This paper investigated the influence of chloride ion erosion and aftershocks on the seismic performance of transmission tower structures in Xinjiang, China. Based on chloride ion diffusion laws and steel corrosion mechanisms, the time-dependent deterioration of reinforced concrete was analyzed. Finite element models considering corrosion effects were established for different ages(0a,50a,70a,100a) in a saline soil environment using ANSYS/LS-DYNA. Ten mainshock-aftershock sequences tailored to the site type was constructed, and the cumulative damage index (DI) was adopted as a metric for structural damage. The results indicate that aftershocks and steel corrosion significantly impact transmission tower damage, with damage extent influenced by the intensity of the main shock. Stronger aftershocks cause greater additional damage, potentially exceeding 50 % cumulative damage when their amplitude matches the main shock. Steel corrosion alone can lead to nearly 40 % damage. Its influence on seismic fragility varies with damage state, especially under moderate to complete damage, where longer service life increases vulnerability. The coupling of corrosion and aftershocks further elevates structural vulnerability. Hence, in seismic assessments of transmission towers in saline soil environments, combined effects of main and aftershocks, and corrosion, must be accounted for.

Stray currents can cause electrochemical corrosion of metals, accelerate material aging, and even pose safety hazards. By studying corrosion behavior and speed, the degree of damage caused by stray currents to metals can be evaluated, protective measures (cathodic protection, insulation design, etc.) can be optimized, the service life of metal structures can be extended, maintenance costs can be reduced, and the safe and stable operation of power systems and infrastructure can be ensured. Therefore, research on the electrochemical corrosion behavior and velocity analysis method of metals under AC stray current. This article mainly explores the influence of different alternating current (AC) stray current densities on the electrochemical corrosion behavior of 316L stainless steel. The experiment used Yingtan soil simulation solution, and analyzed the changes in indicators through electrochemical testing, corrosion morphology observation, and corrosion rate calculation. The results indicate that the corrosion rate of 316L stainless steel in soil simulation solution shows a trend of first decreasing and then increasing when disturbed by AC stray current density. In the initial stage, the synergistic effect of high concentrations of Cl-and O2 leads to a faster corrosion rate. Over time, corrosion products increase and form a film layer, which hinders harmful ion erosion and slows down the corrosion rate. However, after prolonged immersion, the corrosion product film may crack, crevice, or even peel off, causing crevice corrosion and galvanic corrosion, accelerating the corrosion process. AC stray current forms a tip discharge through the defect, further exacerbating corrosion. With the increase of AC interference current density, the corrosion rate of 316L stainless steel significantly increases, and the main corrosion form changes from uniform corrosion to localized corrosion. When the stray current density is greater than or equal to 200 A/m2, the corrosion degree of 316L stainless steel under the peeling coating reaches severe corrosion. This study is of great significance for understanding the impact of AC stray currents on metal corrosion and developing effective protective measures.

In this essay, by summarizing the research progress and achievements of various scholars at home and abroad in recent years on the material properties and corrosion resistance of magnesium phosphate cement (MPC), we review the factors influencing on the properties of MPC, and analyze the effects of raw materials, retarders, and admixtures on the properties of MPC. Two different hydration mechanisms of MPC are discussed, and finally the research progress of MPC in the field of anti-corrosion coatings for steel and ordinary concrete (OPC) is highlighted, and suggestions and prospects are given.

Tunnel lining structures, which are subjected to the combined effects of water and soil pressure as well as a water-rich erosion environment, undergo a corrosion-induced damage and degradation process in the reinforced concrete, gradually leading to structural failure and a significant decline in service performance. By introducing the Cohesive Zone Model (CZM) and the concrete damage plastic model (CDP), a three-dimensional numerical model of the tunnel lining structure in mining method tunnels was established. This model takes into account the multiple effects caused by steel reinforcement corrosion, including the degradation of the reinforcement's performance, the loss of an effective concrete cross section, and the deterioration of the bond between the steel reinforcement and the concrete. Through this model, the deformation, internal forces, damage evolution, and degradation characteristics of the structure under the effects of the surrounding rock water-soil pressure and steel reinforcement corrosion are identified. The simulation results reveal the following: (1) Corrosion leads to a reduction in the stiffness of the lining structure, exacerbating its deformation. For example, under high water pressure conditions, the displacement at the vault of the lining before and after corrosion is 4.31 mm and 7.14 mm, respectively, with an additional displacement increase of 65.7% due to corrosion. (2) The reinforced concrete lining structure, which is affected by the surrounding rock loads and expansion due to steel reinforcement corrosion, experiences progressive degradation, resulting in a redistribution of internal forces within the structure. The overall axial force in the lining slightly increases, while the bending moment at the vault, spandrel, and invert decreases and the bending moment at the hance and arch foot increases. (3) The damage range of the tunnel lining structure continuously increases as corrosion progresses, with significant differences between the surrounding rock side and the free face side. Among the various parts of the lining, the vault exhibits the greatest damage depth and the widest cracks. (4) Water pressure significantly impacts the internal forces and crack width of the lining structure. As the water level drops, both the bending moment and the axial force diminish, while the damage range and crack width increase, with crack width increasing by 15.1% under low water pressure conditions.

