Concrete Mix Design for Service Life of RC Structures under Carbonation Using Genetic Algorithm

Table 3

Summary of test setup [14].

Steps
(a) Installation of test equipment in room (20°C)
(b) Measurement of concrete sample thickness and diameter
(c) Installation of sample (concrete disk) in cell
(d) Applying N2 gas and CO2 gas to different cells with same pressure
(e) Measurement of CO2 concentration when CO2 concentration in N2 gas keeps constant (steady state)
𝐷CO2=𝑄𝑓CO2𝐿(1−𝑓CO2)𝐴
𝐷CO2: diffusion coefficient of CO2; 𝑄: flow rate of gas
𝑓CO2: mol fraction in N2 + CO2; 𝐿: thickness of disk; 𝐴: area of disk