Chloride Diffusion Coefficient Research Articles

Performance of limestone calcined clay cement (LC3) incorporating low-grade marine clay

Clay is a globally abundant material and can potentially be used as a cement substitute after calcination. Though kaolinitic clay exhibits notable reactivity, the potential of low-grade clay with relatively low kaolinite content remains underexplored. This study comprehensively analyzed the chemical and mineralogical composition of marine clays at various locations and depths in Singapore, assessing their feasibility for preparing limestone calcined clay cement (LC3). The hydration kinetics and microstructure development of LC3 pastes, incorporating calcined marine clay, were investigated by XRD, isothermal calorimetry, SEM, and MIP. Additionally, a mini-migration test was employed to investigate chloride ion diffusion in LC3 pastes. The results revealed that Singapore marine clays contain relatively low kaolinite content (16–20% by QXRD). Despite a 25% reduction of 28 days compressive strength compared to reference OPC, LC3 samples exhibited outstanding resistance against chloride penetration regardless of kaolinite content (<40%) or replacement level (LC3-70 or LC3-50). The chloride diffusion coefficient (LC3-50) is one order of magnitude lower than the OPC system. Overall, our findings broaden the selection of raw materials for LC3 preparation and underscore the robustness of LC3 to resist chloride penetration, irrespective of variations in the clay's quality or source.

Effects of different cooling methods on the resistance to chloride ion penetration in concrete produced with slag-modified cement and exposed to elevated temperatures

The deterioration of reinforced concrete elements is associated with the ingress of aggressive agents through the concrete capillary pores. The exposure to elevated temperatures can be a serious concrete degradation factor, depending on its intensity and the cooling procedures. This paper presents a quantification of the effects of slow cooling (SC) and fast cooling (FC) methods on the chloride-ions penetration into fire-damaged concretes produced with a slag-modified cement. A (2 × 4 × 2) factorial experimental program was designed to evaluate the diffusion of chloride ions within different types of concrete (characteristic compressive strengths of 20 MPa and 35 MPa) before (25 °C) and after exposure to different high temperature levels (200 °C, 500 °C and 700 °C) and cooling procedures (SC and FC). Chloride diffusion coefficients were used to estimate the service life of the concretes and scanning electron microscopy was used to investigate the microstructural mechanisms behind the durability results. The exposure of concrete to high temperatures compromises its durability, as thermal cracking propagation and porosity increases tend to facilitate the penetration of aggressive agents and the diffusion of chloride ions. The use of the slag-modified cement did not provide significant benefits to the durability of concretes exposed to 200 °C and the effects of different cooling methods on the chloride ions permeability were very noticeable. In contrast, statistical analyses did not detect significant difference between the effects of SC and FC for concretes exposed to 500 °C or 700 °C.

Similarity analysis of chloride transport behavior in fly ash concrete under different environments aiding by machine learning method

To forecast chloride transport in site by applying accelerated test results, it is necessary to investigate the similarity of chloride diffusivity under different environments. However, limited by test period and cost expenses, a large amount of tests in field and simulated environment are hard to conduct, and a limit test data will make prediction on chloride diffusivity of concrete less precise. To solve this problem, machine learning methods are explored to predict chloride transport. Based on the existing chloride concentration test data of fly ash concrete in natural and accelerated simulated environment, this paper establishes a chloride concentration predictive model based on the one-dimensional convolutional neural network (1D-CNN) method at first, and verifies the stability and accuracy of the established model. Second, similarity models for concentration ratio and diffusion time ratio based on multivariate nonlinear model and based on theoretical Fick’s second law are constructed, and the model accuracy is also tested. Finally, the chloride concentration data predicted by the 1D-CNN model is applied to the constructed similarity models respectively, and the application results are compared and analyzed to determine the optimal similarity model. Results indicate that the concentration predicted by the 1D-CNN method has a strong robustness and a small prediction error. Besides, based on multivariate nonlinear model, the error of concentration predicted by the similarity models for concentration ratio and diffusion time ratio is less than 16% and 30%, respectively. Similarly, according to the theoretical model based on Fick’s second law, the error of concentration predicted by the similarity models for concentration ratio based on the time dependent chloride diffusion coefficient and time dependent peak chloride concentration is less than 21% and 36%, respectively. The similarity model for concentration ratio based on multivariate nonlinear model has the best prediction effect.

