Model Testing of Deformation in Fissured Expansive Soil Slopes under Load and Irrigation

Rosulundik Harbeichtuk^*
*Correspondence: Rosulundik Harbeichtuk, Department of Geoengineering, Universitat Politécnica de Valencia, 46022 Valencia, Spain, Email:

Keywords

Expansive soils • Slope stability • Soil deformation • Geotechnical engineering

Introduction

Expansive soils are prevalent in many regions worldwide, particularly in arid and semi-arid climates where they exhibit significant volume changes in response to fluctuations in moisture content. These soils, characterized by their ability to swell when wet and shrink upon drying, can create substantial challenges for civil engineering projects, especially concerning the stability of slopes and the integrity of structures built on or with these soils. The presence of fissures or cracks in expansive soils further complicates the situation. These fissures often develop due to the soil's inherent volume change behavior and can influence the soil's mechanical properties, such as shear strength and compressibility. Understanding how fissured expansive soils deform under different conditions is crucial for assessing slope stability and preventing potential failures. Model testing provides a valuable tool for exploring these behaviors in a controlled environment. By simulating various loading and irrigation scenarios, researchers can observe and analyze the deformation characteristics of fissured expansive soil slopes. This approach enables a detailed examination of how moisture variations and applied loads impact soil stability and deformation, providing insights that are challenging to obtain through field studies alone. This study aims to investigate the deformation characteristics of fissured expansive soil slopes under load and irrigation through model testing. By replicating real-world conditions in a laboratory setting, the research seeks to uncover critical factors influencing soil behavior and slope stability. The results are intended to enhance our understanding of expansive soil dynamics and inform the development of effective design strategies and mitigation measures for infrastructure projects involving these challenging soil types [1,2].

Literature Review

Expansive soils, also known as shrink-swell soils, are notorious for their significant volume changes in response to moisture variations. These soils can experience large expansions when saturated and considerable shrinkage upon drying. This behavior is primarily due to the presence of clay minerals, such as montmorillonite, which absorb water and swell. The volume change can lead to soil heaving, cracking and instability, particularly in slopes and embankments. Fissures in expansive soils introduce additional complexity to soil behavior. Fissures can alter the soil’s mechanical properties by changing its stress distribution and drainage characteristics. These cracks can influence the soil's strength and deformation properties, potentially exacerbating issues related to slope stability. Research demonstrates that fissures can create pathways for rapid water infiltration, leading to uneven moisture distribution and further instability. Model testing provides a means to study soil behavior under controlled conditions, offering insights that are difficult to obtain from field observations alone. Laboratory models can replicate various loading and moisture conditions to evaluate soil response. Techniques such as physical model tests, often performed in a geotechnical centrifuge, allow for detailed analysis of deformation and stability under simulated environmental conditions [3].

These models help in understanding how expansive soils deform under different scenarios and how fissures affect their stability. Irrigation and loading are two critical factors influencing the deformation of expansive soils. Irrigation can lead to increased soil moisture, which affects the swelling and shrinkage behavior of expansive soils. Loading conditions, such as the weight of structures or vehicles, can further exacerbate the deformation and stability issues. Research shows that the combination of loading and moisture variation can significantly alter the deformation characteristics of expansive soil slopes, highlighting the need for careful management in design and construction.Mitigating the effects of expansive soils involves various strategies, including soil stabilization, proper drainage design and moisture control. Techniques such as chemical stabilization, using lime or cement, can reduce soil expansiveness. Drainage systems designed to control moisture levels and prevent excessive swelling are also crucial for maintaining slope stability. Understanding the deformation characteristics through model testing can help in developing effective mitigation strategies tailored to specific site conditions [4].

Discussion

The model testing of fissured expansive soil slopes under loading and irrigation conditions provides valuable insights into the complex behavior of these soils. The deformation of fissured expansive soils is influenced significantly by both moisture content and applied loads. The model tests demonstrate that fissures in the soil exacerbate volume changes, leading to more pronounced swelling and shrinkage. This behavior is consistent with findings from previous studies, which show that fissures alter the stress distribution within the soil and can lead to greater deformation under varying moisture conditions. Irrigation introduces additional moisture into the soil, which increases its volume and can lead to more severe swelling. The model tests show that even moderate irrigation can cause noticeable deformation in fissured expansive soils. This aligns with research indicating that moisture variations play a crucial role in the behavior of expansive soils [5].

The application of loads further impacts soil deformation, compounding the effects of moisture changes. The tests reveal that loading can lead to increased soil consolidation and additional cracking, exacerbating instability issues. This finding is supported by existing literature, which emphasizes the need to account for both loading and moisture conditions in the design of structures on expansive soils. The insights gained from model testing are critical for developing effective design and mitigation strategies. Understanding how fissured expansive soils deform under different conditions allows for better planning of drainage systems, stabilization methods and load management. Implementing appropriate soil stabilization techniques and moisture control measures can help mitigate the adverse effects of expansive soils and improve slope stability [6].

Conclusion

Model testing of fissured expansive soil slopes under loading and irrigation provides essential insights into the deformation characteristics of these challenging soil types. The study highlights the significant impact of fissures, moisture variations and applied loads on soil behavior. The findings underscore the importance of considering these factors in the design and management of infrastructure involving expansive soils. The research demonstrates that fissures exacerbate soil deformation and that both irrigation and loading conditions play critical roles in shaping soil behavior. These insights are crucial for developing effective strategies to address the challenges posed by expansive soils, including soil stabilization and moisture control measures. As infrastructure projects increasingly encounter expansive soils, understanding their behavior through model testing will continue to be valuable. By integrating these insights into design and mitigation practices, engineers and planners can improve the stability and performance of structures built on or with expansive soils, ultimately contributing to more resilient and sustainable construction practices.

Acknowledgement

None.

Conflict of Interest

The authors declare that there is no conflict of interest.

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