Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Heresies on shrinkage and creep mechanisms
First of all it is outlined that shrinkage as measured on drying concrete is not a simple material property but the complex response of a given specimen to lang lasting time-dependent internal stresses. Then the physical basis of two frequently cited approaches to explain the origin of hygral shrinkage is briefly described: capillary action and disjoining pressure. The predictions of the two concepts are compared with experimental findings. The following examples have been selected for a critical comparison: (1) direct observation of the interaction of water in a narrow gap, (2) sorption and length change isotherms of different materials, (3) capillary shrinkage of fresh and young concrete, (4) shrinkage of water repellent concrete, and (5) influence of ion concentration on shrinkage. From the presented results it can be concluded that capillary action plays a minor role in the process of shrinkage of cement-based materials.
Heresies on shrinkage and creep mechanisms
First of all it is outlined that shrinkage as measured on drying concrete is not a simple material property but the complex response of a given specimen to lang lasting time-dependent internal stresses. Then the physical basis of two frequently cited approaches to explain the origin of hygral shrinkage is briefly described: capillary action and disjoining pressure. The predictions of the two concepts are compared with experimental findings. The following examples have been selected for a critical comparison: (1) direct observation of the interaction of water in a narrow gap, (2) sorption and length change isotherms of different materials, (3) capillary shrinkage of fresh and young concrete, (4) shrinkage of water repellent concrete, and (5) influence of ion concentration on shrinkage. From the presented results it can be concluded that capillary action plays a minor role in the process of shrinkage of cement-based materials.
Heresies on shrinkage and creep mechanisms
Irrtümer über Schwindung und Kriechmechanismen
Wittmann, F.H. (Autor:in)
2009
7 Seiten, 11 Bilder, 30 Quellen
Aufsatz (Konferenz)
Englisch
Micromechanical analysis of creep and shrinkage mechanisms
| British Library Conference Proceedings | 2001
| British Library Online Contents | 1993
| Online Contents | 1993
Creep and shrinkage of concrete
| Engineering Index Backfile | 1969
| Springer Verlag | 2014