超高性能混凝土圆环约束收缩试验研究
|
摘要
以约束水平、环境条件(密闭或干燥)和钢纤维等为参数,开展了超高性能混凝土(UHPC)圆环约束收缩试验。研究了钢环应变随龄期的发展规律;分析了各参数对圆环约束下的残余应力与各关键龄期的力学性能的影响;采用了拉应力水平和应力松弛率来评价UHPC的开裂性能。为配合圆环收缩试验,开展了自由收缩与基本力学性能试验。试验表明,未掺钢纤维的UHPC早期开裂风险大,在14 d前均发生开裂,裂缝平均宽度大于0.25 mm,含钢纤维试件均未开裂。不同约束程度对拉应力水平与应力松弛率的影响均显著,降低约束程度能有效降低开裂风险。与自由收缩测试结果不同,圆环约束UHPC在密闭条件下后期的开裂风险会高于环向干燥条件。建议以密闭条件下14 d的抗裂性能作为控制指标评价圆环约束下UHPC的开裂性能。
Shrinkage of ultra-high performance concrete(UHPC) was investigated by restrained ring tests taking the restraint degree, sealed or dry circumferential condition and steel fiber as the main parameters. The development of steel ring strain with age was studied. The influences of various parameters on the residual stress under the restrained ring and the mechanical property at key age were analyzed. The tensile stress level and the relaxation rate were used to evaluate the cracking performance of UHPC. Free shrinkage and mechanical properties were also investigated to match the restrained ring test. The results showed a high early cracking risk of UHPC without steel fiber. All specimens cracked with an average width of more than 0.25 mm before 14 d, while the specimens with steel fiber did not crack. Various restraint degrees all have significant effects on both the tensile stress level and stress relaxation rate, indicating that decreasing the restraint degree can reduce the cracking risk effectively. Different from the free shrinkage test results, UHPC under ring restraint showed higher cracking risk at the late stage in a sealed condition than in a dry circumferential condition. The crack resistance at 14 d under a sealed condition is recommended as a control index to evaluate the cracking performance of UHPC under restrained ring.
Shrinkage of ultra-high performance concrete(UHPC) was investigated by restrained ring tests taking the restraint degree, sealed or dry circumferential condition and steel fiber as the main parameters. The development of steel ring strain with age was studied. The influences of various parameters on the residual stress under the restrained ring and the mechanical property at key age were analyzed. The tensile stress level and the relaxation rate were used to evaluate the cracking performance of UHPC. Free shrinkage and mechanical properties were also investigated to match the restrained ring test. The results showed a high early cracking risk of UHPC without steel fiber. All specimens cracked with an average width of more than 0.25 mm before 14 d, while the specimens with steel fiber did not crack. Various restraint degrees all have significant effects on both the tensile stress level and stress relaxation rate, indicating that decreasing the restraint degree can reduce the cracking risk effectively. Different from the free shrinkage test results, UHPC under ring restraint showed higher cracking risk at the late stage in a sealed condition than in a dry circumferential condition. The crack resistance at 14 d under a sealed condition is recommended as a control index to evaluate the cracking performance of UHPC under restrained ring.
引文
[1]陈宝春,季韬,黄卿维,等.超高性能混凝土研究综述[J]建筑科学与工程学报,2014,31(3):1―24.Chen Baochun,Ji Tao,Huang Qingwei,et al.Review of research on ultra-high performance concrete[J].Journal of Architecture and Civil Engineering,2014,31(3):1―24.(in Chinese)
[2]陈宝春,李聪,黄伟,等.超高性能混凝土收缩综述[J].交通运输工程学报,2018,18(1):13―28.Chen Baochun,Li Cong,Huang Wei,et al.Review of ultra-high performance concrete shrinkage[J].Journal of Traffic and Transportation Engineering,2018,18(1):13―28.(in Chinese)
[3]刘君平,徐帅,陈宝春.钢-UHPC组合梁与钢-普通混凝土组合梁抗弯性能对比试验研究[J].工程力学,2018,35(11):92―98,145.Liu Junping,Xu Shuai,Chen Baochun.Experimental study on flexural behaviors of steel-UHPC composite girder and steel-conventional concrete composite girder[J].Engineering Mechanics,2018,35(11):92―98,145.(in Chinese)
[4]孙启力,路新瀛,聂鑫,等.非蒸养UHPC-钢板结构界面的受拉和剪切性能试验研究[J].工程力学,2017,34(9):167―174,192.Sun Qili,Lu Xinying,Nie Xin,et al.Experimental research on tensile and shear behavior of tensile and shear behavior of the interface between non steam cured UHPC and steel plate structure[J].Engineering Mechanics,2017,34(9):167―174,192.(in Chinese)
[5]张文华,张云升,陈振宇.超高性能混凝土抗缩比钻地弹侵彻试验及数值仿真[J].工程力学,2018,35(7):167―175,186.Zhang Wenhua,Zhang Yunsheng,Chen Zhenyu.Penetration test and numerical simulation of ultra-high performance concrete with a scaled earth penetrator[J].Engineering Mechanics,2018,35(7):167―175,186.(in Chinese)
[6]Jun K P,Seung H P,Dong J K.Eect of matrix shrinkage on rate sensitivity of the pullout response of smooth steel fibers in ultra-high-performance concrete[J].Cement and Concrete Composites,2018,94:226―237.