This study investigates the corrosion behaviour of grounding down leads in transmission towers subjected to wet-dry cycle in saline soils of Northwest China through accelerated corrosion experiments. Using saline soil from the Hexi Corridor, rich in chloride and sulphate ions, corrosion rates were assessed via weight loss, polarisation curves, scanning electron microscopy and X-ray diffraction analyses. Results demonstrate that wet-dry cycle significantly accelerates corrosion due to enhanced chloride ion diffusion and corrosion kinetics, with the highest average weight loss rate (3.08%) and corrosion current density (0.3526 mA/cm(2)). Scanning electron microscopy analysis revealed extensive cracking in corrosion product layers under cyclic wet-dry conditions, weakening their protective capability and further intensifying corrosion. The primary corrosion products identified were FeO and Fe2O3, consistent with field samples, indicating that the corrosion mechanism remains unchanged under accelerated conditions. This study provides novel insights into how cyclic moisture conditions affect grounding materials in saline environments, guiding material selection, maintenance strategies and site selection to improve transmission line reliability and safety.

The influences of NO3- concentration and AC density on corrosion resistance of FeCoNi high entropy alloy in simulated saline-alkali soil solution were studied via a series of measurements. Related results imply that the anticorrosion property of the HEA is significantly improved with the increase in NO3- concentration, particularly at high concentration of 0.1 mol/L, and the passive film covering the HEA becomes dense, intact and uniform. NO3- as a protective barrier is absorbed on the film surface, significantly inhibiting the pitting corrosion of the HEA. As AC density rises, the HEA surface status evolves from passivation to activated state, presenting a serious overall corrosion feature. The AC application facilitates the damage of passivation film grown on the HEA, resulting in a rapid increase in the number of flaws, which remarkedly decreases its resistance capacity against corrosion. Furthermore, under the combined influence of the two factors, the adverse effect of AC interference is obviously larger than the positive impact of NO3- on the corrosion resistance of the HEA at i(AC) of 50 A/m(2), causing plentiful defects within the passive film and severe corrosion of FeCoNi HEA.

This research investigates a methodology for probabilistic life prediction of buried steel pipelines subjected to external corrosion. A unified methodology is developed considering multiple stages of degradation related to external corrosion (due to soil) and fatigue. These stages include corrosion pit nucleation, pit growth, transition from pit to short crack, short crack growth, transition from short to long crack, stable long crack growth, and unstable fracture. The methodology is useful in obtaining stage-specific forecasts for the fatigue life of buried steel pipelines subjected to external pitting corrosion fatigue. State-of-the-art computational models are used to predict damage initiation and evolution at each stage. The variability in environmental, material, and loading parameters is propagated through these models to obtain a probabilistic estimate of the remaining service life (RSL) of the pipe. Insights from probabilistic RSL prediction highlight the influence of soil type and pipe coating material on corrosion fatigue life. Global sensitivity analysis is then employed to quantify the relative importance of environmental factors (pH, pipe/soil potential, and chloride concentration), material properties (threshold stress intensity factor), and the range of cyclic stress experienced by the pipe.

The relevance between microstructure and anti-corrosion performance of FeCoNi HEA prepared with different cooling methods was studied in simulated Golmud salinized soil solution. The results reveal that the corrosion rate reduces with increasing cooling rate, and the water-cooling HEA has the best anti-corrosion performance, followed by the air-cooling and furnace-cooled samples, which mainly depends on the grain size and the protectiveness of passivation film. An increase in grain size weakens the micro-galvanic corrosion effect between the grain boundary and the internal grain. Moreover, compact and uniform passive film markedly improves the anti-corrosion performance of water-cooled HEA. Combined with electrochemical tests, the water-cooling HEA exhibits the lowest sensitivity of metastable and stable pitting, as well as its surface passive film possesses excellent self-repairing ability. In addition, the HEA substrate occurs the preferential dissolution of Ni element.

Subway station structures near coast are at risk of corrosion caused by chloride, resulting in material and structural component deterioration over time and impacting overall performance during earthquakes. This study proposes a numerical framework for the time-dependent seismic fragility analysis of subway station structures, considering chloride-induced corrosion, based on the IDA method. This study utilizes finite element simulations of typical subway station structures in Qingdao, Shandong, China, focusing on nonlinear dynamic interactions between soil and structure, as well as the impact of chloride-induced corrosion on aging effects. The time- dependent damage states within subway station structures are determined through a nonlinear static pushover analysis. Subsequently, the IDA method is employed to generate time-dependent seismic fragility curves and surfaces specific to subway station structures. The numerical results indicate that the impact of chloride-induced corrosion on the subway station structure cannot be ignored. In the corrosion environment, the seismic performance assessment of subway station structures must take into account time-dependent damage states resulting from the degradation of material properties and the reduction in seismic capacity. The probability of a subway station structure exceeding various damage states monotonically increases during its service life. The subway station structure primarily suffers minor to moderate damage under the ground motion with a return period of 2450 or 10000 years, as it reaches its design service life.

The advancement of green energy batteries as alternative energy sources is crucial for addressing the issues posed by hazardous chemicals and their disposal, thereby mitigating environmental damage caused by direct or indirect impacts of pollution. Recently, novel Earth Battery Systems (EBS) have been investigated, utilizing various types of soils, compost, and electrodes, with water as a fixed electrolyte. In this study, EBS are characterized using multiple techniques, including Linear Sweep Voltammetry (LSV) and Electrochemical Impedance Spectroscopy (EIS). Our findings reveal that, compared to soil-based earth batteries - which exhibit high impedance values, the open-circuit voltage (Voc) and short-circuit current (Isc) are significantly enhanced in vermi-compost-based earth batteries fabricated using steel-201 as the anode and graphite as the cathode. Furthermore, the critical role of organic matter in promoting ion transport and enhancing the system's overall efficiency is demonstrated through Cyclic Voltammetry (CV) and Ionic conductivity analysis. To ensure the sustainability of electrodes within the earth battery, corrosion studies are conducted using Tafel analysis. The results indicate that electrode corrosion can be effectively controlled by the strategic selection of corrosion inhibitors. Thus, this work lays the foundation for developing efficient, durable, and environmentally friendly EBS systems using soil and compost.