Ultra‐high‐performance Concrete

This chapter focuses on the ultra-high-performance concrete (UHPC), including its definition, material composition, design methods, physical and mechanical properties, volumetric stability, and durability. It discusses the workability, hydration behavior, pore structure, and hydration products of UHPC, as well as its compressive strength, tensile properties, and micro/nano-mechanical properties. The chapter also explores the shrinkage characteristics and mechanisms of UHPC, and the effects of steel fibers and internal curing on its shrinkage performance. Additionally, it presents the durability of UHPC in terms of freeze–thaw resistance, sulfate attack resistance, and chloride ion penetration resistance. The chapter introduces novel UHPCs, such as green UHPC incorporating steel slag and lightweight UHPC using high-strength lightweight aggregates. Finally, it showcases the application of UHPC in municipal solid waste pre-treatment plants and steel bridge deck pavements.