[7]Xie T,Fang C,Mohamad Ali M S,et al.Characterizations of autogenous and drying shrinkage of ultra-high performance concrete(UHPC):An experimental study[J].Cement and Concrete Composites,2018,91:156―237.
[8]Yoo D Y,Park J J,Kim S W,et al.Influence of ring size on the restrained shrinkage behavior of ultra high performance fiber reinforced concrete[J].Materials&Structures,2014,47(7):1161―1174.
[9]陈瑜,张起森.水泥混凝土早期抗裂性能的研究现状[J].建筑材料学报,2004,7(4):411―417.Chen Yu,Zhang Qisen.Review of study on cement concrete cracking resistance at early ages[J].Journal of Building Materials,2004,7(4):411―417.(in Chinese)
[10]Park J J,Yoo D Y,Kim S W,et al.Drying shrinkage cracking characteristics of ultra-high-performance fiber reinforced concrete with expansive and shrinkage reducing agents[J].Magazine of Concrete Research,2013,65(4):248―256.
[11]Ji T,Chen C Y,Chen Y Y,et al.Effect of moisture state of recycled fine aggregate on the cracking resistibility of concrete[J].Construction&Building Materials,2013,44:726―733.
[12]马新伟,李学英,朱卫中,等.部分约束条件下中低水灰比混凝土开裂的预测[J].建筑材料学报,2006,9(5):598―602.Ma Xinwei,Li Xueying,Zhu Weihzhong,et al.Study on early autogenous shrinkage of ultra high performance cementitous composite[J].Journal of Building Materials,2009,9(5):598―602.(in Chinese)
[13]Weiss W J,Shah S P.Restrained shrinkage cracking:The role of shrinkage reducing admixtures and specimen geometry[J].Materials&Structures,2002,35(2):85―91.
[14]Hossain A B,Weiss J.Assessing residual stress development and stress relaxation in restrained concrete ring specimens[J].Cement&Concrete Composites,2004,26(5):531―540.
[15]Hossain A B,Weiss J.The role of specimen geometry and boundary conditions on stress development and cracking in the restrained ring test[J].Cement&Concrete Research,2006,36(1):189―199.
[16]Briffaut M,Benboudjema F,Torrenti J M,et al.Athermal active restrained shrinkage ring test to study the early age concrete behaviour of massive structures[J].Cement&Concrete Research,2011,41(1):56―63.
