西安建筑科技大学学报(自然科学版)

为分析冻融环境下海工混凝土性能的退化规律,对三种配合比的海工混凝土进行了快速冻融试验,并对其物理力学性能及氯离子渗透性能进行分析与评估.试验结果表明:当冻融循环分别超过25次和50次后,海工混凝土的内部损伤和表面损伤先后出现明显的加剧; 总掺量不变但矿粉含量较多时,海工混凝土的抗冻性较优,且掺入适量纳米SiO₂能进一步有效提高混凝土的抗冻性; 以动弹性模量损伤度为依据,对冻融循环作用下海工混凝土的抗压强度损失率及氯离子迁移系数增长率进行分析; 并对动弹性模量损伤度与冻融循环次数的直接关系进行了探讨.分析结果表明经历冻融作用的海工混凝土,其动弹性模量损伤度与抗压强度损失率、氯离子迁移系数增长率之间存在较好的线性关系,且幂函数能有效地反映动弹性模量损伤度与冻融循环次数之间的关系.

In order to analyze the degradation law of marine concrete properties under freeze-thaw environment, the rapid freeze-thaw test was carried out on three kinds of marine concrete mixtures, and the physical and mechanical properties and chloride penetration properties were analyzed and evaluated. The results show that when the freeze-thaw cycles exceed 25 times and 50 times, the internal damage and surface damage of marine concrete are significantly aggravated successively. The frost resistance of marine concrete is better when the total dosage is constant but the content of mineral powder is more, and the frost resistance of concrete can be further improved by adding appropriate amount of nano-SiO₂. Based on the damage degree of dynamic elastic modulus, the loss rate of compressive strength and the growth rate of chloride migration coefficient of marine concrete under freeze-thaw cycle were analyzed. The direct relationship between the damage degree of dynamic elastic modulus and the number of freeze-thaw cycles was also discussed. The analysis results show that there is a good linear relationship between the damage degree of dynamic elastic modulus and the loss rate of compressive strength and the growth rate of chloride migration coefficient for marine concrete subjected to freeze-thaw, and the power function can effectively reflect the relationship between the damage degree of dynamic elastic modulus and the number of freeze-thaw cycles.

引言
1 试验材料与方法
2 试验结果与分析
3 基于动弹性模量损伤度分析受冻混凝土性能退化
4 结论

表1 海工混凝土配合比及力学性能参数<br/>Tab.1 Mix proportion and mechanical properties indexes of marine concrete

表1 海工混凝土配合比及力学性能参数
Tab.1 Mix proportion and mechanical properties indexes of marine concrete

表2 粉煤灰及矿粉的化学组成<br/>Tab.2 Chemical composition of fly ash and mineral powder

表2 粉煤灰及矿粉的化学组成
Tab.2 Chemical composition of fly ash and mineral powder

图1 三种海工混凝土试件<br/>Fig.1 Physical objects of three types of marine concrete specimens

图1 三种海工混凝土试件
Fig.1 Physical objects of three types of marine concrete specimens

图2 横向基频测定<br/>Fig.2 Measurement of transverse fundamental frequency

图2 横向基频测定
Fig.2 Measurement of transverse fundamental frequency

图3 RCM试验
Fig.3 RCM test

图4 冻融循环后冻损试件的质量分析<br/>Fig.4 Mass analysis of test specimens after freeze-thaw cycles

图4 冻融循环后冻损试件的质量分析
Fig.4 Mass analysis of test specimens after freeze-thaw cycles

图5 冻融循环后冻损试件的动弹性模量分析<br/>Fig.5 Dynamic elastic modulus analysis of test specimens after freeze-thaw cycles

图5 冻融循环后冻损试件的动弹性模量分析
Fig.5 Dynamic elastic modulus analysis of test specimens after freeze-thaw cycles

图6 冻融循环作用后试块的抗压强度分析<br/>Fig.6 Compressive strength analysis of test blocks after freeze-thaw cycles

图6 冻融循环作用后试块的抗压强度分析
Fig.6 Compressive strength analysis of test blocks after freeze-thaw cycles

图7 冻融循环作用后试块的氯离子迁移系数分析<br/>Fig.7 Chloride migration coefficient analysis of test specimens after freeze-thaw cycles

图7 冻融循环作用后试块的氯离子迁移系数分析
Fig.7 Chloride migration coefficient analysis of test specimens after freeze-thaw cycles

