Seismic shear and acceleration demands in multi-storey cross-laminated timber buildings

Abstract

A realistic estimation of seismic shear demands is essential for the design and assessment of multi-storey buildings and for ensuring the activation of ductile failure modes during strong ground-motion. Likewise, the evaluation of seismic floor accelerations is fundamental to the appraisal of damage to non-structural elements and building contents. Given the relative novelty of tall timber buildings and their increasing popularity, a rigorous evaluation of their shear and acceleration demands is all the more critical and timely. For this purpose, this paper investigates the scaling of seismic shear and acceleration demands in multistorey cross-laminated timber (CLT) buildings and its dependency on various structural properties. Special attention is given to the influence of the frequency content of the ground-motion. A set of 60 CLT buildings of varying heights representative of a wide range of structural configurations is subjected to a large dataset of 1656 real earthquake records. It is demonstrated that the mean period (T m) of the ground-motion together with salient structural parameters such as building aspect ratio (), design force reduction factor (q) and panel subdivision () influence strongly the variation of base shear, storey shears and acceleration demands. Besides, robust regression models are used to assess and quantify the distribution of force and acceleration demands on CLT buildings. Finally, practical expressions for the estimation of base shears, inter-storey shears and peak floor accelerations are o↵ered.

Performance-based seismic design and assessment of rocking timber buildings equipped with inerters

“…Moreover, previous analytical studies have demonstrated that higher vibration modes can be coupled with the rocking motion and excited by the forces generated during impact, regardless of the frequency of the excitation [26]. This behaviour has been experimentally observed in steel rocking structures [27], it has been predicted to occur also in rocking timber structures, albeit with lower amplitudes due to their typically softer set down [28] and was speculated to lie behind some of the large peak acceleration amplifications anticipated in multi-storey panellized timber buildings with rocking motion components [29]. Wiebe and Christopolous examined the alternative of using multiple rocking sections over the height of a base-rocking system, thus allowing the designer to control the higher mode amplification of moments above the base of the wall [25].…”

Acoustic Characteristics of Cross-Laminated Timber Systems

“…Since the 1990s, the University of Graz has been one of the first institutions to undertake numerous international CLT research activities. Further, more complete and elaborated studies were carried out in the 2000s, on dimensional stability and stiffness [35] and the adequate connections for a high dissipation capacity: Ceccotti et al proposed a simplified method for the determination of the seismic behavior factor "q" of timber buildings [26], that measures a relative energy loss per oscillation cycle; Sustersic et al investigated the seismic analysis of multi-story cross-laminated timber buildings [29]; Gavric et al proposed an extended experimental program on typical cross-laminated panels connections [36]; Demirci et al investigated the scaling of seismic shear and acceleration demands in multi-story cross-laminated timber buildings and its dependency on various structural properties [37]; Sustersic et al worked with the issue of seismic retrofit and thermal insulation improvement of existing buildings with CLT technology [38].…”

“…It is also possible to build multi-story buildings, making the construction system in CLT attractive from the economic point of view and from the environmental perspective thanks to a reduced exploitation of the soil [26,37,101,102].…”

“…The CLT panels result to be particularly suitable also for energy upgrading of existing older buildings if combined with an effective insulation [38]. It is also possible to build multi-story buildings, making the construction system in CLT attractive from the economic point of view and from the environmental perspective thanks to a reduced exploitation of the soil [26,37,101,102].…”

Seismic drift demands in multi‐storey cross‐laminated timber buildings

“…The same modelling strategy outlined in the previous section was adopted while the position, dimension, type, and number of connectors between adjacent walls and slabs were obtained from Dujic et al, and Rinaldin and Fragiacomo . Other dynamic properties of the building were also well predicted by the OpenSees model developed() including an 8% difference in natural periods and a close estimation of peak accelerations (eg, 2.61g against 2.52g at the top floor for the experimental and numerical model, respectively). Notably, despite the simplifications, a maximum total cumulative difference of just over 7% was observed, and a good match in the temporal evolution of energy dissipation was attained (Figure 6G).…”