模拟酸雨腐蚀下预应力混凝土梁的抗弯性能研究
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摘要
为了探讨酸雨腐蚀环境对预应力混凝土梁抗弯性能的影响,制作了8根预应力混凝土梁,从混凝土强度等级、预应力度和钢绞线腐蚀率等方面,进行8根预应力混凝土梁的三分点静载试验。试验结果及分析表明,混凝土强度对屈服后试验梁的抗弯性能影响较大,对弹性阶段的刚度影响较小;随着预应力度的增加,试验梁的开裂荷载逐渐增大,进入裂缝阶段后,刚度下降速度逐渐加快;钢绞线腐蚀率越大,试验梁的极限抗弯承载力越低;腐蚀率在一定范围内(>3.22%),随着腐蚀率的增大,预应力混凝土梁试件的开裂弯矩、屈服弯矩和极限弯矩明显降低。根据试验结果,提出了模拟酸雨环境下预应力混凝土梁试件抗弯承载力的计算方法,同时采用ANSYS软件对预应力混凝土梁进行非线性有限元分析,将试验梁的计算值和模拟值与试验值进行比较,均吻合较好。
In order to investigate the influence of acid rain environment on the flexural behavior of prestressed concrete beams,eight prestressed concrete beams were fabricated.They were subjected to three-point bending tests to investigate the concrete strength grade,prestressing ratio and corrosion rate of steel strand.The experimental results and analysis indicate that the strength of concrete has a great influence on the flexural behavior of post-yielding beams,but has little effect on the stiffness of the post-yielding beams;with the increase of prestressing force,the cracking load of the beams gradually increases; after entering into the fracture stage,the rate of stiffness decrease gradually increases; the greater the corrosion rate of steel strand,the lower the ultimate bending capacity of the test beams; within the a certain range(>3.22%),with increasing corrosion rate,the effects of corrosion have a significant impact on the cracking moment,the yield moment and the ultimate moment.Based on the test results,the paper puts forward the formula to predict the flexural capacity of prestressed concrete beams in acid rain corrosion environment;in addition,nonlinear finite element analysis of prestressed concrete beams was conducted in ANSYS software.The experimental results of the test beams are in good agreement with the calculated results and the simulation results.
In order to investigate the influence of acid rain environment on the flexural behavior of prestressed concrete beams,eight prestressed concrete beams were fabricated.They were subjected to three-point bending tests to investigate the concrete strength grade,prestressing ratio and corrosion rate of steel strand.The experimental results and analysis indicate that the strength of concrete has a great influence on the flexural behavior of post-yielding beams,but has little effect on the stiffness of the post-yielding beams;with the increase of prestressing force,the cracking load of the beams gradually increases; after entering into the fracture stage,the rate of stiffness decrease gradually increases; the greater the corrosion rate of steel strand,the lower the ultimate bending capacity of the test beams; within the a certain range(>3.22%),with increasing corrosion rate,the effects of corrosion have a significant impact on the cracking moment,the yield moment and the ultimate moment.Based on the test results,the paper puts forward the formula to predict the flexural capacity of prestressed concrete beams in acid rain corrosion environment;in addition,nonlinear finite element analysis of prestressed concrete beams was conducted in ANSYS software.The experimental results of the test beams are in good agreement with the calculated results and the simulation results.
引文
[1] 冯大斌.预应力技术回顾与展望[J].建筑科学,2013,29(11):30-38.(FENG Da-bin.Past and future of prestressing technologies [J].Building Science,2013,29(11):30-38.(in Chinese))
[2] Podolny Jr W.Corrosion of prestressing steels and its mitigation[J].PCI Journal,1992,37(5):34-35.
