PERBANDINGAN KUAT TEKAN BETON MENGGUNAKAN AGREGAT JENUH KERING MUKA DENGAN AGREGAT KERING UDARA

Sari

ABSTRACT

Mixing of concrete in the project site (site mix) must be conducted if there is not concrete plant or away from the project site. In the water need calculation of  mix, the aggregate is considered in a state of saturated surface dry. Aggregate condition that is often found at the project site is dry air state. Based on these issues, it needs to do research on the comparison of compressive strength of concrete using aggregate in saturated surface dry condition to air dry condition. The samples used in this research were concretes cylinder 150 mm x 300 mm. Fine aggregate used was sand and coarse aggregate used was crushed stone/split and gravel. Mix proportions used were 1: 2: 3 and 1: 1.5: 2.5, with  water cement ratio 0.5 and 0.6. There were three specimens of each variation and the total of specimens were 48. Concrete compressive strength testing was carried out at 28 days concrete age. From the results of this research, it can be concluded that the slump value of concrete mixtures using aggregate SSD is larger than using air-dry aggregates. Compressive strength of concrete using air-dry aggregate is greater than using SSD aggregate. Compressive strength of concrete proportion of 1: 2: 3 is less than 1: 1.5: 2.5 on the water cement ratio of 0.5. Compressive strength of concrete in the proportion of 1: 2: 3 is greater than 1: 1.5: 2.5 on aggregate SSD condition, and lower than 1: 1.5: 2.5 on dry air aggregate with the water cement ratio 0.6. Compressive strength of concrete with water cement ratio 0.5 is greater than 0.6.

Keywords: water content of aggregate, proportion by weight, compressive strength.