Results of pseudo-static tests with cyclic horizontal load on cast in situ sandwich squat concrete walls

In recent years, the seismic behaviour of structural systems composed of squat concrete walls has been the object of a renovate interest. This paper presents the results obtained in a wide experimental campaign carried out as a joint effort between the University of Bologna and the Eucentre labs in Pavia. This effort was devoted at the assessment of the seismic performances of cellular structures composed cast in situ sandwich squat concrete walls. In order to obtain a full characterization of seismic behaviour (stiffness, strength, ductility, energy-dissipation) of such structures, a number of tests were performed upon two dimensional (3.0 m by 3.0 m) cast in situ sandwich squat concrete walls (with and without openings). In the experimental tests a number of horizontal in-plane loading cycles were imposed to the specimens, while the vertical load was kept constant. The results obtained have shown that the tested elements are characterized by: (i) absence of a real failure; (ii) high values of the maximum horizontal load applied to the structural systems (higher than the applied vertical load); (iii) residual bearing capacity w.r.t. the vertical loads, also when large lateral deformations were developed; (iv) a good degree of kinematic ductility.