This session, sponsored by ACI Committee 236, will explore a diverse range of advanced analytical and characterization techniques for concrete and cementitious materials. Invited experts will discuss advanced methods for measuring chemical and physical composition, including but not limited to diffraction, microscopic imaging, petrography, and spectroscopy. In addition, experts will cover mechanical characterization, thermal and calorimetric analysis, rheological properties, and advanced non-destructive testing methods. Attendees will gain insights into fundamentals, practical applications, and the benefits and limitations of various techniques that contribute to enhanced concrete resilience, durability, sustainability, and overall performance. This session is suitable for researchers, engineers, and practitioners interested in expanding their toolkit of analytical methods for concrete materials.
Learning Objectives:
(1) Understand the broad categories and fundamental principles of advanced analytical techniques relevant to concrete and cementitious materials;
(2) Learn how to effectively select appropriate characterization and analysis methods based on specific material properties, structural applications, and research objectives;
(3) Gain practical knowledge regarding the implementation, interpretation of results, common challenges, and best practices for advanced concrete characterization methods;
(4) Explore recent innovations, case studies, and future directions for advanced analytical techniques aimed at improving concrete material quality, durability, and structural integrity.
XRD in Cement Science: From Bragg Peaks to Time-Evolving Reactions
Presented By: Franco Zunino
Affiliation: UC Berkeley
Description: The widespread adoption of X-ray diffraction (XRD) as a cornerstone analytical technique in both academic and industrial laboratories has revolutionized the field of cement science. It is now routine to determine the phase assemblage of various cementitious composites, and in many cases, quantitative phase analysis is achieved through Rietveld refinement. The broad use of these methods is largely driven by advances in software that enable near-complete automation of refinement routines for well-characterized systems. Typically, Bragg–Brentano (reflection) geometry is preferred, with copper remaining the most common X-ray source used in cement laboratories. In recent years, growing interest has emerged in time-resolved (in situ) XRD measurements, with various experimental setups developed to overcome the challenges of monitoring hydration and reaction kinetics within the instrument. Transmission geometry has gained attention as a promising alternative, particularly due to the advantages of capillary configurations for controlling parameters such as temperature. From an analytical perspective, the increasing use of novel supplementary cementitious materials (SCMs) containing glassy or amorphous fractions of diverse compositions has further complicated quantitative analysis. This complexity has driven the development of new data interpretation approaches, such as the Partial Or No Known Crystal Structure (PONKCS) method, to address the challenges of modern cement XRD quantification.
XRF and Micro-XRF
Presented By: Amir Behravan
Affiliation: Virginia Transportation Research Council
Description: X-ray fluorescence (XRF) and micro-XRF are powerful analytical techniques for qualitative and quantitative elemental characterization of cementitious materials. This presentation provides a comprehensive overview of the underlying physical principles, instrumental configurations, and analytical capabilities of both methods. The discussion covers the excitation and detection processes of characteristic X-rays, calibration and quantification procedures, and the influence of matrix effects on measurement accuracy. The advantages of micro-XRF over conventional XRF, particularly in terms of spatial resolution and elemental mapping, are emphasized. Attention is also given to limitations such as detection thresholds, surface irregularities, and sample preparation challenges that affect data reliability. The session aims to enhance understanding of how XRF-based methods can be effectively applied in research and forensic evaluation of concrete materials to determine elemental composition, assess chemical heterogeneity, and support phase identification. Selected examples are presented to demonstrate the practical applications of these techniques in characterizing various concrete systems.
Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy (SEM/EDS)
Presented By: April Snyder
Affiliation: ECS Mid-Atlantic
Description: Scanning electron microscopy is a powerful tool for investigation of cementitious materials and has become invaluable for characterization of chemical interactions, and correlation between performance and microstructural characteristics. This presentation will provide a comprehensive overview of various applications of SEM/EDS techniques for cement and concrete evaluations. The use of SEM/EDS for hardened concrete forensic failure investigations, typical chemical deterioration mechanisms (ASR, DEF) and microstructural characterization including water-cementitious ratio estimation and cement and SCM hydration will be discussed with project examples. The application of automated particle analyses of blended cements and cementitious products for particle size and characterization will also be presented.
Raman Imaging
Presented By: Krishna Chaitanya Polavaram
Affiliation: Turner-Fairbank Highway Research Center - FHWA - G
Description: Raman imaging provides spatial maps of molecular vibrations with high chemical specificity, enabling identification of mineral phases, hydration products, and degradation signatures in cementitious materials. This talk presents Raman-based multimodal characterization for cement and concrete, including practical sample preparation (polished sections and surface finishing) and data analysis workflows (preprocessing, feature extraction, and basic chemometrics). We also cover instrumentation and data fusion strategies, with emphasis on robust, reproducible workflows suitable for research settings. As a concrete example from our work, we outline DISCO (Dual-Input Spectral COrrelation)—a Raman-centered framework that fuses Raman with EDS to illustrate how multimodal data can yield cross-modal insights, while remaining broadly applicable to multimodal cement research. The talk will highlight general principles and latest advances, then touch on how such approaches can be adapted to your own work.
Thermal Analysis Methods (TGA/DSC)
Presented By: Aditya Kumar
Affiliation: Missouri University of Science and Technology
Description: Thermal analysis methods—particularly thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC)—offer powerful means to probe the chemical composition, thermal stability, phase transformations, and reaction mechanisms of materials. This presentation will focus on how TGA/DSC can be effectively used to characterize a wide range of materials, including cementitious systems such as cements, supplementary cementitious materials (SCMs), and hydrated pastes. Emphasis will be placed on best practices for sample preparation—ensuring minimal chemical/structural changes prior to testing—and on practical considerations for instrument operation, calibration, and data interpretation. The talk will also outline strategies for analyzing complex TGA/DSC data, such as deconvoluting overlapping thermal events and correlating mass loss (from TGA) with enthalpic signatures (from DSC). Finally, specific case studies will be presented to demonstrate how TGA/DSC, when combined with complementary characterization techniques, can elucidate the thermal activation–induced changes in the structural and chemical composition of clays.
Calorimetry
Presented By: Sivakumar Ramanathan
Affiliation: University of Miami
Description: This presentation will highlight the applications of isothermal and semi-adiabatic calorimetry in studying cementitious materials. Isothermal calorimetry is typically conducted on small quantities of cementitious paste mixtures, whereas semi-adiabatic calorimetry is utilized for larger mortar and concrete samples. As a versatile analytical technique, isothermal calorimetry enables accurate evaluation of early age properties of cementitious systems and reactivity of supplementary cementitious materials (SCMs). In cementitious systems, isothermal calorimetry is used to obtain insights into reaction kinetics, early age degree of hydration, and sulfate balance considerations in OPC and blended cementitious mixtures. The effect of temperature, water-to-cementitious materials (w/cm) ratio, chemical admixtures, and different SCM dosages can be assessed using the calorimetry and correlated to early age compressive strength of these mixtures. Beyond conventional cementitious systems, hydration kinetics of alternative cementitious systems such as calcium sulfoaluminate cements and alkali activated cementitious systems can also be evaluated using these techniques. The talk will also address the role of isothermal calorimetry in evaluating SCM reactivity through the R3 and modified R3 tests. Evaluation of SCM reaction kinetics from isothermal calorimetry and its correlation to later age cementitious paste and mortar properties will be addressed. Correlations between isothermal and semi-adiabatic calorimetry data will be presented. The correlation between temperature increase and long-term durability will be discussed in this presentation. Case studies and data interpretation considerations will be discussed to demonstrate the utility and versatility of calorimetry.