Brine-freeze-thaw Durability and Crack Density Model of Concrete in Salt Lake Region
Wei Gong , Hongfa Yu , Haiyan Ma , Wenliang Han
Journal of Wuhan University of Technology Materials Science Edition ›› 2020, Vol. 35 ›› Issue (3) : 561 -570.
The brine-freeze-thaw durability (defined as the durability under freeze-thaw cycles in Qinghai salt lake brine) of concrete (ordinary Portland cement concrete (OPC), high performance concrete (HPC-a), high performance concrete with steel fiber (HPC-b), and high performance concrete with high Young’s modulus polyethylene fiber (HPC-c)) was systematically investigated by the relative dynamic elastic modulus, the relative mass, the appearance, the scanning electron microscopy, and the X-ray diffraction. In addition, the low-temperature physical and chemical corrosion mechanism and a crack density model after the modified relative dynamic elastic modulus being taken into consideration were proposed. The results show that the deterioration of OPC is the severest, followed by HPC-a, HPC-c and HPC-b. The admixture or the fiber is mixed into concrete, which can improve the brine-freeze-thaw durability of concrete. The critical mass growth of the failure of concrete is 3.7%. The cause of the deterioration of concrete under the brine-freeze-thaw cycles is physical and chemical corrosion, not freezing and thawing. The crack density model can effectively describe the deterioration evolution of concrete.
brine-freeze-thaw durability / relative dynamic elastic modulus / relative mass / microanalysis / modeling
| [1] |
|
| [2] |
|
| [3] |
Mehta PK. Concrete Durability-Fifty Years Progress[R]. Progress of 2nd International Conference on Concrete Durability, Montreal, 1991 |
| [4] |
|
| [5] |
|
| [6] |
|
| [7] |
|
| [8] |
|
| [9] |
|
| [10] |
|
| [11] |
|
| [12] |
|
| [13] |
|
| [14] |
|
| [15] |
|
| [16] |
|
| [17] |
|
| [18] |
|
| [19] |
|
| [20] |
|
| [21] |
|
| [22] |
|
| [23] |
|
| [24] |
|
| [25] |
|
| [26] |
|
| [27] |
ASTM. Standard Test Method for Slump of Hydraulic-cement Concrete[S]. ASTM C143/C143M-2012, 2012 |
| [28] |
ASTM. Standard Test Method for Air Content of Freshly Mixed Concrete by the Volumetric Method[S].ASTM C173/C173M-2014, 2014 |
| [29] |
ASTM. Standard Practice for Making and Curing Concrete Test Specimens in the Laboratory[S]. ASTM C192/C192M-2014, 2014 |
| [30] |
ASTM. Standard Test Method for Resistance of Concrete to Rapid Freezing and Thawing[S]. ASTM C666/C666M-2015, 2015 |
| [31] |
|
| [32] |
|
| [33] |
SBTS. Standard for Test Methods of Long-term Performance and Durability of Ordinary Concrete[S]. GB/T50082-2009, 2009 |
| [34] |
|
| [35] |
|
| [36] |
|
| [37] |
|
| [38] |
|
| [39] |
|
| [40] |
|
| [41] |
|
| [42] |
|
| [43] |
|
| [44] |
|
| [45] |
|
| [46] |
|
| [47] |
Mu R, Sun W, Miao CW, et al. Degradation of Concrete Subjected to Simultaneous Attack of Freeze-thaw and Sustained Flexural Load[C]. 1st International Conference on Microstructure Related Durability of Cementitious Composites, Nanjing, 2008 |
| [48] |
BSI. Structural Use of Concrete-part 2: Code of Practice for Special Circumstances[S]. BS 8110-2-1985, 1985 |
| [49] |
|
| [50] |
|
| [51] |
|
/
| 〈 |
|
〉 |