Concrete Research,199929(4):627-630
[36]Chatterji S.Aspect of the freezing process in a porous materials-water system Part II: freezingand the properties of frozen porous materials.Cement and Concrete Research1999,29(6):781-784
[37]Bager D H.Ice formation in hardened cement paste,part I-room temperature cured paste withvariable moisture contents.Cement and Concrete Research,1986,16(5):709-720
[38]Bager D H.Ice formation in hardened cement paste,part II-drying and resaturation on roomtemperature cured paste.Cement and Concrete Research,1986,16(5):835-844
[39]Donald J.Janssen. Moisture in Portland Cement Concrete. Transportation Research Record1121.
[40]Barry J. Dempsey, W. Andrew Herlache, and Arti J. Patel. Climatic Materials StructuralPavement Analysis Program. Transportation Research Record1095.
[41]吴中伟,廉惠珍.高性能混凝土[M].北京:中国铁道出版社,1999.
[42] CRC Handbook of Chemistry and Physics,70thEdition. CRC Press,1989-1990.
[43]刘西拉，唐光普.现场环境下混凝土冻融耐久性预测方法研究[J].岩石力学与工程学报，2007，26(12)：2412–2419.
[44] Donald J. Janssen. Moisture in Portland Cement Concrete. Transportation Research Record1121.
[45]中华人民共和国行业标准.水运工程混凝土试验规程（JTJ270-98）[S].北京：中国交通出版社，1998.
[46]Bjorn Johannesson. Dimensional and ice content changes of hardened concrete at differentfreezing and thawing temperature. Cement and Concrete composites32(2010):73-83
[47]B.Zuber, J.Marchand. Modeling the deterioration of hydrated cement systems exposed to frostaction.Cement and Concrete Research30(2000):1929-1939
[48]Ke-fei LI,Qiang ZENG. Influence of freezing rate on cryo-damage of cementitious material.Journal of Zhejiang University SCIENCE A.2009,10(1):17-21