Investigation of Foundation Movement Claims

Foundation systems support various loads from above in the structure, including the weight of materials, occupancy, and environmental factors – such as water, wind, and seismic activity. The stability of a structure may rely on the adequacy of its foundation, which can be classified into shallow or deep foundations. Soil behavior is another critical factor influencing structural stability. Different soil types can affect the longevity and safety of buildings, making it essential for industry professionals to understand and address these variables. 

This blog explores the impact of various soil types on structures and offers strategies to identify and mitigate these challenges effectively.

Shallow vs. Deep Foundations and Their Analysis Tools

Shallow foundations are ideal for residential, light industrial, and small commercial buildings, especially when soil conditions are favorable just below the surface. They are cost-effective and include types such as concrete spread footings, concrete slabs on grade, and retaining walls. 

In contrast, deep foundations may be needed for areas with poor soil conditions, including wet/coastal regions, steep slopes, or unstable soils. They are also needed for heavily loaded and/or deflection sensitive structures such as tall buildings or heavy industrial plants. These foundations utilize long elements that penetrate into the deeper soil/rock strata such as steel piles, concrete caissons, and drilled piers.

Depending on the level of complexity of the foundation configuration, investigating the cause of foundation movement may require various tools and techniques beyond a surface inspection to evaluate the role of the underlying soil and foundation conditions. Ground-penetrating radar (GPR) is frequently used to identify voids and anomalies beneath the surface. Electrical resistivity imaging can provide additional soil property data. 

For a more detailed analysis, soil borings utilizing hand augers and truck-mounted drill rigs can collect soil samples and test soil density. These investigations are crucial for pinpointing the causes of foundation movement and determining suitable remedial actions.

Foundation Challenges from Underlying Soils

Water significantly influences foundation movement by destabilizing soil. Rainwater, irrigation, gutter discharges, and leaks from water or sewer lines can all impact foundations. Certain soils, such as collapsible, loose fill, and those containing peat or organics, become problematic when saturated, causing structures to settle.

Collapsible soils are a primary concern due to their tendency to compact and settle when exposed to moisture, which can lead to structural issues over time. Common in desert environments, these soils can cause pipes and other underground structures to bend and leak. For example, in the southwestern United States, periodic rains compact the soil, leading to leaks inside buildings. Understanding collapsible soils is crucial for developing effective mitigation strategies.

Organic soils also pose challenges, containing high percentages of organic material that decompose and lose mass over time, causing overlying soils to settle. These soils often include woody materials like roots and tree stumps, leading to secondary settlement over extended periods. Structures built on soils with more than 5% organic content can experience significant settlement issues, necessitating long-term monitoring and remediation.

Buried debris within soil, such as bricks, drywall, and concrete from construction, can cause uneven settlement and cracks in buildings. For instance, buried debris within and below fill soils due to improper site preparation can be a cause of significant settlement in overly structures. Identifying and addressing buried debris is essential for structural stability and preventing long-term damage.

Shrink-swell clays, which expand and contract with moisture changes, are another major concern, causing extensive damage to buildings and infrastructure. The American Society of Civil Engineers estimates that one in four US residents experience damage from these clays, with annual damages exceeding $15 billion. 

Shrink-swell clays can be found in certain areas throughout the United States, with regions like Texas and the Dakotas being particularly affected due to the high shrink-swell potential of the clays in these areas. Tools like the USDA Websoil Survey, along with site-specific testing, can help identify areas with shrink-swell clays and guide construction practices to mitigate their impact.

Importance of Soil Assessment and Remediation

Understanding the causes and implications of foundation movement is crucial for professionals in the construction, engineering, and insurance industries. Proper investigation and assessment of soil conditions and foundation systems can be helpful to ensure the stability and longevity of structures. 

By using appropriate tools and techniques, professionals can identify the causes of foundation movement and implement effective remedial actions to prevent further damage. Addressing foundation movement issues promptly can help maintain the integrity of buildings and structures, ensuring their functionality for years to come.

Understanding soil behavior and its impact on structures is essential for construction, property development, and insurance professionals. Collapsible soils, organic soils, buried debris, and shrink-swell clays all present unique challenges that require careful monitoring and remediation. 

By utilizing tools and investigation techniques to identify and address these issues, professionals can ensure the stability and longevity of structures, ultimately reducing risks and preventing costly damages.

Final Thoughts: Ensuring Structural Integrity

A comprehensive grasp of foundation movement and soil behavior is critical for professionals in construction, engineering, property development, and insurance sectors. Effective investigation and assessment of soil conditions and foundation systems are paramount to ensuring structural stability and longevity. 

Identifying and addressing specific challenges posed by various soil types, such as collapsible soils and shrink-swell clays, can mitigate risks and prevent costly damage. Prompt and appropriate remedial actions will safeguard the integrity, safety, and functionality of buildings and structures.

Partner with Envista Forensics

At Envista Forensics, we understand the critical role that soil behavior and foundation performance play in construction integrity and loss investigations. Our team of experienced forensic engineers, geotechnical experts, and construction consultants provides comprehensive assessments to identify root causes, mitigate risks, and support informed decision-making.

Whether you're dealing with foundation movement, water-influenced soil issues, or structural concerns, Envista delivers the technical expertise and clear reporting needed to resolve complex cases.

Contact us today to learn how Envista Forensics can support your next project or investigation with precision, insight, and confidence.