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.

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.

A survey and assessment of the technical condition of basement and semi-basement structures in public buildings aged 60 to 130 years were conducted to evaluate their suitability for use as basic shelters. Based on the survey results, the most adverse impacts were identified, including changes in groundwater levels, improper building operation, and the characteristic damages to underground structural elements. Structural solutions were proposed to eliminate the consequences of these damages. The reviewed cases indicate that the vertical and horizontal waterproofing systems used during construction cannot perform their function throughout the building's entire life cycle. When designing new buildings, waterproof materials should be used for the enclosing structures of underground premises. While this may have a higher initial cost than membrane or coating waterproofing, considering life-cycle costs, it can provide a positive economic effect and improve the quality and comfort of the indoor environment.