Time-dependent concrete chloride diffusion coupled with nonlinear chloride binding: An analytical study

Both the temporal dependence of chloride diffusion coefficient and the effect of nonlinear chloride binding substantially affect the behavior of concrete chloride diffusion. This study develops an exact chloride diffusion solution that accommodates the above two factors by introducing a simplified but reasonably realistic nonlinear chloride binding isotherm. The introduction of this isotherm makes it possible to achieve an analytical solution to a highly nonlinear chloride diffusion equation that involves a free chloride concentration dependent dimensionless factor which reflects the effect of chloride binding. First, a time-dependent chloride diffusion model incorporating the introduced isotherm is established with the corresponding exact solution derived. The proposed solution is successfully validated against two existing analytical solutions and a numerical solution. Parametric study is conducted using the proposed solution to investigate how the parameters regarding chloride ingress influence the corrosion initiation time, and results show that the increase of the initial effective chloride diffusivity or the before-ingress age decreases the corrosion initiation time bringing an acceleration of a different level to chloride diffusion while the increase of the age factor prolongs the corrosion initiation time decelerating chloride diffusion to some extent, and as each of the three nonlinear chloride binding associated parameters (i.e., the deflection-point concentration, the former slope and the latter slope) increases, the corrosion initiation time rises and the retardation effect on chloride diffusion is enhanced to a various extent. Lastly, to demonstrate the practical validity of the proposed solution, the solution is applied to reproducing a reported chloride diffusion test, and it turns out that our solution reproduces the diffusion test reasonably well, justifying its practical validity.

Investigation on chloride releasing from coral aggregates to cement paste in coral aggregate concrete

Coral aggregate concrete (CAC) is one of the most commonly used building materials in construction on marine islands, but the chlorides contained in the coral aggregates (CA) could affect the durability of CAC with steel bars embedded. In this paper, an analytical solution for the diffusion of chlorides from CA into the cement paste in CAC was derivated and the model was established. Studies on chloride releasing behaviours in CAC through an experimental setup of CAC interface specimens with five mixes were conducted. From the analytical model, the chloride diffusion coefficient DCl can be obtained and, different from other reported chloride diffusion coefficient from harden specimen, this coefficient could be the only factor that describes the chloride transport in CAC from the mixing stage. The chloride releasing rate αCl from CA was also calculated and quantified. The results show that the chloride release rate from CA decayed with time and significant chloride release occurred in the first 30 days from the mixture of raw materials, the released amount of chlorides from CA was positively correlated to the average pore size of cement pastes, and the chloride diffusion coefficient of CA in this study was 2–3 magnitudes higher than that of hardened cement paste.

Time-dependent reliability assessment and optimal design of corroded reinforced concrete beams

It remains a significant challenge to quantitatively describe the corrosion of reinforced concrete (RC) structures under chloride penetration. Moreover, when considering uncertainties throughout the life cycle of corroded RC structures for assessing their safety, reliability, and optimal design, the complexity of the problem intensifies. To address these issues, this paper studies the time-dependent reliability analysis and optimal design of corroded RC beams. At first, the time-dependent reliability of beams is investigated by considering both the serviceability limit state (SLS), which corresponds to the corrosion initiation of the reinforced steel, and the ultimate limit state (ULS), associated with the bending failure of the beam. This analysis takes into account the time-dependent chloride diffusion coefficient and incorporates a stochastic process. The reliability is evaluated using the Monte Carlo Simulation (MCS) method and the cumulative distribution function (CDF) method. Subsequently, a time-dependent reliability-based design optimization (TRBDO) problem is formulated, and the PSO-MCS, a methodology incorporating a particle swarm optimization (PSO) algorithm and MCS is adopted to solve it. After optimization, the initial cost of the specific RC beam is reduced from 1351.879€ to 1247.075€, while the time-dependent reliability within [0, 100] years is improved from 0.6057 to 0.6508. The effectiveness of the CDF, MCS and PSO-MCS methods are demonstrated through reliability analysis and design examples of corroded RC beams.

