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Sieve Analysis Graph

2.36 4.75
101
Percentage Passing (%) 61
81

41
0.212 0.425 1.18
21
0.015 0.06

1
0.001 0.01 0.1 1 10 100
Sieve size (mm)

Figure 4 Sieve Analysis Graph to a crushed cockle shell as sand replacement

3.2 Mix Proportion

As a guideline for data analysis, control samples were developed. The OPC control mix was designed to
produce concrete with target strength of 30N/mm at 28 days using 1:2:4 mixture ratio as per Table 5. Control
2
sample was produced by using 100% of river sand in the concrete mixture. While for testing samples, 5 mixture
proportions of Cockle Shell Samples (CS) were made to observe the performance of cockle shell particle.
Cockle shell gradually replaced river sand by weight from the range of 4% to 12%. Meanwhile CS 0% was
considered has no cockle shell content because it was created as a control concrete in this study. Table 6 shows
the designed cockle shell mixture proportions. Throughout the experiments, water to cementitious material ratio
(w/b) used was 0.55.

Table 5 Concrete Mixture Ratio (Jabatan Kerja Raya, 2014)

Mixture Ratio Usage

1:5:10 Sites walls in the trenches for hard underground work

1:3:6 Concrete slab, walls and etc

1:2:4 Reinforcement concrete for column and beam

1:1.5:3 Pre-stress concrete, tank and etc

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