PSI - Issue 70

Vijaya Sundravel K et al. / Procedia Structural Integrity 70 (2025) 485–492

487

of manufactured sand with a relative density of 2.62 and hydration capacity of 1.33%, while coarse aggregate was granite aggregates with a relative density of 2.67 and water absorption of 0.45%. OPC 53-grade was used, with a compressive strength of 59.83 MPa at 28 days. Zeolite had a volumetric mass of 2.24, a particle size distribution of 3.66, and a water uptake capacity of 0.3%. A range of testing equipment was utilized to evaluate the concrete samples. Compression capacity was measured using a Compression Testing Machine (CTM) as per IS 516:1956 Xu et al. (2020). 3. Experimental Investigation The chapter deals with the assessment of two interface bonding systems — sheet bonding and plate bonding — for the strengthening of concrete beams using CFRP Jakubovskis et al. (2020). Sheet bonding employs a wet lay-up process, which involves the application of a primer, saturant, and CFRP sheets directly onto the concrete surface Guzlena and Sakale (2021). In contrast, plate bonding utilizes pre-manufactured pultruded CFRP plates that are bonded to the concrete using specialized adhesives Sundravel et al. (2015). Both systems were subjected to experimental and numerical analyses to assess their structural performance, including their effectiveness in enhancing load-bearing capacity, resistance to debonding, and overall durability under varying loading and environmental conditions Sidiq et al. (2020). 3.1 Beam Preparation RCC beams were cast with dimensions of 10 cm × 20 cm × 150 cm and strengthened with CFRP sheets or plates at the tension face. Proper surface preparation, including cleaning and primer application, was ensured. FBG sensors were embedded at critical locations to monitor strain Khan et al. (2021). The table 1 below provides a comprehensive overview of the mix identifiers and their specific formulations for Conventional concrete with Microbial concrete.

Table 1. Mix identifier and Explanation Sl.No. Mix Identifier

Explanation

1. 2. 3. 4. 5. 6. 7. 8. 9.

SHM-CC Standard M30 Concrete

SHM-BC-01 M30 with 0.4% Bacillus Subtilis for SHM SHM-BC-02 M30 with 0.5% Bacillus Subtilis for SHM SHM-BC-03 M30 with 0.6% Bacillus Subtilis for SHM SHM-PC-01 M30 with 0.4 % of Bacillus Pseudomonas for SHM SHM-PC-02 M30 with 0.5 % of Bacillus Pseudomonas for SHM SHM-PC-03 M30 with 0.6 % of Bacillus Pseudomonas for SHM SHM-EC-01 M30 with 0.4% Escherichia Coli for SHM SHM-EC-02 M30 with 0.5% Escherichia Coli for SHM SHM-EC-03 M30 with 0.6% Escherichia Coli for SHM

10.

The control mix, designated as "SHM-CC," represents standard M25-grade concrete prepared without the inclusion of any bacterial additives Singh and Gupta (2020). Other concrete mixes were developed by incorporating different bacterial strains into M30-grade concrete at varying concentrations Vijaya Sundravel et al. (2020). In this study, three bacterial species were utilized: Escherichia coli (referred to as SHM-EC), Bacillus Pseudomonas (SHM-PC), and Bacillus Subtilis (SHM-BC). Each bacterial strain was added at concentrations of 0.4%, 0.5%, and 0.6% to evaluate their impact on the concrete's properties Sundravel et al. (2024). The table 2 below provides a comprehensive overview of the mix identifiers and their specific formulations with zeolite.

Table 2. Mix identifier and Explanation for MICP concrete using zeolite Sl.No. Mix Identifier

Explanation

1.

SHM-B1Z10

0.4% Bacillus Sps. with 5% Zeolite