| Title |
Analysis of the Influencing Factors on Estimation of Compressive Strength of Core Specimen |
| Authors |
Baik Byung-Hoon ; Song Sung-Jin |
| Keywords |
Small Size Core ; Kinds of Cement ; Kinds of Aggregate ; Maximum Size of Coarse Aggregate ; Experimental Factors |
| Abstract |
This study is intended to investigate the influencing factors on the compressive strength of core specimens such as mixture factors(W/C), material factors(kinds of cement, replacing ratio of admixture, kinds of aggregate and maximum size of coarse aggregate) and experimental factors. According to the result, as for the effect of W/C, the compressive strength of core specimen drops higher in W/C 45% than in W/C 55% in comparison with that of standard specimen, and as for kinds of cement, it does lower in the case of UHC and AMC than in the case of OPC, but the effect of admixture is very minute. The compressive strength of core specimen of concrete using basalt aggregate shows the similar tendency to that of granite aggregate, but decreases a bit in the case of limestone. The reducing ratio of the compressive strength of 25mm core specimen is least when the maximum size of aggregate is 10mm. But the compressive strength of 50 and 100mm core specimen is almost not influenced by the maximum size of aggregate. As for the influence of drilling direction, when core specimens are obtained from the place parallel to placing direction, compressive strength of core specimens is higher than those perpendicular to placing direction. And considering drilling position, compressive strength of core specimen is higher at the edge of cubic specimen than at the center, and at the bottom of cubic specimen than that at the top. As h/d ratio increases and rotation speed of drilling machine goes up, compressive strength decreases, regardless of core diameter. |