采用自然浸泡和干湿循环的试验方法, 研究了碳化后的粉煤灰混凝土（FAC）、 大掺量矿物掺合料混凝土（HVMAC）及高性能混杂纤维增强膨胀混凝土（HPHFREC）在5%硫酸镁溶液中的损伤过程。结果表明： 碳化一定程度上密实了混凝土表层, 但改变了混凝土表层的化学组成, 降低混凝土的抗硫酸镁腐蚀性能。干湿循环加速硫酸镁的扩散作用, 扩展混凝土内部原有的微裂缝。在碳化＋硫酸镁双重破坏因素作用下, HVMAC具有优异的抗腐蚀性能, 适合应用于硫酸镁腐蚀的严酷环境; 在碳化＋干湿循环＋硫酸镁多重破坏因素作用下, HPHFREC2的三元纤维混杂起到明显的增强增韧效果, 抗腐蚀性能较好。
Deterioration of carbonized fly ash concrete (FAC), concrete with high volume mineral admixture (HVMAC), and high performance hybrid fibers reinforced expansive concrete (HPHFREC) exposed to 5% magnesium sulfate solution was investigated. Two corrosion regimes were employed: natural immersion and dry-wet cycle. Experiment results show that carbonation changes the chemical component of concrete surface and reduces the resistance of concrete to magnesium sulfate attack, though carbonation compacts the concrete surface to some extent. The dry-wet cycles accelerate the diffusion of magnesium sulfate and develop the micro-crack of concrete. Under combined action of carbonation and magnesium sulfate, HVMAC gets the best resistance to sulfate attack and is applicable to the atrocious environment, but FAC which has been broken up is not applicable to the concrete engineering in such environment. Under combined action of carbonation, dry-wet cycle, and magnesium sulfate, HPHFREC2, of which the reinforced effect of the fibers is obviously well, shows the better resistance of concrete to sulfate attack.
参考文献
| [1] | AI-Dulaijan SU, Maslehuddin M, AI-Zahrani M M, et al.Sulfate resistance of plain and blended cements exposed to varying concentrations of sodium sulfate [J].Cement Concrete Composites, 2003, 25(4/5): 429-437. |
| [2] | Sideris K K, Savva A E, Papayianni J. Sulfate resistance and carbonation of plain and blended cements[J].Cement Concrete Composites, 2006, 28 ( 1 ) : 47- 56. |
| [3] | Hekala E E, Kisharb E, Mostafab H. Magnesium sulfate attack on hardened blended cement pastesunder different circumstances [J]. Cement and Concrete Research. 2002, 32(9) : 1421-1427. |
| [4] | Tikalsky P J, Carrasquillo R L. Influence of fly ash on the sulfate resistance of concrete [J].ACI Materials Journal, 1992, 89(1): 69-75. |
| [5] | 余红发,孙伟,鄢良慧,等.盐湖地区干燥气候和碳化作用对混凝土强度和耐久性的影响[J].混凝土,2003(10):28一R1. |
| [6] | 王琴,杨鼎宜.干湿循环对混凝土硫酸盐侵蚀的影响[J].混凝土,2008(3):22-24. |
| [7] | 周永祥,阎培渝.固化盐渍土经干湿循环后力学性能变化机理[J].建筑材料学报,2006,9(6):735-741. |
| [8] | 张伟勤,刘连新.代大虎.混凝土在卤水、淡水中的干湿循环腐蚀试验研究[J].青海大学学报(自然科学版).2006,24(4):25-29. |
| [9] | Yang Liming, Yu Hongfa, Ma Haiyan. Deterioration of high performance hybrid fibers reinforced expansive concrete exposed to magnesium sulfate solution [ C]. International Conference on Transportation Engineering, 2009, 2614-2619. |
| [10] | 罗骐先,BungeyJH.用纵波超声换能器测量砼表面波速和动弹性模量[J].水利水运科学研究,1996(3):264-27. |
| [11] | 张誉,蒋利学,张伟平,等.混凝土结构耐久性概论[M].上海:上海科学技术出版社,2003:34-36. |
| [12] | 柳俊哲.混凝土碳化研究与进展(3)--腐蚀因子的迁移[J].混凝土,2006(1):51-54. |
| [13] | 罗立峰,周建春,黄培彦.聚合物钢纤维混凝土的增强机理分析[J].复合材料学报,2002,19(3):46-50. |
| [14] | 徐松林,唐志平,胡元育,等.纤维增强水泥基复合材料压剪破坏的细观试验研究[J].复合材料学报,2005,22(1):92-101. |
| [15] | 刘赞群.混凝土硫酸盐侵蚀基本机理研究[D].长沙:中南大学,2010. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%