[3] 吴雪峰.锈蚀钢绞线力学性能和粘结性能研究[D].中南大学,2014.(WU Xue -feng.Research on Mechanical Properties and Bonding Performance of Corroded Prestressing Steel Strand[D].Central South University,2014.(in Chinese))
[4] 张新民,柴发合,王淑兰,等.中国酸雨研究现状[J].环境科学研究,2010,23(5):527-532.(ZHANG Xin-min,CHAI Fa-he,WANG Shu-lan,et al.Research progress of acid precipitation in China[J].Research of Environmental Sciences,2010,23(5):527-532.(in Chinese))
[5] 李富民,邓天慈,王江浩,等.预应力混凝土结构耐久性研究综述[J].建筑科学与工程学报,2015,32(2):1-20.(LI Fu-min,DENG Tian-ci,WANG Jiang-hao,et al.Review of research on durability of prestressed concrete structures[J].Journal of Architecture and Civil Engineering,2015,32(2):1-20.(in Chinese))
[6] 杨枫,薛伟辰.高预应力度混凝土梁抗震性能探讨[J].地震工程与工程振动,2006,26(6):108-113.(YANG Feng,XUE Wei-chen.Studies on seismic performance of prestressed concrete beams with high PPR[J].Earthquake Engineering and Engineering Vibration,2006,26(6):108-113.(in Chinese))
[7] 范颖芳,周晶.受腐蚀钢筋混凝土构件受力性能研究现状[J].土木工程学报,2004,37(7):23-28.(FAN Ying-fang,ZHOU Jing.State of the art load bearing property of corroded reinforced concrete members[J].China Civil Engineering Journal,2004,37(7):23-28.(in Chinese))
[8] Rodriguez J,Ortega L M,Casal J.Load carrying capacity of concrete structures with corroded reinforcement[J].Construction and Building Materials,1997,11(4):239-248.
[9] 曾严红,顾祥林,张伟平,等.混凝土中钢筋加速锈蚀方法探讨[J].结构工程师,2009,25(1):101-105.(ZENG Yan-hong,GU Xiang-lin,ZHANG Wei-ping,et al.Accelerated corrosion technique for reinforcement steel bars in concrete[J].Structural Engineers,2009,25(1):101-105.(in Chinese))
[10] Darmawan M S,Stewart M G.Spatial time -dependent reliability analysis of corroding pretensioned prestressed concrete bridge girders [J].Structural Sa-fety,2007,29(1):16-31.
[11] 陈梦成,罗晶,许开成.江西省酸雨特征分析及预测模型[J].环境科学与技术,2014,37(10):167-170.(CHEN Meng-cheng,LUO Jing,XU Kai-cheng.Characteristics and prediction model of Jiangxi acid rain[J].Environmental Science & Technology,2014,37(10):167-170.(in Chinese))
[12] 余芳.钢绞线腐蚀后的部分预应力混凝土梁受力性能研究[D].大连理工大学,2013.(YU Fang.Study on Mechanical Performance of Partial Prestressed Concrete Beams with Corroded Strand[D].Dalian University of Technology,2013.(in Chinese))
[13] 李富民,袁迎曙,王波,等.腐蚀钢绞线预应力混凝土梁受弯承载力评估[J].建筑结构学报,2011,32(2):10-16.(LI Fu-min,YUAN Ying-shu,WANG Bo,et al.Evaluation on flexural strength of prestressed concrete beams with corroded steel strands[J].Journal of Building Structures,2011,32(2):10-16.(in Chinese))
[14] Hognestad E.Study of Combined Bending and Axial Load in Reinforced Concrete Member [R].University of Illinois at Urbana Champaign,1951.
[15] 毛伟,贾金青,余芳.分离模型预应力混凝土梁数值模拟[J].铁道建筑,2011(7):17-19.(MAO Wei,JIA Jin-qing,YU Fang.Numerical simulation of prestressed concrete beams with separation model[J].Railway Engineering,2011(7):17-19.(in Chinese))
[16] 张耀庭,邱继生.ANSYS在预应力钢筋混凝土结构非线性分析中的应用[J].华中科技大学学报(城市科学版),2003,20(4):20-23.(ZHANG Yao -ting,QIU Ji-sheng.Application of ANSYS in nonlinear analysis of prestressed reinforced concrete structure[J].Journal of Huazhong University of Science and Technology (Urban Science Edition),2003,20(4):20-23.(in Chinese))
[2] Podolny Jr W.Corrosion of prestressing steels and its mitigation[J].PCI Journal,1992,37(5):34-35.
