T. KVANDE1, K.V. HØISETH2, A.T. VERMELTFOORT3 and R. VAN DER PLUIJM4 1Norwegian Building Research Institute, 2Norwegian University of Science and Technology 3Technische Universiteit Eindhoven, 4TNO Building and Construction Research

Knowledge of masonry deformation caused by creep and shrinkage is important when designing for crack resistance. The main purpose of the investigation presented was to study the creep behaviour of typical Norwegian masonry made of light expanded clay aggregate (LECA) concrete blocks. Normally such masonry is built without mortar in the perpend joints. When the masonry is exposed to restrained shrinkage, an unpredictable tensile stress distribution may occur because of the free (open) joint. Instead of using creep tests under compression, specimens were loaded with constant uni-axial tensile stress in the longitudinal direction of the masonry. The ESPI measurements showed a relatively large opening of the free perpend joint, which was due to the stress distribution in the specimen. The creep coefficient obtained was especially large for the highest stress levels. The experimental study is presented in detail in [1].