| Title |
Influence of Qualities of Crushed Sandon Properties of Concrete using Mixed Fine Aggregate |
| Authors |
Park Cho-Bum ; Lee Mun-Hwan ; Ryu Deug-Hyun |
| Keywords |
Mixed Fine Aggregate ; Density ; Passing Ratio of 0.08mm Sieve ; Solid Volume Ratio for Shape Determination |
| Abstract |
As the shortage of natural & good qualities aggregate for concrete, so the development of alternative aggregate is demanded progressively. In this study, in order to use positively crushed sand for concrete, the experiment was progressed by mixed use of crushed sand and sea sand. The crushed sand was classified 4 kinds according to dosage method of raw ore and density based on the survey of origin place of crushed sand in Seoul metropolitan district. The results of qualities of crushed sand and properties of concrete using mixed fine aggregate are as follows.(1) The qualities of crushed sand were not highly different each other except for the amount of fine particles and solid volume ratio for shape determination, and the whole properties of crushed sand were satisfied with Korean Industrial Standards except for solid volume ratio for shape determination, and the amount of fine particles of sand differed highly. The density was proportioned to the amount of fine particles of crushed sand. (2) The slump and air content of concrete using mixed fine aggregate were lower than basis mix, as the substitute ratio of crushed sand was increased, so it is judged that the workability of concrete have more influence on density of crushed sand than dosage method of raw ore. (3) The compressive strength of concrete showed on the contrary with workability, that is, as slump and air content of concrete decreased, the strength of concrete increased. Accordingly the relation to workability and strength were in inverse proportion to irrespective of kinds and substitute ratio of crushed sand.Therefore, the properties of concrete using mixed fine aggregate were more influenced on density rather than dosage method of raw ore. In conclusion, it is very important not only to use crushed sand having low density, but also to control fine particles and solid volume ratio for shape determination of high density crushed sand. |