Nanotechnologies for concrete and composed structures for seismic safety

Abstract

Performance requirements of civil structures are becoming more and more severe in recent years. Users pay an increasing attention to safety and functionality of systems and components over time, because of the impact of failure and/or down time from the social and economic point of view. The market globalization and the transfer of technologies among different branches of engineering and mate− rial science are also influencing the concept of safety of civil structures – buildings, bridges and other critical infrastructures. A differ− ent paradigm in the field of building and infrastructure technology has been envisaged and investigated. In particular, issues like degra− dation control and assessment of materials and components in order to enhance durability of structures and overall performances of the constructions are focused; moreover, emergency management, structural safety and performance monitoring of structures exposed to nat− ural risks such as earthquakes are targets of recent researches. The industry of the constructions must face problems related to the main− tenance of structural elements in concrete or to mixed structure. In virtue of such problem list in the last years it has also spread the use of concretes to high technology with particular characteristics of seismic resistance. The use of this concrete allows to overcome the con− nected difficulties with the geometric complexity of the structures and the problems originated from sections to tall percentage of ar− mor. The addition, then, of fibers of reinforcement in partial or total substitution of the traditional metallic armor it allows to get best performances both static that dynamics of existing structures.