[17]郑建岚,王国杰,王辉明.自密实混凝土自生约束收缩开裂性能试验研究[J].建筑材料学报,2010,13(5):607―612.Zheng Jianlan,Wang Guojie,Wang Huiming.Experimental study on cracking tendency under restrained autogenous shrinkage of self-compacting concrete[J].Journal of Building Materials,2010,13(5):607―612.(in Chinese)
[18]王国杰.自密实混凝土圆环约束收缩试验研究[J].工程力学,2014,31(12):173―180.Wang Guojie.Experimental study on restrained shrinkage of self-compacting concrete by ring test[J].Engineering Mechanics,2014,31(12):173―180.(in Chinese)
[19]王俊颜,边晨,肖汝诚,等.常温养护型超高性能混凝土的圆环约束收缩性能[J].材料导报,2017,31(23):52―57.Wang Junyan,Bian Chen,Xiao Rucheng,et al.Restrained shrinkage behavior of ultra high performance concrete without thermal curing[J].Materials Review,2017,31(23):52―57.(in Chinese)
[20]韩松,刘丹,张戈,等.超低水胶比复合胶凝材料孔结构随养护制度和龄期的变化机理[J].硅酸盐学报,2017,45(11):1594―1604.Han Song,Liu Dan,Zhang Ge,et al.Mechanism of curing effect on pore structure of hardened cementitious composites with ultra-low water to binder ratio[J].Journal of the Chinese Ceramic Society,2017,45(11):1594―1604.(in Chinese)
[21]Ba H,Su A,Gao X,et al.Cracking tendency of restrained concrete at early ages[J].Journal of Wuhan University of Technology(Material Science Edition).2008,23(2):263―267.
[22]Oesterlee C,Sadouki H,Brühwiler E.Structural analysis of a composite bridge combining UHPFRC and reinforced concrete[C]//Proceedings of the 2nd International Symposium on Ultra High Performance Concrete,Ed.,Fehling E,Schmidt M,Stürwald S.Kassel,Germany:Kassel University Press,2008:647―654.
[23]吴林妹,史才军,张祖华,等.钢纤维对超高性能混凝土干燥收缩的影响[J].材料导报.2017,31(12):58―65.Wu Linmei,Shi Caijun,Zhang Zuhua,et al.Effects of steel fiber on drying shrinkage of ultrahigh performance concrete[J].Materials Review,2017,31(12):58―65.(in Chinese)
[24]罗霞,韦建刚,李聪,等.密闭条件下UHPC的收缩性能试验研究[J].应用基础与工程科学学报,2018,26(4):830―842.Luo Xia,Wei Jiangang,Li Cong,et al.Experimental investigations of the shrinkage behavior of sealed UHPC[J].Journal of Basic Science and Engineering,2018,26(4):830―842.(in Chinese)
[25]Soren E,Christoph M.Autogenous shrinkage strain of ultra high performance concrete(UHPC)[C]//Proceeding of the 2nd International Symposium on Ultra High Performance Concrete.Kassel,Germany:Kassel University Press,2008:433―441.
[26]曹世勇.超高性能水泥基复合材料自收缩特性及其机理研究[J].硅酸盐通报,2015,34(3):813―818,823.Cao Shiyong.Study on autogenous shrinkage characteristic and mechanism of ultra-high performance cementitous composite[J].Bulletin of the Chinese Ceramic Society,2015,34(3):813―818,823.(in Chinese)
[27]ASTM C 1581―04,Standard test method for determining age at cracking and induced tensile stress characteristics of mortar and concrete under restrained shrinkage[S].West Conshohocken,PA,USA:ASTM,2004.
[28]GB/T 50082―2009,普通混凝土长期性能和耐久性能试验方法标准[S].北京:中国标准出版社,2009.GB/T 50082―2009,Standard for test method of long-term performance and durability of ordinary concrete[S].Beijing:Standards Press of China,2009.(in Chinese)
[29]GB/T 31387―2015,活性粉末混凝土[S].北京:中国标准出版社,2015.GB/T 31387―2015,Reactive powder concrete[S].Beijing:Standards Press of China,2015.(in Chinese)
[30]GB/T 50081―2002,普通混凝土力学性能试验方法[S].北京:中国标准出版社,2002.GB/T 50081―2002,Standard for test method of mechanical properties on ordinary concrete[S].Beijing:Standards Press of China,2002.(in Chinese)
[31]Hannawi K,Bian H,Prince-Agbodjan W,et al.Effect of different types of fibers on the microstructure and the mechanical behavior of ultra-high performance fiber-reinforced concretes[J].Composites Part B:Engineering,2016,86:214―220.
