## 1 Introduction  
Capitalizing on strategic Chinese initiatives such as the Beibu Gulf City Cluster, Guangdong-Hong Kong-Macao Greater Bay Area, Hainan Free Trade Zone, and the pivotal position of the Belt and Road initiative, Zhanjiang, China, has experienced significant economic growth in recent years. The city's expansion and burgeoning population have prompted a surge in large-scale construction projects, including housing and rail transit. Numerous infrastructure and economic projects are founded on the Zhanjiang Formation structural clay. Frequent construction activities, including pile foundations and excavation pits, disturb the surrounding soil to varying degrees. Zhanjiang Formation structural clay, characterized by its strong structure and high sensitivity, is highly susceptible to changes in soil structure and sudden decreases in strength, which can lead to various engineering problems [1; 2]. Investigating the patterns and mechanisms of disturbance impacts on Zhanjiang Formation structural clay has emerged as a critical area of research. [PERSON] [3] examined the geotechnical properties of Zhanjiang clay and associated disturbance-related issues, revealing that undisturbed clay with strong structure displays a pronounced structural yield stress exceeding the overlying effective stress. [PERSON] et al. [4] investigated the effect of the disturbance degree on the thixotropic properties of Zhanjiang Formation structural clay. They concluded that the disturbance duration of soil is positively correlated with its disturbance degree. They found that, at a constant disturbance degree, both the extent of strength recovery and the proportion of thixotropic strength recovery increase with rest duration, whereas thixotropy sensitivity diminishes over time. [PERSON] et al. [5] performed experiments to assess the dynamic characteristics of Zhanjiang Formation structural clay under cyclic loads, finding that the clay demonstrates brittle failure under such conditions. While these studies offer essential insights into the engineering consequences of disturbances on Zhanjiang Formation structural clay, they are limited to the effects of disturbance on soil structure. However, investigating from the characteristics of disturbance sources may enable a more in-depth exploration into the effects of disturbances on the mechanical properties of the Zhanjiang Formation structural clay at the fundamental level, providing theoretical references for disturbance prevention in foundation soils. While [PERSON] [6] and [PERSON] et al. [7] have investigated the compression characteristics of soft soil based on vibration duration and vibration frequency, concluding that vibration duration-frequency significantly affects the compression deformation characteristics of soft soil, [PERSON] [8] and [PERSON] et al. [9] have established the relationship between vibration duration and the disturbance degree for evaluating soil disturbances. However, these studies have not conducted a comparative analysis of how vibration frequency and vibration duration, as disturbance factors, impact the mechanical properties of structural clay. Indeed, both vibration frequency and vibration duration influence the source of disturbance, with higher frequencies or longer durations resulting in increased energy transfer and greater soil disturbance, thereby significantly altering its mechanical properties. The disturbance degree of soil describes both the state of deterioration and the associated changes in mechanical properties. Therefore, it is necessary to analyze the mechanical properties of the Zhanjiang Formation structural clay based on disturbance degree and study the impact of vibration frequency and vibration duration as disturbance sources on its disturbed mechanical properties. This paper focuses on Zhanjiang Formation structural clay as the subject of study.