# A Study on the Impact of Low-Frequency Random Loading and Unloading on Silo Structures
## 1 Introduction
When the temperature decreases, the actual increased pressure value exceeds the calculated value given by European specifications. [PERSON] et al. [7] used finite element software to thoroughly analyze the stress distribution of giant reinforced concrete silo walls under two different conditions: empty and full. They paid special attention to the influence of temperature changes on the stress distribution. The results were compared with the stress distribution under the action of storage side pressure and analyzed in detail. [PERSON] et al. [8] conducted an in-depth analysis of the stress state of concrete silo walls under the influence of internal and external temperature differences. Their research results showed that there is a linear relationship between temperature effects and multiple parameters, including internal and external temperature differences, elastic modulus, and silo wall thickness. This article focuses on the cracking problem of silos after the implementation of an anti-cracking design according to specifications. Through simulating the impact of material loading and unloading on silo performance using the finite element software Abaqus 2022, the study found that under different loading conditions, the silo wall experiences uneven forces, resulting in significant bending and torsional moments. This causes excessive local tension, leading to eccentric stress and silo wall cracking. The study also identifies the most unfavorable material loading method as guidance for practical engineering. However, the generation of this eccentric stress is a dynamic loading process. Under the cyclic action of loading and unloading, the silo wall experiences varying degrees of fatigue damage, which can reduce the safety of the silo structure. To ensure the safe use of silos and provide a technical basis for silo wall reinforcement or demolition and reconstruction, it is necessary to analyze the fatigue performance and fatigue life of reinforced concrete silos. Currently, for the fatigue analysis of reinforced concrete structures, [PERSON] et al. [9] have established a corrosion fatigue life prediction model for reinforced concrete structures under the coupled effects of a chloride salt erosion environment and fatigue loading. This model not only considers the impact of fatigue loading on the corrosion rate of steel bars but also takes into account the accelerating effect of steel corrosion on the accumulation of fatigue damage, thus improving the accuracy in predictions of corrosion fatigue life. Through parametric analysis, the effects of the crane lifting mass, operating frequency, and environmental levels of chloride salt erosion on fatigue damage and corrosion fa tigue life are discussed in detail, providing valuable guidance for engineering design and maintenance. [PERSON] [10] established equations for the fatigue residual strength envelope of concrete and steel bars and proposed a comprehensive analysis method for fatigue damage accumulation and failure. The reliability of this method was verified through examples, enabling a more effective evaluation of the fatigue life and safety of bridges. [PERSON] et al. [11], based on practical bridge engineering, proposed a numerical analysis method specifically targeting the fatigue failure process of reinforced concrete bridge decks in highways. This method simulates the fatigue damage degradation process of the bridge deck under vehicle loads, providing a new means for evaluating the fatigue performance of bridge decks. [PERSON] et al. [12] conducted fatigue tests on U-beam steel-reinforced concrete beams, verifying the accuracy of the Fe-safe fatigue life prediction. [PERSON] et al. [13] used Abaqus to establish a finite element model to study the fatigue damage characteristics of concrete beams under static, multi-level, and random loading conditions. [PERSON] [14] used Abaqus combined with Fe-safe 2023 software to study the effects of factors such as concrete strength and fatigue load levels on the bending fatigue life of reinforced concrete beams. [PERSON] et al.