Convection-diffusion-electromigration coupled numerical simulation of water and chloride in cement-based materials

The transport of chloride in cement-based materials is influenced by various factors, and the chloride diffusion coefficient in numerical models should be the steady-state value under specific conditions, which is difficult to obtain through traditional experiments. In this article, based on an improved non-contact resistivity instrument, the steady-state chloride diffusion coefficient and porosity of cement-based materials are characterized. Considering the acceleration effect of moisture convection and electric field on chloride transport, a numerical model for moisture and chloride transport coupling diffusion, convection, and electromigration is established. Based on the measured steady-state chloride diffusion coefficient and porosity values, the influence of interface transition zone (ITZ), electric field type, chloride binding effect, initial conditions, and boundary conditions on moisture and chloride transport is numerically analyzed. It is found that the increase of ITZ thickness, electric field strength, boundary concentration, and initial concentration can accelerate chloride transport. The chloride concentration distribution curve exhibits a “shoulder peak” caused by chloride binding effect, and its peak height and width are positively correlated with the chloride binding coefficient. In conclusion, this study aims to better understand the ion transport behavior inside cement-based materials under coupling of convection, diffusion, and electromigration, and identify the key factors influencing this behavior, which provide a feasible scheme for durable design of concrete construction in environments rich in erosive media.

Resistivity and chloride diffusion coefficient of cement-based materials characterized by non-contact electrical resistivity method and resistivity model

The present study involves the application of the non-contact electrical resistivity measurement (NC-ERM) as a non-destructive method to continuously and in-situ measure the resistivity changes of cement-based materials. The NC-ERM was enhanced and utilized to evaluate the resistivity of the materials, and the steady-state chloride diffusion coefficients of various types of cement-based materials were experimentally determined. The results revealed that the highest resistivity was observed in mortar with a sand-to-cement ratio of 1.0 and concrete with an aggregate-to-cement ratio of 0.6, and the steady-state chloride diffusion coefficient increased with the concentration of the pore solution. Furthermore, a novel multi-level series-parallel model was developed to predict the resistivity and steady-state chloride diffusion coefficient of cement-based materials, with calculated values differing by 5% or less. The calculated chloride diffusion coefficient closely matched the value obtained from NC-ERM, indicating the satisfactory accuracy of the non-destructive experiment and theoretical calculation model.

Steel corrosion and critical chloride content in concrete with calcined kaolinite clay, fly ash, and limestone powder under natural and accelerated marine environments

This study aims to investigate steel corrosion and critical chloride content in concrete with calcined kaolinite clay, fly ash, and limestone powder. The chloride diffusion coefficient and compressive strength of concrete, and weight loss of steel were measured after the specimens were exposed to the tidal zone in a real sea environment for 1 and 2 years. The depassivation time of the embedded steel and the critical chloride content of the concrete under an accelerated marine environment were investigated in the laboratory. The test results revealed that the coefficient of chloride diffusion and critical chloride content of concrete and weight loss of steel decreased with increasing calcined kaolinite clay contents. Although utilizing calcined kaolinite clay in concrete mixtures reduced critical chloride content (0.655% by wt. of binder for OPC and 0.573 to 0.427% by wt. of binder for C15 to C45) because of the lower portlandite content, it caused a longer rebar depassivation time (46 days for OPC and 63 to 237 for C15 to C45). The ternary binder systems of cement, calcined clay, and fly ash demonstrated the best overall performances, i.e., the lowest chloride diffusion coefficient (0.29 ×10−12 m2/s) and the highest compressive strength of the concrete (38.7 MPa), and no weight loss of embedded steel at 2 years of exposure.

A Review of Chloride Penetration of Recycled Concrete with Enhancement Treatment and Service Life Prediction.

The application of recycled coarse aggregate (RA) in structural concrete can save non-renewable resources and reduce land occupation. Developing comprehensive knowledge of chloride penetration and service life modeling of recycled coarse aggregate concrete (RAC) is a prerequisite for practice. However, compared with the natural aggregate concrete (NAC), the inferior durability performance, especially chloride penetration resistance, of RAC hinders its application in structural concrete. Therefore, many RAC performance enhancement methods have been proposed. This paper presents a holistic review focused on the chloride penetration of RAC with/without enhancement methods and service life prediction. The current RAC performance enhancement methods are introduced. The improvement effect of the corresponding enhancement methods on the chloride penetration resistance of RAC are discussed and analyzed in turn. Based on the reviewed data on the chloride diffusion coefficient, the modification efficiencies of assorted enhancement methods are summarized. With the hope of promoting RAC application in structural concrete, the current literature on chloride-ingress-based service life prediction for RAC is also overviewed. In addition, the typical influencing factors on chloride transport properties are also discussed, i.e., RA quality. It can be concluded that enhancement techniques can effectively improve the chloride penetration resistance of RAC. The old mortar enhancement or removal methods can improve the chloride penetration resistance by 15-30%, depending on the specific treatment measures. The modification efficiency of the modifier material depends on the specific type and content of the incorporated substance, which ranges from approximately 5% to 95%. The estimated service life of RAC structures decreases with the increasing RA replacement ratio. Finally, concluding remarks are provided concerning future research on the chloride transport behavior of RAC.

