Citation: | ZHAO Haitao, DING Jian, YANG Guo, XIANG Yu, XU Wen, CHEN Yuzhi. Experimental Investigation of Relative Humidity Response in Early-Age Concrete Under Tensile Stress[J]. Journal of Southwest Jiaotong University, 2024, 59(5): 1104-1112. doi: 10.3969/j.issn.0258-2724.20220134 |
In order to systematically investigate the response law of the internal relative humidity of concrete at an early age to different tensile stress levels, a test method of the internal relative humidity of the concrete under constant axial tension was developed in this paper, and the response law of the relative humidity under different tensile stresses was studied experimentally. According to the experimental results and theoretical analysis, a linear model of the relative humidity and tensile stress of early-age concrete under one-side drying conditions was presented. The results show that the tensile stress causes the instantaneous decrease in the internal relative humidity of the concrete. When the tensile stress increases from 0.8 MPa to 3.2 MPa, the relative humidity change at the depth of 50, 75, and 100 mm of the concrete increases from 0.5%, 0.4%, and 0.3% to 0.8%, 0.7%, and 0.6%, respectively. At the same time, with the increase in tensile stress, the decrease in the relative humidity gradually increases. Under the same tensile stress, the response of relative humidity of the concrete, close to the exposed surface, to tensile stress which is is more obvious. The relative humidity gradually recovers during the tensile stress loading, and the time is about 2.5 h. A similar phenomenon also occurs during the compressive stress loading, and the time is about 20.0 h. Therefore, the relative humidity recovery time is shorter during the tensile stress loading.
[1] |
王晓莹. 早龄期高性能约束砂浆环开裂机制数值模拟[D]. 重庆: 重庆大学, 2015.
|
[2] |
杨荣山,李莹,许钊荣,等. 多雨地区双块式无砟轨道湿态混凝土力学性能[J]. 西南交通大学学报,2022,57(4): 840-847. doi: 10.3969/j.issn.0258-2724.2017.01.008
YANG Rongshan, LI Ying, XU Zhaorong, et al. Mechanical properties of wet concrete inside double-block ballastless tracks in rainy areas[J]. Journal of Southwest Jiaotong University, 2022, 57(4): 840-847. doi: 10.3969/j.issn.0258-2724.2017.01.008
|
[3] |
LIU J P, TIAN Q, WANG Y, et al. Evaluation method and mitigation strategies for shrinkage cracking of modern concrete[J]. Engineering, 2021, 7(3): 348-357. doi: 10.1016/j.eng.2021.01.006
|
[4] |
ZHAO H T, JIANG K D, YANG R, et al. Experimental and theoretical analysis on coupled effect of hydration, temperature and humidity in early-age cement-based materials[J]. International Journal of Heat and Mass Transfer, 2020, 146: 118784.1-118784.9.
|
[5] |
POWERS T C. The thermodynamics of volume change and creep[J]. Matériaux et Construction, 1968, 1(6): 487-507.
|
[6] |
杜明月. 基于微孔结构演化的早龄期混凝土热-湿-力耦合模型研究[D]. 杭州: 浙江大学, 2015.
|
[7] |
ZHAO H T, JIANG K D, HONG B, et al. Experimental and numerical analysis on coupled hygro-thermo-chemo-mechanical effect in early-age concrete[J]. Journal of Materials in Civil Engineering, 2021, 33(5): 04021064.1-04021064.12.
|
[8] |
WYRZYKOWSKI M, LURA P. RH dependence upon applied load: experimental study on water redistribution in the microstructure at loading[C]//Proceedings of the 10th International Conference on Mechanics and Physics of Creep, Shrinkage and Durability of Concrete and Concrete Structures. Vienna: American Society of Civil Engineers, 2015: 339-347.
|
[9] |
国家质量监督检验检疫总局, 中国国家标准化管理委员会. 通用硅酸盐水泥: GB 175—2007[S]. 北京: 中国标准出版社, 2007.
|
[10] |
中华人民共和国住房和城乡建设部. 混凝土物理力学性能试验方法标准: GB/T 50081—2019[S]. 北京: 中国建筑工业, 2019.
|
[11] |
KOMLOS̆ K, POPOVICS S, NÜRNBERGEROVÁ T, et al. Ultrasonic pulse velocity test of concrete properties as specified in various standards[J]. Cement and Concrete Composites, 1996, 18(5): 357-364. doi: 10.1016/0958-9465(96)00026-1
|
[12] |
国家能源局. 水工混凝土试验规程: DL/T 5150—2017[S]. 北京: 中国电力出版社, 2018.
