| Title |
Influences of Mixing Factors on Drying Shrinkage of the Concrete |
| Authors |
Han Cheon-Goo ; Han Min-Cheol |
| Keywords |
Drying shrinkage ; Water content ; Water to cement ratio(W/C) ; Sand to aggregate ratio(S/a) ; Multi regression model |
| Abstract |
In this paper, tests are carried out in order to investigate properties of drying shrinkage of concrete considering mixing factors such as water to cement ratio(W/C), water content and sand to aggregate ratio(S/a). Three levels of W/C, water content and S/a are selected for experimental parameter. According to experimental results, it is found that drying shrinkage shows high with increase of water content and W/C. This is due to an increase in removal of free water. And, also, increasing S/a in mixture proportion of concrete causes high drying shrinkage. This is because of a decrease in the coarse aggregate content, which plays a major role in restraining from drying shrinkage of concrete, in mixture proportion. When water content is 185kg/m3 in concrete mixture, the values of drying shrinkage at 6 months are shown nearly 5.4～7.6×10-4, which is nearly the same as that of JASS provision(less than 8.0×10-4). The multi regression model considering W/C, water content and S/a on drying shrinkage is obtained as followings ; Y=-0.00112+4.654×10-6W+3.356×10-6S/a+0.0015W/C (R2=0.924) |