Bridging scales from atomistic to macro - a demonstration from steel corrosion in concrete

Speaker: Prof. Burkan Isgor, Oregon State University, United States

Hosts: Dr Prannoy Suraneni, University of Miami, United States and Prof. Karen Scrivener, EPFL, Switzerland

Title: Bridging scales from atomistic to macro through the synergistic use of computational and experimental methods ― a demonstration from steel corrosion in concrete

Civil engineering structures are large – really large. A simple structure would contain many tons of steel and concrete to provide the functions that it is designed to deliver. Our structures serve for many decades while resisting extreme loads. We expect over 100 years of service life from them even in the most challenging environments. In this large scale of dimension and time span, when we look at these structures, we don’t see atoms or molecules ― we see beams, columns, or walls. We don’t consider processes that take place in nano-seconds ― we measure time in years. Despite this reality, many processes that affect the properties of these structures are governed by processes that occur in atomistic scale and time frames that are substantially smaller than years. Therefore, understanding how civil engineering structures respond to mechanical or environmental loads, and how they age over the years, requires bridging the length and time scales from atomistic to structural level. However, this is not a trivial task as our methods are typically designed to operate at well-defined ranges of scales. When a method fails to provide useful information at a given scale, another method takes over. When experiments become impossible, we turn to computational methods. Typically, the expertise of individual researchers also remains within the scale range of the methods they use. Therefore, bridging scales requires trans-disciplinary collaboration. In this talk, I will present a demonstration of the process of bridging scales from atomistic to macro through the synergistic use of computational and experimental methods. The focus of the demonstration will be steel corrosion in concrete, a very well-described civil engineering problem. We will identify reinforcement corrosion related questions we observe at structural level and seek their answers in lower dimensions ― all the way down to atomistic scale. It will be shown that the answers, or perhaps more unassumingly, the attempts to answering some of the big questions come from trans-disciplinary collaboration of people who look at problems in different scales.

ABOUT RILEM:

The mission of RILEM is to advance scientific knowledge related to construction materials, systems and structures and to encourage transfer and application of this knowledge world-wide.

This mission is achieved through collaboration of leading experts in construction practice and science including academics, researchers, testing laboratories and authorities.