[3] 吴雪峰.锈蚀钢绞线力学性能和粘结性能研究[D].中南大学,2014.(WU Xue -feng.Research on Mechanical Properties and Bonding Performance of Corroded Prestressing Steel Strand[D].Central South University,2014.(in Chinese))
[4] 张新民,柴发合,王淑兰,等.中国酸雨研究现状[J].环境科学研究,2010,23(5):527-532.(ZHANG Xin-min,CHAI Fa-he,WANG Shu-lan,et al.Research progress of acid precipitation in China[J].Research of Environmental Sciences,2010,23(5):527-532.(in Chinese))
[5] 李富民,邓天慈,王江浩,等.预应力混凝土结构耐久性研究综述[J].建筑科学与工程学报,2015,32(2):1-20.(LI Fu-min,DENG Tian-ci,WANG Jiang-hao,et al.Review of research on durability of prestressed concrete structures[J].Journal of Architecture and Civil Engineering,2015,32(2):1-20.(in Chinese))
[6] 杨枫,薛伟辰.高预应力度混凝土梁抗震性能探讨[J].地震工程与工程振动,2006,26(6):108-113.(YANG Feng,XUE Wei-chen.Studies on seismic performance of prestressed concrete beams with high PPR[J].Earthquake Engineering and Engineering Vibration,2006,26(6):108-113.(in Chinese))
[7] 范颖芳,周晶.受腐蚀钢筋混凝土构件受力性能研究现状[J].土木工程学报,2004,37(7):23-28.(FAN Ying-fang,ZHOU Jing.State of the art load bearing property of corroded reinforced concrete members[J].China Civil Engineering Journal,2004,37(7):23-28.(in Chinese))
[8] Rodriguez J,Ortega L M,Casal J.Load carrying capacity of concrete structures with corroded reinforcement[J].Construction and Building Materials,1997,11(4):239-248.
[9] 曾严红,顾祥林,张伟平,等.混凝土中钢筋加速锈蚀方法探讨[J].结构工程师,2009,25(1):101-105.(ZENG Yan-hong,GU Xiang-lin,ZHANG Wei-ping,et al.Accelerated corrosion technique for reinforcement steel bars in concrete[J].Structural Engineers,2009,25(1):101-105.(in Chinese))
[10] Darmawan M S,Stewart M G.Spatial time -dependent reliability analysis of corroding pretensioned prestressed concrete bridge girders [J].Structural Sa-fety,2007,29(1):16-31.
[11] 陈梦成,罗晶,许开成.江西省酸雨特征分析及预测模型[J].环境科学与技术,2014,37(10):167-170.(CHEN Meng-cheng,LUO Jing,XU Kai-cheng.Characteristics and prediction model of Jiangxi acid rain[J].Environmental Science & Technology,2014,37(10):167-170.(in Chinese))
[12] 余芳.钢绞线腐蚀后的部分预应力混凝土梁受力性能研究[D].大连理工大学,2013.(YU Fang.Study on Mechanical Performance of Partial Prestressed Concrete Beams with Corroded Strand[D].Dalian University of Technology,2013.(in Chinese))
[13] 李富民,袁迎曙,王波,等.腐蚀钢绞线预应力混凝土梁受弯承载力评估[J].建筑结构学报,2011,32(2):10-16.(LI Fu-min,YUAN Ying-shu,WANG Bo,et al.Evaluation on flexural strength of prestressed concrete beams with corroded steel strands[J].Journal of Building Structures,2011,32(2):10-16.(in Chinese))
[14] Hognestad E.Study of Combined Bending and Axial Load in Reinforced Concrete Member [R].University of Illinois at Urbana Champaign,1951.
[15] 毛伟,贾金青,余芳.分离模型预应力混凝土梁数值模拟[J].铁道建筑,2011(7):17-19.(MAO Wei,JIA Jin-qing,YU Fang.Numerical simulation of prestressed concrete beams with separation model[J].Railway Engineering,2011(7):17-19.(in Chinese))
[16] 张耀庭,邱继生.ANSYS在预应力钢筋混凝土结构非线性分析中的应用[J].华中科技大学学报(城市科学版),2003,20(4):20-23.(ZHANG Yao -ting,QIU Ji-sheng.Application of ANSYS in nonlinear analysis of prestressed reinforced concrete structure[J].Journal of Huazhong University of Science and Technology (Urban Science Edition),2003,20(4):20-23.(in Chinese))