Issue 68

K. W. Nindhita et alii, Frattura ed Integrità Strutturale, 68 (2024) 140-158; DOI: 10.3221/IGF-ESIS.68.09

Before the mix design process and the manufacture of the specimens are carried out, several tests are carried out: a specific gravity test, water absorption test, gradation test, abrasion test, and sludge content test. From the results of the sand test, it was found that the fine modulus value was 2.403, and the gradation criteria met the requirements, as shown in Figure 3 and Table 1. Meanwhile, the gravel test results are shown in Table 2.

Figure 3: Fine grain gradation chart.

Test Type

Value 2.403 2.606 2.635 2.684 1.112

Unit

Standard

Fine modulus

- - - -

SNI ASTM C136:2012 [26]

Bulk specific gravity

SNI 1970:2008 [30] SNI 1970:2008 [30] SNI 1970:2008 [30] SNI 1970:2008 [30]

Saturated surface dry specific gravity

Apparent specific gravity

Water absorption

% %

Mud content

1.60

SNI ASTM C117:2012 [31]

Table 1: Fine aggregate test data.

Test Type

Value 2.6614 2.6933 2.7493

Unit

Standard

Bulk specific gravity

- - -

SNI 1969:2008 [27] SNI 1969:2008 [27] SNI 1969:2008 [27] SNI 1969:2008 [27]

Saturated surface dry specific gravity

Apparent specific gravity

Water absorption

1.2 1.5

% % %

Mud content

SNI ASTM C117:2012 [31]

Abrasion

21

SNI 2417:2008 [32]

Table 2: Coarse aggregate test data.

M ETHODS

he planning of the concrete mixture uses ACI 211.1-91 concerning Standard Practice for Selecting Proportions for Normal, Heavyweight, and Mass Concrete [33] with a design concrete quality of 30 MPa and w/c ratio of 0.43. The number of proportions of Bacillus subtilis bacteria added to the concrete mixture, namely, 0%, 0.1%, 0.6%, and 1.5% by weight of sand. The proportions of the mix design concrete per 1 m 3 are shown in Table 3. T

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