|
[13] |
ZHANG J, HOU D W, SHE W. Experimental study on the relationship between shrinkage and interior humidity of concrete at early age[J]. Magazine of Concrete Research, 2010, 62(3): 191-199. doi: 10.1680/macr.2010.62.3.191
|
[14] |
DERJAGUIN B. A theory of capillary condensation in the pores of sorbents and of other capillary phenomena taking into account the disjoining action of polymolecular liquid films[J]. Progress in Surface Science, 1992, 40: 46-61. doi: 10.1016/0079-6816(92)90032-D
|
[15] |
BROUWERS H J H. The work of powers and brownyard revisited: Part 1[J]. Cement and Concrete Research, 2004, 34: 1697-1716. doi: 10.1016/j.cemconres.2004.05.031
|
[16] |
DELSAUTE B, BOULAY C, STÉPHANIE S. Creep testing of concrete since setting time by means of permanent and repeated minute-long loadings[J]. Cement and Concrete Composites, 2016, 73: 75-88. doi: 10.1016/j.cemconcomp.2016.07.005
|
[17] |
LIU C, LIU H W, XIAO J Z, et al. Effect of old mortar pore structure on relative humidity response of recycled aggregate concrete[J]. Construction and Building Materials, 2020, 247: 118600.1-118600.10.
|
[18] |
WYRZYKOWSKI M, LURA P. The effect of external load on internal relative humidity in concrete[J]. Cement and Concrete Research, 2014, 65: 58-63. doi: 10.1016/j.cemconres.2014.07.011
|
[19] |
MACKENZIE J K. The elastic constants of a solid containing spherical holes[J]. Proceedings of the Physical Society. Section B, 1950, 63(1): 2-11. doi: 10.1088/0370-1301/63/1/302
|
[20] |
BENTZ D P, GARBOCZI E J, QUENARD D A. Modelling drying shrinkage in reconstructed porous materials: application to porous Vycor glass[J]. Modelling and Simulation in Materials Science and Engineering, 1998, 6(3): 211-236. doi: 10.1088/0965-0393/6/3/002
|
[21] |
周航. 自密实自养护混凝土研制及性能试验研究[D]. 重庆: 重庆大学, 2016.
|
[22] |
VLAHINIĆ I, JENNINGS H M, THOMAS J J. A constitutive model for drying of a partially saturated porous material[J]. Mechanics of Materials, 2009, 41(3): 319-328.
|
[23] |
LURA P, JENSEN O M, BREUGEL K V. Autogenous shrinkage in high-performance cement paste: an evaluation of basic mechanisms[J]. Cement and Concrete Research, 2003, 33(2): 223-232.
|
[24] |
NORLING M K. A model on self-desiccation in high-performance concrete[C]//In: self-desiccation and its importance in concrete technology, proceedings of the international research seminar. Sweden: [s.n.], 1997: 141-157.
|
[25] |
PANTAZOPOULOU S J, MILLS R H. Microstructural aspects of the mechanical response of plain concrete[J]. ACI Materials Journal, 1995, 92: 605-616.
|
[26] |
ZHOU C S, CHEN W, WANG W, et al. Indirect assessment of hydraulic diffusivity and permeability for unsaturated cement-based material from sorptivity[J]. Cement and Concrete Research, 2016, 82: 117-129. doi: 10.1016/j.cemconres.2016.01.002
|
[27] |
SHKOLNIK I E. Effect of nonlinear response of concrete on its elastic modulus and strength[J]. Cement and Concrete Composites, 2005, 27(7/8): 747-757.
|
[28] |
张子明,周红军,殷波. 基于等效时间的混凝土徐变[J]. 河海大学学报(自然科学版),2005,33(2): 173-176.
ZHANG Ziming, ZHOU Hongju, YIN Bo. Equivalent time based concrete creep[J]. Journal of Hohai University (Natural Sciences), 2005, 33(2): 173-176.
|
[29] |
周济,陈宗平,唐际宇,等. 一年龄期内超高泵送SCC力学性能时变研究[J]. 西南交通大学学报,2022,57(6): 1175-1183. doi: 10.3969/j.issn.0258-2724.20200746
ZHOU Ji, CHEN Zongping, TANG Jiyu, et al. Time variation of mechanical properties of ultra-high pumped self-compacting concrete within one year of age[J]. Journal of Southwest Jiaotong University, 2022, 57(6): 1175-1183. doi: 10.3969/j.issn.0258-2724.20200746
|
[30] |
GRASLEY Z C, SCHERER G W, LANGE D A, et al. Dynamic pressurization method for measuring permeability and modulus: Ⅱ. cementitious materials[J]. Materials and Structures, 2007, 40(7): 711-721. doi: 10.1617/s11527-006-9184-y
|