PSI - Issue 70

J. Arun Prasad et al. / Procedia Structural Integrity 70 (2025) 690–697

693

5. Results & Discussion 5.1. Compressive Strength Cubes of size 150 mm X 150 mm X 150 mm were cast using M 20 grade of concrete and tested after 7days and 28 days for compressive strength for the following combinations.

Table 5.2 Compressive Strength Comparisons

Sample

Compressive Strength

7 days

14 days

28 days

Conventional Concrete

11.61

17.02

21.73

10% Replacement Cenosphere

12.39

17.75

22.41

The compressive strength of M20 concrete with and without 10% Cenosphere replacement at 7, 14, and 28 days. Results shows that the concrete containing 10% Cenospheres consistently outperformed conventional concrete, exhibiting strength improvements of approximately 3 – 7% across all curing periods. This enhancement is attributed to the micro-filling effect and pozzolanic activity of Cenospheres, which contribute to a denser and more durable concrete matrix. The findings suggest that partial replacement of cement with Cenospheres is a promising approach for developing sustainable, lightweight concrete with improved mechanical properties.

Fig. 1. Compressive Strength of Concrete Samples This chart compares the compressive strength of conventional concrete with that of concrete containing 10% Cenosphere replacement over 7, 14, and 28 days. 5.2. Split Tensile Strength This test is carried out by placing the standard cylinder specimen of diameter 150mm and height 300mm horizontally between the loading surface of the compression testing machine and the loading was applied until the failure of the cylinder. Table 2 shows the test result for split tensile strength concrete for M20 concrete.

Table 5.3 Split Tensile Strength Comparison

Sample

Split Tensile Strength 7 days

14 days

28 days

Conventional Concrete

1.74

2.53

3.36

10% replacement Cenosphere

1.96

2.78

3.62