BEYER, KATRIN1; TONDELLI, MARCO2; PETRY, SARAH3, PELOSO, SIMONE4

1) Assistant Professor, Earthquake Engineering and Structural Dynamics Laboratory (EESD), School of Architecture, Civil and

Environmental Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL), Switzerland, katrin.beyer@epfl.ch

2) Scientific Assistant, Earthquake Engineering and Structural Dynamics Laboratory (EESD), School of Architecture, Civil and Environmental

Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL), Switzerland, marco.tondelli@epfl.ch

3) PhD student, Earthquake Engineering and Structural Dynamics Laboratory (EESD), School of Architecture, Civil and Environmental

Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL), Switzerland, sarah.petry@epfl.ch

4) Researcher, EUCENTRE – European Centre for Training and Research in Earthquake Engineering, Pavia, Italy. E-mail:

simone.peloso@eucentre.it

 

In Switzerland many new residential buildings are designed as mixed structures with unreinforced masonry (URM) walls and reinforced concrete (RC) walls while existing URM structures are often retrofitted by replacing selected URM walls by RC walls. The lateral bracing system of the resulting structure consists therefore of URM walls and some RC walls. All walls are coupled by RC slabs and/or masonry spandrels. Since the seismic performance of such mixed structures– despite being very common in design and retrofit– is still not well understood, a shake-table test on a four-storey RC-URM wall structure was performed at the TREES laboratory of the EUCENTRE in Pavia (Italy). In this paper we present the details of the shake-table test and discuss its results. We compare the observed behaviour to that generally observed for URM structures and conclude on the effect of adding slender RC walls to URM buildings in terms of damage evolution. The force-displacement response of the structure is presented, its response for the two loading directions discussed and different methods for computing the base shear force compared.

 

Keywords: Shake-table test, mixed structure, unreinforced masonry wall, reinforced concrete wall, seismic behaviour.