[2]陈宝春,李聪,黄伟,等.超高性能混凝土收缩综述[J].交通运输工程学报,2018,18(1):13―28.Chen Baochun,Li Cong,Huang Wei,et al.Review of ultra-high performance concrete shrinkage[J].Journal of Traffic and Transportation Engineering,2018,18(1):13―28.(in Chinese)
[3]刘君平,徐帅,陈宝春.钢-UHPC组合梁与钢-普通混凝土组合梁抗弯性能对比试验研究[J].工程力学,2018,35(11):92―98,145.Liu Junping,Xu Shuai,Chen Baochun.Experimental study on flexural behaviors of steel-UHPC composite girder and steel-conventional concrete composite girder[J].Engineering Mechanics,2018,35(11):92―98,145.(in Chinese)
[4]孙启力,路新瀛,聂鑫,等.非蒸养UHPC-钢板结构界面的受拉和剪切性能试验研究[J].工程力学,2017,34(9):167―174,192.Sun Qili,Lu Xinying,Nie Xin,et al.Experimental research on tensile and shear behavior of tensile and shear behavior of the interface between non steam cured UHPC and steel plate structure[J].Engineering Mechanics,2017,34(9):167―174,192.(in Chinese)
[5]张文华,张云升,陈振宇.超高性能混凝土抗缩比钻地弹侵彻试验及数值仿真[J].工程力学,2018,35(7):167―175,186.Zhang Wenhua,Zhang Yunsheng,Chen Zhenyu.Penetration test and numerical simulation of ultra-high performance concrete with a scaled earth penetrator[J].Engineering Mechanics,2018,35(7):167―175,186.(in Chinese)
[6]Jun K P,Seung H P,Dong J K.Eect of matrix shrinkage on rate sensitivity of the pullout response of smooth steel fibers in ultra-high-performance concrete[J].Cement and Concrete Composites,2018,94:226―237.
[7]Xie T,Fang C,Mohamad Ali M S,et al.Characterizations of autogenous and drying shrinkage of ultra-high performance concrete(UHPC):An experimental study[J].Cement and Concrete Composites,2018,91:156―237.
[8]Yoo D Y,Park J J,Kim S W,et al.Influence of ring size on the restrained shrinkage behavior of ultra high performance fiber reinforced concrete[J].Materials&Structures,2014,47(7):1161―1174.
[9]陈瑜,张起森.水泥混凝土早期抗裂性能的研究现状[J].建筑材料学报,2004,7(4):411―417.Chen Yu,Zhang Qisen.Review of study on cement concrete cracking resistance at early ages[J].Journal of Building Materials,2004,7(4):411―417.(in Chinese)
[10]Park J J,Yoo D Y,Kim S W,et al.Drying shrinkage cracking characteristics of ultra-high-performance fiber reinforced concrete with expansive and shrinkage reducing agents[J].Magazine of Concrete Research,2013,65(4):248―256.
[11]Ji T,Chen C Y,Chen Y Y,et al.Effect of moisture state of recycled fine aggregate on the cracking resistibility of concrete[J].Construction&Building Materials,2013,44:726―733.
[12]马新伟,李学英,朱卫中,等.部分约束条件下中低水灰比混凝土开裂的预测[J].建筑材料学报,2006,9(5):598―602.Ma Xinwei,Li Xueying,Zhu Weihzhong,et al.Study on early autogenous shrinkage of ultra high performance cementitous composite[J].Journal of Building Materials,2009,9(5):598―602.(in Chinese)
[13]Weiss W J,Shah S P.Restrained shrinkage cracking:The role of shrinkage reducing admixtures and specimen geometry[J].Materials&Structures,2002,35(2):85―91.
[14]Hossain A B,Weiss J.Assessing residual stress development and stress relaxation in restrained concrete ring specimens[J].Cement&Concrete Composites,2004,26(5):531―540.
[15]Hossain A B,Weiss J.The role of specimen geometry and boundary conditions on stress development and cracking in the restrained ring test[J].Cement&Concrete Research,2006,36(1):189―199.
[16]Briffaut M,Benboudjema F,Torrenti J M,et al.Athermal active restrained shrinkage ring test to study the early age concrete behaviour of massive structures[J].Cement&Concrete Research,2011,41(1):56―63.
