EVALUASI MUTU DAN PRODUKTIVITAS PADA PENGECORAN PLAT LANTAI GROUND LEVEL MENGGUNAKAN LINE CONCRETE PUMP (STUDI KASUS: PROYEK PEMBANGUNAN GEDUNG D ZONA 3 GROUND LEVEL D-E/5 SAMPAI GROUND LEVEL F-E/11)

In construction projects, quality control of the compressive strength of concrete is usually only carried out by quality control with a slump test at the arrival of the mixer truck. There are several projects that use a line concrete pump to distribute concrete using a pipe that is too long and the quality of the concrete is feared to decline. Therefore, testing the effect of line concrete pump on the compressive strength value of concrete by testing in the field using a sample of 20 concrete specimens taken from the end of the pipe (output) 5 mixer trucks. Tests in the form of slump value test, concrete compressive strength test and analysis of heavy equipment productivity and duration. Compressive strength analysis is in the form of acceptance of compressive strength based on SNI 03-2847-2019, the difference in the decrease in compressive strength and SQC. To determine the relationship between the decrease in compressive strength with 3 main variables, namely the difference in slump value, sampling time and number of pipes, simple and multiple linear regression analysis were used. The results of this test are that the compressive strength value is included in the controlled category, the quality of the concrete is in accordance with the SNI 03-2847-2019 criteria, for the slump value at the input is 100% but at the output it only enters 20%. The compressive strength of concrete at the age of 7 days of output test object has a decrease percentage of 100% and has an average reduction of 11.41% lower than the input, whereas the output test object aged 28 days has a decrease percentage of 90% and has an average reduction of 11.41%. the average decrease was 9.47% lower than the input. For the results of the regression of 3 variables, the difference in slump value and the difference in sampling time has a significant effect, while the number of pipes has no significant effect on the decrease in the compressive strength of the concrete. The productivity of the truck mixer is 0.351 m³ / minute while the concrete pump is 0.334 m³ / minute, for the duration of the truck mixer it takes 7 hours 6 minutes and on the concrete pump for 7 hours 28 minutes.