Expanded Clay Aggregate in Engineering: Crushing Behaviour and Design Implications offers the first comprehensive, multi-scale analysis of crushing in expanded clay aggregate (ECA), a widely used but poorly understood engineered material. The book challenges conventional assumptions that have long guided the design and application of ECA and presents a rigorous, mechanistic understanding of how this manufactured material responds to stress. Through a systematic exploration of crushing initiation, propagation, and size-dependent effects, the book reveals how ECA's distinctive cellular structure produces behaviour fundamentally different from that of traditional geomaterials. Positioned at the intersection of granular mechanics, geotechnical engineering, and materials science, the book is an essential read for researchers and graduate students working on crushable materials, as well as practitioners seeking reliable, performance-based design approaches for lightweight aggregates. Both scientifically rigorous and practically oriented, Expanded Clay Aggregate in Engineering establishes a new foundation for predicting, controlling, and optimising the behaviour of expanded clay aggregate in modern engineering applications.