Influence of hydraulic pressure on pore structure evolution and chloride transport in concrete

To study the influence of hydraulic pressure on pore structure evolution and chloride transport behavior in concrete, the mass transport depth, chloride concentration, and pore characteristics of specimens with different water-cement ratios were investigated using silver nitrate spraying, potentiometric titration, the mercury intrusion porosimetry (MIP) method, N2 adsorption method, and laser confocal microscopy. The results showed that chloride concentration increases as the hydraulic pressure and the water-cement ratio increase. As this hydraulic pressure increases, the difference between water and chloride ion transport distinctive characteristics becomes conspicuously pronounced, extending from 5.2 mm to 25.4 mm in distance. The hydraulic pressure changes the pore structure of the concrete, leading to a surge in the specific surface area, larger porosity, and average pore diameters. Notably, ink-bottle-type pores emerge prominently and the proportion of fine mesopores and capillary pores markedly rises after the application of hydraulic pressure. Furthermore, a relationship between chloride diffusion coefficient and hydraulic pressure is suggested. A relationship between the modified permeability coefficient and hydraulic pressure is constructed based on the mesoporous contribution β to express the hysteresis effect of chloride.

Mitigating CO2 emanations within the marine concrete industry with different structures of silica nanoparticles

The extensive utilization of marine concrete results in a significant consumption of cement, thereby leading to an increase in CO2 emanations. Enhancing the potency and longevity of marine concrete serves as an efficacious approach to mitigate CO2 emanations. The objective of this investigation was to introduce colloidal silica nanoparticles with distinct three-dimensional structures (MCM-41, SBA-15, and DFNS) for the purpose of enhancing the mechanical functionality and longevity of remarkable sulfate persistence Portland cement. Meantime, the incorporation of silica nanoparticles with distinct three-dimensional architectures (DFNS, MCM-41, and SBA-15) into marine cement mortar was carried out, and an investigation was conducted on the aggregation of silica nanoparticles, as well as the humidifying process and micro-process of the mortar. According to the findings, the addition of silica NPs improved the resilience, mechanical traits, and longevity of the marine cement cases. When the inclusion of silica nanoparticles with varying three-dimensional structures (DFNS, MCM-41, and SBA-15) was implemented, a decrease in both the chloride diffusion coefficient and porosity was observed. The compressive intensity of cement mortar was enhanced in the presence of DFNS, MCM-41, and SBA-15 when compared to control samples, following a rehabilitating period of 5, 15, and 30 days. These advancements in intensity and longevity suggest that DFNS exhibits considerable potential in mitigating CO2 emanations within the marine concrete industry.

Chloride diffusion behaviour and structural performance of basalt fiber- reinforced concrete beam in marine environment

For marine reinforced concrete structures exposed to saline water, the rate of penetration of chloride ions into concrete is crucial to their performance. To resist the chloride penetration within marine structures, the incorporation of basalt fibers into M40-grade concrete was pursued. The current research develops into two primary investigations. The first pertains to the determination of chloride penetration depths and the associated diffusion coefficients of concrete cubes, while the second focuses on the structural behaviour of basalt fiber-reinforced concrete beams under chloride diffusion. The chloride diffusion coefficients were determined using experimental methods for eight concrete cubes with varying proportions of basalt fiber (0%, 0.5%, 0.75%, and 1% v/v). These coefficients were subsequently validated through numerical methods, applying Fick’s law. Additionally, numerical techniques were employed to calculate chloride concentration and the corresponding flux at various diffusivity time intervals, leading to the development of corresponding chloride concentration equations. A corelation was developed in between chloride penetration depth, time period and dose of basalt fiber. The present model can be used as a tool for analysis to represent the real condition of concrete deterioration brought on by chloride action. In terms of examining structural responses, a comprehensive evaluation was conducted encompassing load deflection behaviors, crack propagation tendencies, and stress-strain analyses of concrete beams reinforced with basalt fibers. The stress block diagram had been modified by determining various stress block parameters (αandβ) of chloride diffused basalt fiber reinforced concrete beam under cyclic load.

