PSI - Issue 70

Muhibur Rahman S. et al. / Procedia Structural Integrity 70 (2025) 627–634

631

sand, as well as the characteristics of CCA and BACA, were detailed in Table 4. The mechanical strength of concrete incorporating CCA and BACA was evaluated using cube, cylinder and prism specimens, as per IS Code 516 (1959). The properties of the concrete mixes incorporating BACA were evaluated at curing of 7, 14, 21, and 28 days. These results were then compared to those of the concrete mixes made with CCA. 4. Result and Discussion 4.1 Compressive Strength (fc) of CC with CCA and BACA The physical and mechanical properties of the aggregate had an influence on the compressive strength results. Having lower water absorption and better particle quality than CCA, it improved the bond with the binder. This resulted in slightly greater strength in BACA composites at all age curing periods. This led to slightly higher strength in BACA mixes at all curing ages. The f c of the concrete mixes, incorporating both CCA and BACA, was assessed at different curing stages, with the results presented in Table 5 and Fig.2. For the M 20 grade concrete, the f c increased from 14.73 MPa to 22.76 MPa between 7 and 28 days, showing a percentage increase of 54.5%. Concrete made with BACA (M 20 BACA) demonstrated a similar progression, with f c rising from 14.80 MPa to 23.11 MPa between7 and 28 days, reflecting a percentage increase of 56.0%. This indicates a slightly higher increment in strength for the BACA mix compared to the M 20 concrete with CCA. For the M 25 grade concrete, the f c increased from 19.21 MPa to 30.3 MPa between 7 and 28 days, representing a percentage increase of 57.7%. The M 25 concrete with BACA (M 25 BACA) exhibited a similar trend, with f c progressing from 19.36 MPa to 31.8 MPa between 7 and 28 days, showing a percentage increase of 64.2%. This indicates a slightly higher percentage increment in strength for the BACA mix compared to the CCA mix (Wongsa et al., 2016; Park et al.,2022) .

Fig.2. Compressive strength of various mixes

4.2 Split Tensile Strength (fsts) of CC with CCA and BACA

The f sts of the concrete mixes, both with CCA and BACA, was evaluated at different curing intervals, as shown in Table 5. For the M 20 grade concrete, the f sts increased from 2.74 MPa to 3.15 MPa between 7 and 28 days, as illustrated in Fig.3. The concrete mix with BACA (M 20 BACA) exhibited a slightly higher progression, with f sts rising from 2.85 MPa to 3.37 MPa between 7 and 28 days, resulting in a percentage increase of 18.3%. This indicates a higher improvement in f sts for the BACA mix when compared to the CCA mix. For the M 25 grade concrete, the f sts increased from 2.96 MPa to 3.55 MPa between 7 and 28 days, reflecting a percentage increase of 19.9%. The M25 concrete with BACA (M 25 BACA) exhibited a higher increase, with f sts progressing from 3.04 MPa to 3.68 MPa between 7 and 28 days, showing a percentage increase of 20.9%.