PSI - Issue 70

R. Ashwathi et al. / Procedia Structural Integrity 70 (2025) 183–190

185

2.1 Cement:

53 grade Ordinary Portland Cement is incorporated for all concrete sample mixtures (Nevsky Konstantin; Danke, Ilia; Kudyakov, Aleksandr; Kudyakov, Vitaly, 2016). The cement used is fresh and free from lump. The physical properties obtaining to IS 12269-1987 is displayed in the Table.1

Table 1. Properties of Cement S. No. Properties

Results

1. 2. 3. 4. 5. 6.

Standard Consistency

31%

Initial Setting Time (Mins) Final Setting Time (Mins)

32

370

Fineness

3.4%

Specific Gravity

3.2 2.4

Soundness

2.2 Aggregates:

Naturally available aggregates of 20mm is adopted for the investigation. The aggregates used pertain to IS 383 1970 which are free from debris and chemicals (Zhang Zhangyu; Yu, Hongfa; Ma, Haiyan; Da, Bo, 2022). M-Sand is used for investigational in the place of natural river sand that is nearby available. Their properties are given in Table 2. The aggregates passing through 4.75mm sieve is adopted (Mohanraj et al., 2022).

Table 2. Properties of Fine Aggregates S. No Properties

Fine Aggregate

Coarse Aggregate

1. 2. 3. 4.

Specific Gravity Water absorption Fineness modulus Bulk density (kg/ m 3 )

2.56 1.8% 2.46 1570

2.68 1.5% 7.68 1760

2.3 Fibres:

Polyester fibres are made of synthetic materials and are light in weight which enhances dimensional stability and controls plastic shrinkage cracks (K.M et al., 2025). Steel fibres adopted are readily available in varying sizes, shapes and aspect ratio aids in improving the tensile strength, flexural strength and toughness (Li Haitang; Zhen, Xuanjiao; Wen, Chengcheng; Chen, Gang, 2021). These crimped fibres when incorporated into matrix, it influences bonding and controls the crack propagation through spanning the micro cracks and distributing stresses across it effectively (K.M et al., 2025). The hybrid incorporation enhances the structural integrity. The fibres adopted for the investigation are purchased readymade and its features are given in Table 3.

Table 3. Properties of Steel Fibres S.No. Specifications

Polyester Fibre

Steel Fibre

1 2 3 4 5 6 7

Specific Gravity Length used (mm)

1.12

7.40

40

30

Diameter of fibre (mm)

0.5

0.5

Aspect Ratio (l/d)

80

60

Tensile strength (MPa) Unit weight (kg/ m 3 )

960

1200 7640 Good

7640 Good

Resistance to acids and alkalis