Non-destructive characterization of pore structure and chloride diffusion coefficient of cementitious materials with modified non-contact electrical resistivity method

The intricate pore structure of cement-based materials passively influences chloride ion transport and mechanical properties. Existing non-contact electrical resistivity measurement (NC-ERM) methods lack precision for rigorous studies. the NC-ERM was upgraded in this research, which is suitable for assessing the pore structure and transport characteristics of hardened cementitious substrates. The results obtained from this method closely correspond to those obtained from CEMHYD3D, Mercury intrusion porosimetry (MIP), and other methods. Additionally, the impact of mixture proportions on the resistivity, pore structure parameters, and chloride ion diffusion coefficient of cementitious materials is discussed. With an increase in sand ratio and sand-to-stone ratio, the resistivity exhibits an initial rise followed by a decline. Chloride diffusion of 5wt% NaCl-saturated specimens is 1.2–1.3 times higher than 3.5wt% NaCl. This study provides a novel non-destructive, convenient and accurate method for characterising the pore structure and testing the transport properties of cementitious materials.

Assessment of self-healing performance of cement-based materials incorporating ion chelator and industrial wastes

Ion chelator can enhance the self-healing of cracks and pores in concrete. To further improve the self-healing capability of cement-based materials, different industrial wastes (i.e. fly ash, limestone powder and blast furnace slag (BFS)) and ion chelator were mixed into mortar. The crack closure index, water permeability, water absorption, impermeability, compressive strength recovery and healing products of mortar were studied. The results showed that the mortar mixed with BFS and ion chelator possessed the best repair ability on cracks, the crack with a maximum width of 0.55 mm can be closed within 14 d. Meanwhile, the water permeability and water absorption of mortar incorporating ion chelator and BFS were obviously smaller than that of control mortar. After curing for 56 d, the chloride diffusion coefficient of mortar containing ion chelator and BFS was reduced by 73.7% compared with control mortar. The compressive strength recovery ratio of mortar containing ion chelator and BFS was 63.7% greater than that of control mortar after pre-loading 80% of the failure strength. In addition, scanning electron microscopy and energy dispersive spectroscopy displayed a large number of calcites at the edge of crack section in mortar containing ion chelator and BFS, the inside of crack was mainly repaired by the combined effect of calcium carbonate precipitation and hydration product.

Compressive strength and chloride permeability of cement-based materials with high-volume compound mineral admixtures

Ground granulated blast-furnace slag (GGBFS) is well known to be capable of improving the performance of cement-based materials, but few studies focus on the impact of its large dosage on concrete containing basalt powder. In this study, the compressive strength and chloride permeability of cement-based materials with compound mineral admixtures (CMAs) containing high-volume GGBFS, basalt powder and desulfurisation gypsum were investigated. The results showed that the mortar strengths at 3, 7 and 28 days decreased with increasing GGBFS content, but that at 56 and 84 days increased with the addition of 45 wt% GGBFS. This is because the activity of GGBFS at an early stage has not been stimulated and the pozzolanic effect is exerted at a later stage. Moreover, cement replacement with up to 55 wt% GGBFS caused a significant decrease in the chloride diffusion coefficient of the mortar and concrete. Furthermore, the incorporation of GGBFS led to a remarkable refinement in pore structure of the hardened paste due to pozzolanic and filler effects. Therefore, the partial replacement of cement with high CMA contents (≥70 wt%) in concrete is desirable for ocean projects requiring low chloride permeability, and significantly reduces carbon dioxide emissions.

Experimental and Numerical Study on Chloride Transport in Unsaturated Concrete: Highlighting Temperature, Humidity, and Mineral Admixtures.

Chloride transport within concrete is critical for the durability of reinforced concrete structures; however, its diffusion under the coupling action of temperature and humidity has not been fully comprehended. Therefore, in this work, the coupling effects of temperature, relative humidity, and mineral admixtures on chloride transport in concrete were investigated through experimental and numerical simulation work. The results show that the chloride diffusion coefficient decreases with the decreased temperature and growth of relative humidity; however, the chloride concentration on the concrete surface is increased with the growth of temperature and relative humidity. Moreover, compounding about 15% fly ash (FA) and 30% granulated ground blast furnace slag (GGBS) to replace the cement is the most beneficial for improving the antichloride capacity of concrete, considering also the strength. In addition, the numerical simulation considering the coupled effect of temperature and relative humidity of chloride transport in concrete has good agreement with that of experimental results.