图8 DE与n之间关系模型<br/>Fig.8 Relation model of between DE and n

图8 DE与n之间关系模型
Fig.8 Relation model of between DE and n

图9 DE与n之间幂函数模型<br/>Fig.9 Power function model between DE and n

图9 DE与n之间幂函数模型
Fig.9 Power function model between DE and n

图10 Δfc与DE之间的关系<br/>Fig.10 Relation between Δfc and DE

图10 Δfc与DE之间的关系
Fig.10 Relation between Δfc and DE

图11 ΔDRCM与DE之间的关系<br/>Fig.11 Relation between ΔDRCM and DE

图11 ΔDRCM与DE之间的关系
Fig.11 Relation between ΔDRCM and DE

[1]武海荣, 金伟良, 延永东, 等. 混凝土冻融环境区划与抗冻性寿命预测[J]. 浙江大学学报(工学版), 2012, 46(4):650-657.
[2]关虓, 牛荻涛, 肖前慧. 考虑残余强度修正的混凝土冻融损伤层及轴心受压模型研究[J]. 铁道学报, 2021, 43(3):175-182.
[3]LI G F, SHEN X D. A study of the durability of aeolian sand powder concrete under the coupling effects of freeze-thaw and dry-wet conditions[J]. JOM, 2019, 71(6):1962-1974.
[4]GE Y, YANG W C, Yuan J, et al. Deterioration of concrete freezing-thawing in different salts solution[J]. Key Engineering Materials, 2009, 802:315-321.
[5]ZHANG X, WANG L, ZHANG J. Mechanical behavior and chloride penetration of high strength concrete under freeze-thaw attack[J]. Cold Regions Science and Technology, 2017, 142:17-24.
[6]SAKTHIVEL T, GETTU R, PILLAI R G. Compressive strength and elastic modulus of concretes with fly ash and slag[J]. Journal of the Institution of Engineers(India): Series A, 2019, 100:575-584.
[7]FERREIRA M, KUOSA H, LEIVO M, et al. Concrete performance subject to coupled deterioration in cold environments[J]. Nuclear Engineering & Design, 2016, 323: 228-234.
[8]HU Z, HU B, GUO M, et al. Improving recycled aggregate concrete by compression casting and nano-silica[J]. Nanotechnology Reviews, 2022, 11(1):1273-1290.
[9]COLLEPARDI M. Concrete durability in a marine environment[J]. IOP Conference Series: Materials Science and Engineering, 2021, 1175(1):012018.
[10]中华人民共和国住房和城乡建设部.普通混凝土长期性能和耐久性能试验方法标准:GB/T 50082-2009[S]. 北京:中国建筑工业出版社,2019:8-9.
[11]WANG Y, LIU Z, FU K, et al. Experimental studies on the chloride ion permeability of concrete considering the effect of freeze-thaw damage[J]. Construction and Building Materials, 2020, 236: 117556.
[12]ALSAIF A, BERNAL S A, GUADAGNINI M, et al. Freeze-thaw resistance of steel fibre reinforced rubberised concrete[J]. Construction and Building Materials, 2018, 195:450-458.
[13]ZAHEDI M, RAMEZANIANPOUR A A, RAMEZANIANPOUR A M. Evaluation of the mechanical properties and durability of cement mortars containing nanosilica and rice husk ash under chloride ion penetration[J]. Construction and Building Materials, 2015, 78:354-361.
[14]HONG X, WANG H, SHI F. Influence of NaCl freeze thaw cycles and cyclic loading on the mechanical performance and permeability of sulphoaluminate cement reactive powder concrete[J]. Coatings, 2020, 10(12): 1227.
[15]SONG W L, Li X F, MA K F. The effect of freeze-thaw cycles on mechanical properties of concrete[J]. Advanced Materials Research, 2011, 163: 3429-3432.
[16]ZHANG S, ZHAO B. Research on the performance of concrete materials under the condition of freeze-thaw cycles[J]. European Journal of Environmental and Civil Engineering, 2013, 17(9): 860-871.
[17]SHANG H S, YI T H, SONG Y P. Behavior of plain concrete of a high water-cement ratio after freeze-thaw cycles[J]. Materials, 2012, 5(9): 1698-170.
[18]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:中国建筑工业出版社,2019:12-16.
[19]王月, 安明喆, 余自若, 等. 氯盐侵蚀与冻融循环耦合作用下C50高性能混凝土的耐久性研究[J]. 中国铁道科学, 2014, 35(3):41-46.
[20]LIU M, WANG Y. Damage constitutive model of fly ash concrete under freeze-thaw cycles[J]. Journal of Materials in Civil Engineering, 2012, 24(9): 1165-1174.
[21]曹大富, 葛文杰, 郭容邑,等. 冻融循环作用后钢筋混凝土梁受弯性能试验研究[J]. 建筑结构学报, 2014, 35(6):137-144.
[22]关虓. 冻融环境钢筋混凝土受弯构件的损伤分析与承载力研究[D]. 西安:西安建筑科技大学, 2015.
[23]王佳雯. 混凝土抗压强度与动弹性模量关系试验研究[D]. 武汉: 湖北工业大学, 2017.
[24]ZHANG P, CONG Y, VOGEL M, et al. Steel reinforcement corrosion in concrete under combined actions: The role of freeze-thaw cycles, chloride ingress, and surface impregnation[J]. Construction & Building Materials, 2017, 148:113-121.
[25]ZHANG P, WITTMANN F H, VOGEL M, et al. Influence of freeze-thaw cycles on capillary absorption and chloride penetration into concrete[J]. Cement and Concrete Research, 2017, 100:60-67.
[26]LI B, MAO J, NAWA T, et al. Mesoscopic chloride ion diffusion model of marine concrete subjected to freeze-thaw cycles[J]. Construction and Building Materials, 2016, 125:337-351.
[27]MUTTAQIN H, KOUHEI N, YASUHIKO S, et al. Stress-strain behavior in tension and compression of concrete damaged by freezing and thawing cycles[C]//International RILEM Workshop on Frost Resistance of Concrete. Essen, Germany: RILEM Workshop 2002: 335-342.
[28]CHUNG C W, SHON C S, KIM Y S. Chloride ion diffusivity of fly ash and silica fume concretes exposed to freeze-thaw cycles[J]. Construction & Building Materials, 2010, 24(9):1739-1745.
[29]KESSLER S, THIEL C, GROSSE CU, et al. Effect of freeze-thaw damage on chloride ingress into concrete[J]. Materials and structures, 2017, 50(2):121.1-121.13.

备注

引言

1 试验材料与方法

2 试验结果与分析

3 基于动弹性模量损伤度分析受冻混凝土性能退化

4 结论

期刊信息