Understanding Structural Assessment in Engineering

As the world continues to rapidly evolve, the demands placed on our buildings and structures do so as well. Ensuring their safety and stability is of utmost importance, and this is where regular, periodic inspections come into play. Through the process of a structural assessment, home owners or building owners and managers can gain a comprehensive understanding of their structure’s stability, functionality, and/or longevity. Not only does this provide invaluable peace of mind, but it can also help to reduce the likelihood of catastrophic failure or collapse. In this article, we will explore the critical necessity of a structural assessment and its importance in promoting the safety and longevity of our built environment.

What is Structural Assessment?

A structural evaluation is a comprehensive examination that involves assessing the structural integrity and performance of a building or structure. This critical process allows engineers and stakeholders to identify potential issues, assess safety, and extend the useful life of structures. In essence, it involves determining the current state of a structure and forecasting its future performance. This is achieved by evaluating several factors, such as the structure’s material properties, design and construction methods, environmental conditions, and previous maintenance or repair work. The typical output of a structural assessment is a report that informs building owners or developers about the building’s condition with regards to its intended use.

What is a Structural Assessment Report?

A Structural Assessment Report is a critical document that evaluates the soundness and condition of a building or structure. Typically, a licensed structural engineer conducts the assessment to identify any potential safety hazards or structural deficiencies. This comprehensive evaluation includes a thorough examination of the building’s foundation, walls, roof, floors, and other structural elements. Additionally, the engineer reviews the building’s history, including any past renovations or modifications that may have affected its structural integrity.

Depending on the circumstances, a Structural Assessment Report may be a standalone document or integrated into a more extensive planning document like a Development Plan, Historic Structures Report, or Condition Assessment Report. The report outlines the findings in detail and makes recommendations for necessary repairs or modifications to ensure the building’s safety and structural stability. It is crucial to organize the report in a clear and understandable manner for the end-user, who may not be an expert in the subject matter.

Importance of Structural Assessment

A structural assessment is a crucial component of structure maintenance and management, helping to identify potential issues that could lead to reduced performance, failure, or even collapse. Evaluates the safety of structures and ensures they comply with building codes, regulations and standards. By identifying non-compliance issues, engineers can develop strategies to address them, avoiding penalties and legal liability. Structural assessment also helps identify potential risks associated with a structure, such as seismic activity, wind loads, or flooding. Its primary goal is to identify potential problems early on and develop strategies to address them. By doing so, the risk of structural failure and costly repairs is significantly reduced.

Types of Structural Assessment

There are several types of structural assessment methods that engineers can use to evaluate the condition and performance of structures. The following are the most commonly used methods:

Non-Destructive Testing (NDT) Methods

Non-destructive testing (NDT) methods are widely used in the field of engineering for assessing the structural integrity of various types of structures, including buildings, bridges, pipelines, aircraft, and other mechanical systems. These methods are valuable tools for identifying structural defects or anomalies that could compromise the safety, reliability, or performance of a structure.

Some of the most common NDT methods used in engineering are:

• Ultrasonic testing (UT). UT uses high-frequency sound waves to detect internal flaws or defects within a structure. The method involves directing a beam of sound waves through the structure and measuring the time it takes for the waves to bounce back to a receiver. By analyzing the data collected from the reflected waves, engineers can detect cracks, voids, and other defects that may be present in the structure.
• Magnetic Particle Inspection (MPI). MPI is a non-destructive testing method used to detect surface and near-surface defects in ferromagnetic materials, such as steel. The method involves applying a magnetic field to the material and then applying a magnetic particle solution to the surface. Any surface defects or anomalies in the material will cause the magnetic particles to accumulate in those areas, making them visible under black light.
• Radiography is another NDT method used in engineering for structural assessment. Radiography uses X-rays or gamma rays to create an image of the internal structure of a material. By analyzing the image, engineers can identify any internal flaws or defects in the structure.
• Thermal imaging is another NDT method that is gaining popularity in the field of engineering. The method involves using infrared cameras to detect differences in temperature in a structure. These differences can indicate the presence of defects or anomalies that may be invisible to the naked eye.

Destructive Testing Methods

Destructive testing refers to methods that involve removing a small portion of a structure to assess its properties. These techniques are typically used to determine the strength, durability, and ability of a structure to withstand different loads and stresses. However, due to their expensive and time-consuming nature, they are usually reserved for situations where an accurate assessment is necessary or safety is a major concern.

Some common destructive testing methods include:

• Sampling of the core, which consists of extracting a small section of material from the structure, generally in the shape of a cylinder or disc, to evaluate its composition, quality, and resistance. This method is often used to assess the integrity of concrete and masonry structures, as these materials can weaken over time due to weathering and use.
• Load testing. This method involves applying known loads to the structure to measure its load capacity and resistance to deformation. Engineers use this approach to assess the ability of a bridge or similar structure to withstand extreme loads, such as heavy traffic or severe weather conditions.
• Shear wall testing. This technique is used to evaluate the strength and load-bearing capacity of structural walls. It involves removing a section of the wall to assess its thickness, composition, and resistance to load.

Visual Inspection Methods

Visual inspection methods require engineers to meticulously scrutinize the surface of a structure in order to detect any discernible indications of damage or decay, such as cracks, corrosion, or deformation. Various forms of visual inspection techniques are available for engineers to utilize in evaluating the state of a structure:

One prevalent form of visual inspection is a close-up visual inspection, which entails scrutinizing the structure at close range to detect any observable evidence of damage. Although this technique may require a significant amount of time and effort, it is often crucial for identifying inconspicuous indications of harm that may not be apparent from a distance.

Another type of inspection is remote visual inspection, which employs cameras or other remote sensing equipment to examine the structure from a distance. This approach is frequently utilized when it is hazardous or impractical to physically access the structure, such as when examining the exterior of a high-rise building.

A third visual inspection method is borescope inspection, which employs a flexible tube equipped with a camera to scrutinize the interior of a structure, such as a pipeline or a concrete structure. This technique enables engineers to identify any signs of damage or deterioration within the structure’s internal components that may not be visible from the exterior.

When is Structural Assessment Needed?

Without proper structural evaluation, buildings and other structures could be at risk of collapse or failure, which could result in injury or even loss of life. Some situations that may require a structural assessment include:

• During the design and construction of new structures.
• When existing structures are being renovated or refurbished. (which may involve changes to the load-bearing capacity or intended use of the structure)
• When a building is being bought or sold.
• During routine maintenance to ensure that the structure remains in good condition and is safe to use.
• After damage or disasters, such as earthquakes, floods, or hurricanes.
• In cases of incidents that affect the structure, such as vehicle crashes or impacts from other objects.
• When a structure has experienced differential settlement, that is, when parts of a structure sink or shift more than others due to changes in the foundation or underlying soil. (This can happen in older buildings or areas with unstable soil, and if left unaddressed, it can compromise the building’s structural integrity.)

How to Know If Your Building Needs a Structural Assessment

Deciding whether your building requires a structural assessment can be challenging. Nevertheless, the most dependable approach to determine this is by seeking the guidance of a reputable professional engineering company. At Eastern Engineering Group, our team of expert engineers, licensed as Special Inspectors, possess the necessary skills to comprehensively evaluate and address your structural needs. It’s important to keep in mind that a thorough structural assessment can significantly impact the durability and safety of your building, and most importantly, keep the tenants safe. Contact us today to get a free quote!

©️ 2023 Eastern Engineering Group wrote and published this article. All rights reserved.