The 78m Arts Tower at the University of Sheffield was refurbished during the period 2009 to 2011, with improvements that included replacement of facades and partitions. The structural changes were reflected in changes in dynamic properties that were tracked by a combination of long-term acceleration monitoring and vibration tests to identify local and global vibration modes.The global horizontal plane modes of the building were correlated with finite element model simulations and real-time automated operational modal analysis to characterize the effects of the structural changes on horizontal vibration modes in sway and torsion. Also, floor vibration tests linked to the finite element simulations identified the contribution of 'non-structural partitions' on the floor dynamic performance.Replacement of heavy masonry partitions with modern lightweight forms has resulted in reduction of stiffness, yet there is no obvious change in sway vibration serviceability and floor performance remains satisfactory. KeywordsBuilding vibration monitoring retrofit floor sway partition 2 University of Sheffield Arts Tower history, structural details and upgradeThe University of Sheffield Arts Tower has the distinction of being the tallest university building in the UK and until 2009 was the tallest building in Sheffield. The building was completed in 1965 and is now a Grade II listed property, in recognition of its heritage status and imposing strict requirements on structural alterations including a retrofit that was completed in 2011.The building (Figure 1) has 21 storeys above ground floor (level 0), 2 basement levels, and is approximately 80m high, 36m wide and 20m deep. The basement houses lecture theatres and plant rooms which extend outside of the tower footprint and level 1 is 8.54m above level 0, with a mezzanine level. Normal floors are spaced at 3.55m intervals and as built were sub-divided by non-load bearing 75mm thick 'breezeblock' masonry partitionsThe structural frame comprises 250mm reinforced concrete (RC) flat slabs spanning between two closely spaced RC cores and RC columns arranged around the perimeter of the floors (Figure 2).There are two frame arrangements; below level 1 there are 16 perimeter rectangular columns of 965mm by 965mm, with a transfer slab to the 94 rectangular upper columns of 203mm by 406mm at 1.8m centres in the long direction and 1.12m in the short direction.Structural lateral stability is principally provided by the two reinforced concrete shear cores acting as vertical cantilevers. Lateral load is transmitted to the cores through the building cladding into the edge of each floor and then transferred by membrane plate action to the core walls. The cores are offset with regard to the floor plate long axis dividing floors into narrow and wide sides. Because of the structural eccentricity, the building's response under lateral loads involves both lateral and rotational displacement.Shortly after the Arts Tower was first occupied in 1966 a number of occupants reported perceiving moveme...

Abstract. In this paper the hysteretic behaviour of elastomeric dampers and their effect on steel moment resisting frames was evaluated. A new constitutive model was proposed, based on the Generalized Maxwell Model (GMM), which was able to capture the characteristics of the dampers under dynamic loading in a range of frequencies and amplitudes. This model was incorporated into the Finite Element (FE) Software OpenSees [1], and was used to validate the dampers behaviour. A simple steel moment resisting frame was modelled, and analytically tested under under strong ground motions, scaled according to Eurocode 8 [2] response spectrum. Both analytical and experimental results show the efficiency and the effectiveness of the elastomeric dampers with regard to structural response.

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