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Past lateral cyclic or seismic tests of concrete frames with smooth bars in columns are very few and limited as far as the test structure's size and geometry are concerned; moreover, they have not focused on the effect of detailing and lap-splicing of such bars on local and global behaviour. To help fill this knowledge gap with new data, the paper presents the cyclic lateral load test of a 2:3-scale three-storey, one-by-two-bay, strong beam-weak column RC frame, focusing on the effects of the column's smooth bars and of their detailing on local and global behaviour. Slippage of bars caused concentration of column deformations in flexural cracks at the top and base sections and gave to the global hysteresis loops a shape typical of bond-slip behaviour, but without cyclic strength decay. Despite chord rotation demands of up to 0.055 rads and storey drifts of almost 5%, damage was limited and had nothing to do with the use of smooth bars in the columns. Despite the important role of bar slippage for the response, bar strains show that wherever the surrounding concrete was in compression, column bars were in compression as well. Lap splices at and/or FRP wrapping of column end regions did not have systematic effects on column behaviour. Overall, no adverse effect of the use of smooth bars was identified. [ABSTRACT FROM AUTHOR]

Substructured Pseudodynamic testing is used to study the transverse seismic response of a bridge with box-girder deck monolithically connected to circular piers, but free to move laterally at the abutments. The tests are of two types, each one with two variants: with the pier footing rocking on elastic soil and uplifting from it, or fixed to rigid ground. The first type concerns a two-span deck connected monolithically to a central pier and supported at each end on the abutment through a pair of elastomeric bearings, which are stiff and strong in compression but very soft and weak in tension. The second one concerns the interior piers of multi-span bridges having all spans equal and all piers similar. The pier was physically tested at 1:2 scale; everything else was numerically simulated online with Opensees. The deck, the soil and the bearings were modeled as elastic, but not allowing tension to develop at the soil-footing interface, and the bearings two orders of magnitude more flexible in tension than in compression. In the first type of tests, at a peak ground acceleration (PGA) of 0.15 g, the footing uplifted, the bearings developed tension, but the pier stayed elastic. In the second type of tests, with a PGA of 0.4 g, uplifting of the footing did not prevent plastic hinging at the pier base, but reduced significantly the pier damage. A cyclic quasi-static test in the end shows the deformation capacity margins of the pier. [ABSTRACT FROM AUTHOR]