Introducing Effective Microorganism as Self-curing Agent in Self-cured Concrete

Abstract

The primary reason for the curing of concrete is to complete the hydration reactions of cement with other materials. However, the problem occurs when required ideal curing becomes challenging due to various anomalous structural elements. To mitigate this issue, a bacterial solution known as Effective Microorganism (EM) has been introduced as a self-curing agent that has favourable surface tension, viscosity and solubility in water. Different percentage of water i.e. 0%, 5%, 10%, 15%, 20%, and 25% were replaced with EM. The optimisation of percentage replacement of EM was based on the compression strength and water loss of concrete. The percentage of EM with 10% water replacing showed better compression strength as compared to other percentage replacements. With the optimum 10% percentage, compression strength was found 42 MPa and 49 MPa compared with 33 MPa and 43 MPa with control samples with air and water curing respectively. The water loss also reduced 2% with 10% EM replacement compared to the control sample. Results showed that 10% of EM is the optimum value to get desirable properties of concrete in air and water curing. EM can be used as a new self-curing agent as a novel approach in the area of self-curing concrete.

A Review on the Use of Self-Curing Agents and Its Mechanism in High-Performance Cementitious Materials

“…As a result, the technique has been readily introduced where water-filled internal curing agents acting as reservoirs are added to the concrete mixture which will gradually release water during hydration and evaporation process [31][32][33][34], as illustrated in Figure 2. High-performance concrete (HPC) mixtures were initially developed given the growing issues regarding concrete durability [35,36] and due to the use of lower water-cementitious (w/c) material ratios, in addition to chemical admixtures and supplementary cementitious material (SCMs). Measuring the extent of hydration in the cementitious system is a key indicator that leads towards achieving the good performance of the concrete [37].…”

“…Many researchers reported SAP improving the compressive strength [32,36,42,80,107,153] of high-performance concrete. However, some of the compressive strength decreased as greater amounts of SAP were added to the concrete [53,[154][155][156][157][158], as shown in Table 1.…”