Hệ số thực nghiệm chuyển đổi cường độ chịu nén của bê tông cường độ cao xác định trên mẫu đúc và mẫu khoan

High-strength concrete has been used increasingly in construction in our country. Currently, the compressive strength of high-strength concrete on molded and drilled samples should be calculated with a conversion factor specified in national standards. However, these factors are significantly different from practice. The study presented in this paper has shown that the ratio of compressive strength determined on the cube sample (a150) compared to the cylinder sample (D150H300) is 1.13, the cube sample compared to the drilled sample (D57H57) is 0.98, and the cylinder sample compared to the drilled sample is 0.87. The difference in compressive strength when converted according to the standard and according to the experimental factor when using small diameter drilled samples in the experiment is 18 % for cube samples and 26 % for cylinder samples. Therefore, we propose a larger-scale study to supplement the data to review the current national standards.