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J4  2012, Vol. 46 Issue (10): 1887-1892    DOI: 10.3785/j.issn.1008-973X.2012.10.023
土木工程     
软水侵蚀混凝土的性能劣化细观机理
王海龙, 郭春伶, 孙晓燕, 金伟良
浙江大学 土木工程学系,浙江 杭州 310058
Degradation mesomechanism of concrete deteriorated by soft water
WANG Hai-long, GUO Chun-ling, SUN Xiao-yan, JIN Wei-liang
Department of Civil Engineering, Zhejiang University, Hangzhou 310058, China
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摘要:

依据试验研究结果和细观断裂力学研究混凝土经流动软水侵蚀后劈拉性能变化的细观机理.试验通过自制的流动软水模拟装置对混凝土试块进行长期侵蚀,测试了侵蚀过程中混凝土孔隙和侵蚀前后混凝土劈拉强度的变化规律.试验结果表明:混凝土试块在历经软水侵蚀后,孔隙率和有害孔径率明显增大,劈拉强度随侵蚀时间的增长逐渐降低.根据断裂力学和侵蚀前后混凝土孔隙的变化规律提出用于理论分析的侵蚀混凝土受拉裂纹构型;以裂纹间距与裂纹初始长度的比值为可变参数,分析混凝土受劈拉时断裂强度与裂纹特征参数之间的关系,对混凝土劈拉强度的变化进行预测.模型分析结果表明,基于弹塑性理论的模型预测结果与试验值较一致.

Abstract:

The change mesomechanism of split tensile strength of concrete deteriorated by soft water was analyzed based on meso-fracture mechanics and experimental results. A special device was designed to simulate the leaching of concrete caused by soft water. Some experiments were conducted to test the porosity and the split tensile strengths of concretes. The experimental results indicate that the porosity and the harmful aperture ratio of deteriorated concrete increase significantly and the split tensile strength decreases gradually along with the erosion time. A crack model for theoretical analysis was proposed based on the porosity changes of deteriorated and undeteriorated concretes and the fracture mechanics. The relationships between split tensile strength and crack parameters were discussed using the ratio of initial crack length and crack distance as variances. The split tensile strength of concrete was predicted based on the proposed models. Results showed that the elastic-plastic model accorded well with the experimental results.

出版日期: 2012-10-01
:  TU 528.1  
基金资助:

国家自然科学基金资助项目(51178417, 50809061);中央高校基本科研业务费专项资金资助项目;浙江大学海洋交叉引导基金资助项目.

通讯作者: 孙晓燕,女,副教授.     E-mail: selina@zju.edu.cn
作者简介: 王海龙(1974—),男,副教授,从事混凝土材料耐久性的研究.E-mail: hlwang@zju.edu.cn
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引用本文:

王海龙, 郭春伶, 孙晓燕, 金伟良. 软水侵蚀混凝土的性能劣化细观机理[J]. J4, 2012, 46(10): 1887-1892.

WANG Hai-long, GUO Chun-ling, SUN Xiao-yan, JIN Wei-liang. Degradation mesomechanism of concrete deteriorated by soft water. J4, 2012, 46(10): 1887-1892.

链接本文:

http://www.zjujournals.com/eng/CN/10.3785/j.issn.1008-973X.2012.10.023        http://www.zjujournals.com/eng/CN/Y2012/V46/I10/1887

[1] 汝乃华,姜忠胜.大坝事故与安全拱坝[M]. 北京:中国水利水电出版社,1995: 24-25.
[2] 刑林生,谭秀娟.我国水电站大坝安全状况及修补处理综述[J].大坝与安全,2001,15(5): 4-8.
XIN Linsheng, TAN Xiujuan. Dam safety status and repair of hydropower stations in China [J]. Dam and Safety, 2001, 15(5): 4-8.
[3] 梁坤生,伍智钦.广蓄二期工程尾水洞混凝土表面侵蚀探讨[J].水力发电,2001,13 (11): 37-39.
LIANG Kunsheng, WU Zhiqin. Discussion on the concrete surface erosion of tailrace tunnel of guangzhou pumped storage plant (second stage) [J]. Water Power, 2001, 13(11): 37-39.
[4] MAINGUY M, TOGNAZZI C, TORRENTI J M, et al. Modeling of leaching in pure cement pastes and mortar [J]. Cement and Concrete Research, 2000, 30(1): 83-90.
[5] CARDE C, FRANCOIS R. Modeling the loss of strength and porosity increase due to the leaching of cement pastes [J]. Cement and Concrete Composites, 1999, 21(3): 181-188.
[6] 李金玉,曹建国,林莉.水工混凝土耐久性研究的新进展[J].水力发电,2001,13(4): 44-47.
LI Jinyu, CAO Jianguo, LIN Li. New development of the study on hydraulic concrete durability [J]. Water Power, 2001, 13(4): 44-47.
[7] 邢林生,聂广明.混凝土坝坝体溶蚀病害及治理[J].水力发电,2003, 15(11): 60-63.
XIN Linsheng, NIE Guangming. Corrosion and treatment of concrete dam body [J]. Water Power, 2003, 15 (11): 60-63.
[8] 李庆斌,王海龙.水环境对混凝土力学性能的影响研究述评[J].中国科技论文在线,2006,1(2): 83-94.
LI Qingbin, WANG Hailong. Influence of ambient water on properties of concrete [J]. Science Paper Online, 2006, 1 (2): 83-94.
[9] SL3522006,水工混凝土试验规范[S].北京:中国水利水电出版社,2006: 108-109.

[10] 王海龙,李庆斌.不同加载速度下饱和混凝土的劈拉试验研究及强度变化机理[J].工程力学,2007, 24(2): 105-109.
WANG Hailong, LI Qingbin. Experiments on saturated concrete under different splitting tensile rate and mechanism on strength change [J]. Engineering Mechanics, 2007, 24(2): 105-109.
[11] ZHENG D, LI Q B. An explanation for rate effect of concrete strength based on fracture toughness including free water viscosity [J]. Engineering Fracture Mechanics, 2004, 71(16/17): 2319-2327.
[12] DUGDALE D S. Yielding of steel containing slit [J]. Journal of the Mechanics and Physics of Solids, 1960, 8(2): 100-104.
[13] 王海龙,李庆斌.饱和混凝土静动力抗压强度变化的细观力学机理[J].水利学报,2006, 37(8): 958-962.
WANG Hailong, LI Qingbin. Micromechanism of static and dynamic strengths for saturated concrete [J]. Journal of Hydraulic Engineering, 2006,37(8): 958-962.
[14] 冯西桥,余寿文.准脆性材料细观损伤力学[M].北京:高等教育出版社,2002: 28-39.
[15] HATZORT Y H, PALCHIK V. The Influence of grain size and porosity on crack initiation stress and critical flaw length in dolomites [J]. International Journal of Rock Mechanics and Mining Science, 1997, 34(5): 805-816.
[16] FENG X Q, YU S W. Analyses of damage localization at crack tip in a brittle damaged material [J]. Engineering Fracture Mechanics, 1996,53(2): 77-169.
[17] TADA H, PARIS P C, IRWIN G R. The stress analysis of cracks handbook [M]. 3rd ed. St. Louis: Paris Production Incorporated, 2000: 165-170.

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