Sessions & Events

Forensic Investigations of Concrete Failures Using Advanced Techniques, Part 2 of 2

Monday, October 27, 2025  11:00 AM - 1:00 PM, H - Holiday 3

This session will provide attendees with a comprehensive understanding of how advanced material characterization techniques, commonly used in academic research, can be effectively applied to real-world forensic investigations of concrete failures. The focus will be on identifying the root causes of issues in both new construction and existing concrete structures. Presentations will highlight how these techniques can uncover underlying problems; help mitigate risks and improve the long-term durability of concrete. Participants will gain valuable insights into how material science tools can diagnose concrete issues, provide actionable solutions, and ultimately prevent failure. This session is designed for professionals across multiple disciplines, including consultants, contractors, engineers, researchers & material scientists. In general, anyone involved in the design, construction, and maintenance of concrete structures will benefit from attending.

Learning Objectives:
(1) Interpret forensic investigation data to make informed decisions about root causes and appropriate remedial actions in concrete structures;
(2) Compare and evaluate case studies of concrete failures to identify recurring patterns, contributing factors, and lessons learned;
(3) Develop action plans for implementing durability-focused practices in concrete design, construction, and maintenance based on forensic evidence and field data;
(4) Explain the role of interdisciplinary collaboration—including engineers, contractors, and materials specialists—in resolving complex concrete performance issues and preventing future failures.

This session has been approved by AIA and ICC for 2 PDHs (0.2 CEUs). Please note: You must attend the live session for the entire duration to receive credit. On-demand sessions do not qualify for PDH/CEU credit.

Petrographic Techniques to Identify and Determine Relative Abundance of Iron Sulfide Minerals in Concrete Aggregate

Presented By: April Snyder
Affiliation: ECS Mid-Atlantic
Description: Identification of iron-sulfide minerals in concrete aggregate is becoming increasingly important in light of cases of deterioration of residential concrete foundations and its financial implications on homeowners. Recent legislation in the Northeast US is establishing limits for sulfur in concrete aggregate with specific concerns on pyrrhotite content. This presentation will provide an overview of a petrographic method to identify and quantify the iron-sulfide content in aggregate using petrographic techniques including reflective light microscopy and scanning electron microscopy with energy dispersive spectroscopy (SEM/EDS) x-ray mapping.

Application of Advanced X-ray and Neutron Imaging Techniques in Concrete Materials

Presented By: Mehdi Khanzadeh Moradllo
Affiliation: Temple University
Description: The durability of concrete in different environments is still a topic of continuing interest due to its scientific complexity and economic impact. This presentation discusses the important role of advanced X-ray and Neutron imaging techniques in a deeper understanding of the deterioration mechanisms in concrete materials at a microstructural level. Additionally, it highlights how the micro-scale study of concrete materials enables us to manipulate and tailor the microstructure of materials. This opens up tremendous opportunities in developing high-performance and novel concrete materials.

A Microscale Assessment of a Pyrrhotite-Impacted Basement

Presented By: Michael Mengason
Affiliation:
Description: Residential foundations in areas of southern New England have failed due to the mineral pyrrhotite (Fe1-x S, where x = 0 to 0.125) in aggregate used in their construction. The aggregate was sourced from a thin band of Brimfield Schist trending northeast from Connecticut into Massachusetts. Pyrrhotite exposed to air and water undergoes oxidation to form iron oxyhydroxides and release hydrogen and sulfate ions. These ions interact with the cement paste, consuming a portion of the matrix to produce new volumetrically larger phases (e.g., ettringite). This internal sulfate attack leads to extensive cracking of the concrete and a loss of structural integrity requiring costly replacement. To better understand the changes taking place during this process, cores removed from a residential home in Connecticut with different degrees of fracturing were prepared for imaging and microanalysis. The fracture system was documented using UV epoxy impregnation and SEM imaging. Data were collected on the extent of pyrrhotite oxidation (evident in all cores regardless of fracturing) and the composition of the cement paste by SEM using BSE (Backscatter Electron) imaging and EDS (Energy Dispersive Spectrometry). Methods refined in this investigation will be applied to further homes to better define the degradation process.

Leveraging Ancillary Petrographic Methods to Better Understand Material Performance

Presented By: Jamison Langdon
Affiliation: Braun Intertec Corporation
Description: Modern petrographic evaluations often require analysis beyond the typical use of stereoscopy and polarized light microscopy to identify the contributing factors observed regarding field performance of cementitious-based materials. These ancillary methods may include analyses such as portable X-ray fluorescence, color spectrophotometry, Fourier Transform Infrared, Raman spectroscopy, as well as numerous other methods. Observations and results of these analyses can also be utilized to accelerate understanding of material conditions in the initial stages of the forensic evaluation that allow the petrographer to adapt the investigation in a rapid and timely manner. Several methods will be discussed via case studies to show how these ancillary methods have been used to better understand material performance.

Forensic Analysis of Deep Foundation Failures

Presented By: Babak Vafaei
Affiliation: Black & Veatch Corporation
Description: Deep foundation failures can lead to severe structural and economic consequences, necessitating thorough forensic investigations to identify underlying causes. This presentation explores the application of advanced techniques in diagnosing defects, assessing structural integrity, and determining failure mechanisms in existing foundations. Case studies will highlight critical issues such as soil-structure interaction challenges, concrete deterioration, and load-bearing deficiencies. By examining real-world failures, this presentation will demonstrate how forensic analysis can mitigate risks, enhance long-term durability, and inform preventive strategies for future projects.

Performance Evaluation of Silane in Concrete Bridge Decks Using Transmission X-ray Microscopy

Presented By: Amir Behravan
Affiliation: Virginia Transportation Research Council
Description: Corrosion of steel reinforcement in concrete is a widespread issue. Silane is commonly used as a surface treatment to limit moisture and chemical ingress, but its long-term effectiveness remains uncertain due to the lack of standardized testing. A state DOT requested an evaluation after failures in silane-treated structures. Transmission X-ray microscopy (TXM) and optical imaging were used to assess mass transport properties and silane thickness in field samples. Optical staining revealed an average silane thickness of 2.5 mm across 14 projects, while TXM analysis showed an 8.5-fold reduction in contaminant penetration at a 2 mm depth compared to untreated concrete. This study demonstrates silane’s effectiveness in reducing permeability and corrosion risk, offering valuable insights for DOTs in selecting protective treatments for concrete infrastructure.