Numerical Modelling of CFS Three-Story Strap-Braced Building under Shaking-Table Excitations.

Alessia Campiche

doi:10.3390/ma14010118

Abstract

In recent research activities, shake-table tests were revealed to be useful to investigate the seismic behavior of cold-formed steel (CFS) buildings. However, testing full-scale buildings or reduced-scale prototypes is not always possible; indeed, predicting tools and numerical models could help designers to evaluate earthquake response. For this reason, numerical modelling of two strap-braced prototype buildings, recently tested on shake-table at University of Naples Federico II in cooperation with Lamieredil S.p.A. company, was developed. The models were validated trough the comparison between experimental and numerical results, in term of dynamic properties (fundamental period of vibration and modal shapes), peak roof drift ratios and peak inter-story drift ratios. Although dynamic properties of mock-ups were captured with accuracy by the developed models, the comparison highlighted the need to consider accumulation of damage and rocking phenomenon in the modelling to capture with good accuracy the seismic behavior of CFS strap-braced building, subjected to high intensity records.

Highlights

Seismic behavior of structures has been a key topic in the last decades and still under investigation
The University of Naples “Federico II” carried out research devoted to the evaluation of dynamic properties and seismic response of both traditional steel structures [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21] and lightweight steel systems [22,23,24,25,26]
In the state of the art only the main lateral force resisting system (LFRS), i.e., strap-braced wall, is considered and two modelling approaches are employed: (i) A simplified approach in which the nonlinear behavior of steel straps is represented by a spring or a truss element [27,28,29,30]; (ii) detailed FE model using shell or frame elements [31,32,33,34] concerning different geometrical and material details

Summary

Introduction

Seismic behavior of structures has been a key topic in the last decades and still under investigation. The University of Naples “Federico II” carried out research devoted to the evaluation of dynamic properties and seismic response of both traditional steel structures [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21] and lightweight steel systems [22,23,24,25,26] After a brief introduction of mock-up geometries and shake-table tests, the paper provides the description of numerical modelling of the two tested mock-ups and the validation through the comparison with experimental results

Mock-Up Description

Shake-Table Tests

Numerical Modelling

Findings

Conclusions