C. R. Calladine 
Plasticity for Engineers [PDF ebook] 
Theory and Applications

This book focuses on the plastic property of materials, and the way in which structures made of such material behave under load. It is intended for civil, mechanical, electro-mechanical, marine, and aeronautical engineers for under-graduate or post-graduate courses or research, and professionals in industry. Professor Calladine, from long experience in teaching, research and industry, here delivers a readable and authoritative account of theory and applications. He presents the classical "perfect plasticity material" as a model of irreversible mechanical behaviour, using this perfect plasticity property to analyse a range of continuum structural problems and metal-forming processes relevant to engineering practice.