[17]郑建岚,王国杰,王辉明.自密实混凝土自生约束收缩开裂性能试验研究[J].建筑材料学报,2010,13(5):607―612.Zheng Jianlan,Wang Guojie,Wang Huiming.Experimental study on cracking tendency under restrained autogenous shrinkage of self-compacting concrete[J].Journal of Building Materials,2010,13(5):607―612.(in Chinese)
[18]王国杰.自密实混凝土圆环约束收缩试验研究[J].工程力学,2014,31(12):173―180.Wang Guojie.Experimental study on restrained shrinkage of self-compacting concrete by ring test[J].Engineering Mechanics,2014,31(12):173―180.(in Chinese)
[19]王俊颜,边晨,肖汝诚,等.常温养护型超高性能混凝土的圆环约束收缩性能[J].材料导报,2017,31(23):52―57.Wang Junyan,Bian Chen,Xiao Rucheng,et al.Restrained shrinkage behavior of ultra high performance concrete without thermal curing[J].Materials Review,2017,31(23):52―57.(in Chinese)
[20]韩松,刘丹,张戈,等.超低水胶比复合胶凝材料孔结构随养护制度和龄期的变化机理[J].硅酸盐学报,2017,45(11):1594―1604.Han Song,Liu Dan,Zhang Ge,et al.Mechanism of curing effect on pore structure of hardened cementitious composites with ultra-low water to binder ratio[J].Journal of the Chinese Ceramic Society,2017,45(11):1594―1604.(in Chinese)
[21]Ba H,Su A,Gao X,et al.Cracking tendency of restrained concrete at early ages[J].Journal of Wuhan University of Technology(Material Science Edition).2008,23(2):263―267.
[22]Oesterlee C,Sadouki H,Brühwiler E.Structural analysis of a composite bridge combining UHPFRC and reinforced concrete[C]//Proceedings of the 2nd International Symposium on Ultra High Performance Concrete,Ed.,Fehling E,Schmidt M,Stürwald S.Kassel,Germany:Kassel University Press,2008:647―654.
[23]吴林妹,史才军,张祖华,等.钢纤维对超高性能混凝土干燥收缩的影响[J].材料导报.2017,31(12):58―65.Wu Linmei,Shi Caijun,Zhang Zuhua,et al.Effects of steel fiber on drying shrinkage of ultrahigh performance concrete[J].Materials Review,2017,31(12):58―65.(in Chinese)
[24]罗霞,韦建刚,李聪,等.密闭条件下UHPC的收缩性能试验研究[J].应用基础与工程科学学报,2018,26(4):830―842.Luo Xia,Wei Jiangang,Li Cong,et al.Experimental investigations of the shrinkage behavior of sealed UHPC[J].Journal of Basic Science and Engineering,2018,26(4):830―842.(in Chinese)
[25]Soren E,Christoph M.Autogenous shrinkage strain of ultra high performance concrete(UHPC)[C]//Proceeding of the 2nd International Symposium on Ultra High Performance Concrete.Kassel,Germany:Kassel University Press,2008:433―441.
[26]曹世勇.超高性能水泥基复合材料自收缩特性及其机理研究[J].硅酸盐通报,2015,34(3):813―818,823.Cao Shiyong.Study on autogenous shrinkage characteristic and mechanism of ultra-high performance cementitous composite[J].Bulletin of the Chinese Ceramic Society,2015,34(3):813―818,823.(in Chinese)
[27]ASTM C 1581―04,Standard test method for determining age at cracking and induced tensile stress characteristics of mortar and concrete under restrained shrinkage[S].West Conshohocken,PA,USA:ASTM,2004.
[28]GB/T 50082―2009,普通混凝土长期性能和耐久性能试验方法标准[S].北京:中国标准出版社,2009.GB/T 50082―2009,Standard for test method of long-term performance and durability of ordinary concrete[S].Beijing:Standards Press of China,2009.(in Chinese)
[29]GB/T 31387―2015,活性粉末混凝土[S].北京:中国标准出版社,2015.GB/T 31387―2015,Reactive powder concrete[S].Beijing:Standards Press of China,2015.(in Chinese)
[30]GB/T 50081―2002,普通混凝土力学性能试验方法[S].北京:中国标准出版社,2002.GB/T 50081―2002,Standard for test method of mechanical properties on ordinary concrete[S].Beijing:Standards Press of China,2002.(in Chinese)
[31]Hannawi K,Bian H,Prince-Agbodjan W,et al.Effect of different types of fibers on the microstructure and the mechanical behavior of ultra-high performance fiber-reinforced concretes[J].Composites Part B:Engineering,2016,86:214―220.