Minutes of Workshop 8

Abstract

Professor Roy had prepared some questions to introduce her introductory lecture directed at examining the possibility of building structure in such a way that demolition, when necessary, can be accomplished with relative ease, whilst producing materials suitable for recycling. After a historical recapitulation drawn from Roman practice, she pointed to the possibility of replacing demolition by dismantling. Since this is not always feasible, there remained the problem of defining the properties of a binder to facilitate demolition coupled with the characteristics of concrete for best performance during lifetime. Could the matrix be modified and as such what are the disadvantages of cement as a binder? This pointed to examining ways to recover unhydrated cement from the mortar and the effects of relatively reactive components. Other binders such as sodium silicates could be investigated. Perhaps the size of aggregate could be of influence. Ensuing discussion should also deal with compensating phase changes and ways to optimize bond through study of zêta potential and surface conditions.