Increasing service life of concrete in sewage treatment plants using silica fume and natural zeolite

Microbial attacks rapidly degrade concrete structures in wastewater facilities, leading to brief service lifespans. Hence, producing concrete resistant to chemical and sulfuric acid corrosion is more cost-effective. In the present study, a total of six concrete mixtures incorporating 7.5% silica fumes (SF) and 10% natural zeolite (ZE) were immersed in 0.5% and 1% sulfuric acid solutions with a maximum pH threshold of 2 and 1, respectively, for 70 weeks. The specimens were regularly monitored for surface deterioration, mass change and crushing load change. To better understand the relationship between the pore structure of concrete mixtures and resistance to sulfuric acid, various durability tests such as rapid chloride penetration, water absorption, electrical resistivity and chloride diffusion coefficient were performed. Based on the results obtained, converting calcium hydroxide into calcium silicate hydrate gel through pozzolanic reactions and then refining the porosity of concrete with silica fumes (SF) and natural zeolite (ZE) was effective in enhancing the resistance of concrete to attack by sulfuric acid of relatively low concentration. As a result, using silica fumes (SF) and natural zeolite (ZE) is a lower-cost method for reducing corrosion rates to extend the service life of facilities, particularly in lower concentrations.

Mesoscopic characteristics and spatiotemporal variability of chloride transport in concrete

Chloride-induced corrosion is the leading cause of structural performance deterioration and life decay in marine environments. This paper delves into the mesoscopic characteristics and spatiotemporal variability of chloride transport in concrete. We conducted extensive mesoscopic simulations to reveal the effects of ITZ and aggregate volume fraction, morphology, size, and particle quantity on chloride transport. We identified the probability characteristics of chloride concentration and diffusion coefficient based on statistical analysis of the mesoscopic simulation results. We proposed a novel probabilistic framework and predictive model for chloride diffusion coefficients incorporating aggregate parameters like volume fraction and particle size. The findings of this study demonstrate that the chloride transport shows noteworthy spatiotemporal variability; the aggregate size effect, aggregate particle quantity effect, and the local effect of large aggregates are all significant characteristics of the chloride transport in addition to the pre-discovered dilution effect, tortuosity effect, and ITZ effect. The chloride diffusion coefficient approximately follows a log-normal distribution, whereas the chloride concentration roughly follows a normal or log-normal distribution. The findings in this work are instrumental in predicting the probabilistic chloride transport and service life of reinforced concrete structures.

Advancing service life estimation of reinforced concrete considering the coupling effects of multiple factors: Hybridized physical testing and machine learning approach

Chloride-induced corrosion is the primary factor that significantly impacts the service life of reinforced concrete structures. Therefore, it is crucial to investigate the transportation behavior of chloride ions within concrete structures to accurately estimate their service life. Previous studies have mostly examined the diffusion of chloride ions through physical tests on concrete specimens. Some data-driven models have also been developed to predict the chloride ion concentration at different depths in concrete structures. However, these prediction models often considered random factors in materials and the environment separately, neglecting their coupled effects. As a result, there can be a significant disparity between the predicted results and the actual test outcomes. To achieve a more precise evaluation of the service life, this study conducted a physical test to investigate the diffusion behavior of chloride ions in plain concrete specimens. Factors such as water-cement ratio (W/C), coarse aggregate volume fraction (v) (ratios of the mass of coarse aggregates to the total mass of concrete specimen), ratios of environmental temperature to maintenance standard temperature (T/T0), ratios of environmental humidity to maintenance humidity (h/h0), and ratios of exposure time to maintenance time (t/t0) were considered in the test. Based on the test results, machine learning approaches were employed to determine the influence of each factor on the chloride diffusion coefficient (D) and surface chloride concentration (Cs). Subsequently, a prediction model was developed using the second Fick's law, with the chloride ion concentration at each depth as the output and the aforementioned factors as the inputs. Furthermore, by analyzing the above results, the study examined the impacts of various factors on the service life of reinforced concrete structures. The findings indicate that W/C and v are the most significant factors affecting D and Cs. As W/C and T/T0 increase, both D and Cs also increase. Conversely, the volume fraction of coarse aggregate has a hindering effect on the diffusion of chloride ions in concrete structures. Additionally, the study explored the effect of each input factor on the service life of reinforced concrete structures considering the effect of the above factors. Overall, these findings provide valuable insights into improving the accuracy of estimating the service life of reinforced concrete structures by considering the coupled effects of materials and environmental factors.