Alkali-Aggregate Reaction in Concrete Dams

Alkali–aggregate reaction (AAR) is one of the most consequential long-term degradation mechanisms affecting concrete dams. Its slow and spatially variable expansion can alter internal stresses, promote cracking and joint movement, and produce progressive deformations that affect serviceability, operability, and structural safety. Because these effects may overlap with those caused by temperature, loading, restraint, and other deterioration processes, a credible appraisal requires the careful integration of material evidence, field observations, monitoring data, and structural analysis. This book presents an integrated framework for diagnosing, quantifying, and modeling AAR in dam systems. It connects dam-scale manifestations, instrumentation records, core testing, and nondestructive evaluation to analysis-ready parameters and modeling assumptions. Organized as a step-by-step appraisal pathway, the book progresses from mechanism discrimination and damage characterization to potential failure modes, finite element simulation, model calibration and validation, uncertainty quantification, risk-informed evaluation, and long-term prognosis. It also addresses compound hazards, mitigation and rehabilitation strategies, documented dam case histories, and emerging applications of artificial intelligence and advanced monitoring technologies. Written for structural engineers, dam-safety professionals, consultants, owners, and regulators, the book provides practical guidance without requiring deep specialization in cement chemistry or experimental method development. It is also suitable for graduate students and researchers seeking a rigorous yet application-focused introduction to AAR-affected dams. By combining theoretical foundations with practical workflows, the book supports more transparent decisions concerning monitoring, analysis, intervention, and the long-term management of aging concrete dams.