Elsevier

Engineering Structures

Volume 56, November 2013, Pages 1570-1579
Engineering Structures

Risk-based seismic performance assessment of Yielding Shear Panel Device

https://doi.org/10.1016/j.engstruct.2013.07.032Get rights and content

Highlights

  • Seismic performance of yielding shear panel device (YSPD) is evaluated.

  • Probabilistic performance evaluation techniques are used.

  • Uncertainties of seismic demand and structural capacity are considered.

  • Effect of varying seismicity is reflected through considering multiple sites.

  • Various size and configuration of YSPDs are utilized for the analysis.

Abstract

Yielding Shear Panel Devices (YSPDs) have recently been proposed to facilitate passive energy dissipation of building frames during seismic activity and hence protect major structural components from excessive stress. A YSPD is composed of a thin steel diaphragm plate encapsulated within a square hollow steel tube, which is bolted to the structure to utilize the inelastic shear deformation capability of the steel diaphragm plate for energy dissipation and for consequent modification to the structural response. This paper conducts probabilistic performance evaluation to assess the appropriateness of YSPDs given uncertainty in the occurrence and intensity of earthquakes, material strength, stiffness, structural response, etc., and evaluate performance based on size, number and configuration of YSPDs. A fragility analysis is conducted, which identifies the probability of exceeding a structural damage level depending on ground motion intensity, along with a limit state probability analysis to quantify the annual exceedance probability of a specified damage level. A mathematical model to represent YSPDs in a finite element code is developed and the model is used for analyzing a case study steel moment frame with alternative YSPD designs. The study reveals the potential for considerable reduction in the median fragility and annual limit state exceedance probability due to the inclusion of YSPDs through a V-brace system. However, the effectiveness of different YSPD orientations is varied and their relative performance levels are discussed in detail. Overall, the study shows the suitability of YSPD as a passive energy dissipation device and the potential to utilize this device to help achieve performance-based objectives for buildings in seismic zones.

Introduction

Recent seismic activities around the globe have revealed the need to identify sustainable solutions for reducing the catastrophic impacts of earthquakes. Researchers have introduced a variety of active, semi-active and passive energy dissipation devices to diminish the damaging seismic effects. Passive control mechanisms received attention due to their simplicity in design as well as some additional unique advantages over other control mechanisms. For example, passive control devices are generally more reliable due to their independence of external power, are easy to rehabilitate, economical and less complex. Some commonly used metal yielding passive energy dissipating devices include the added damping and stiffness (ADAS) device [1], [2], [3], triangular added damping and stiffness (TADAS) device [4], [5], steel plate shear wall (SPSW) [6], [7], among others. These metal yielding devices utilise the stable hysteretic response of the constituent materials to dissipate energy.

The Yielding Shear Panel Device (YSPD) [8], [9] is another recently proposed metal yielding energy dissipating device as shown in Fig. 1. YSPD dissipates energy by taking advantage of its stable hysteretic in-plane shear deformation of the steel diaphragm plate. YSPD is composed of a steel diaphragm plate welded inside a steel square hollow section (SHS). SHS provides the supporting boundary for the diaphragm plate as well as connectivity with the V-brace and the beam through bolted connection. Previous studies have focused on the device development, numerical modelling and response assessment in a deterministic fashion [9], [10], [11], [12]. Uncertainties arising from the occurrence and intensity of earthquakes, material strength and stiffness, structural response and consequences were not considered for the performance evaluation of YSPDs. Probabilistic seismic performance evaluation techniques, such as seismic fragility analysis and limit state probability analysis, consider these uncertainties and have been used to evaluate the performance of various seismic retrofit techniques for buildings and bridges [13], [14]. This paper uses a probabilistic approach to assess the performance of YSPDs using a benchmark structure to provide insights into the relative performance of an as-built and YSPD retrofitted structure. Uncertainties associated with seismic intensity and structural responses are considered for probabilistic performance evaluation of YSPDs. Probabilistic tools such as fragility curves and point estimates of risk of damage are used to uncover the impacts of these uncertainties and subsequently identify the performance of YSPDs for different design configurations. Obtained results provide some useful insight into changes in the probabilistic performance of a structure as a result of change in the device size and their relative positioning within the structure. It is worth noting that for other building configurations the probabilistic performance may vary based on the building design and the arrangement of YSPDs.

Section snippets

Structural model for seismic performance assessment

The moment resisting frame of the Los Angeles (LA) three storey SAC model structure, designed for the SAC Phase II Steel Project [15], [16] has been used by many researchers for performance evaluation of various seismic control devices [17], [18], [19], [20]. The four bayed North–South lateral load-bearing moment resisting frame of this benchmark structure is chosen to evaluate the performance of YSPD. Fig. 2 shows the floor plan and the moment resisting frame of the three storey SAC model

YSPDs within the moment resisting frame

Hossain and Ashraf [12] used the Bouc–Wen–Baber–Noori (BWBN) model [23] to represent the pinching hysteretic force deformation relationship of YSPDs and provided closed-form relationships among the physical parameters and model parameters. Haukaas and Der Kiureghian [24] implemented the BWBN model in Opensees [21] as a uni-axial material model excluding the pinching effect. This existing code is modified to incorporate the pinching effect herein for probabilistic seismic performance assessment

Probabilistic seismic performance evaluation

Probabilistic seismic performance evaluation identifies the response of a structure considering the uncertainties associated with the seismic events and the subsequent structural responses. The limit state, which is denoted by damage state (DS), probability of the seismic risk assessment is defined by Eq. (1) assuming seismic intensity demand (Q) and structural capacity (R) as random variables [25].PLS=xP[DS|Q=x]·P[Q=x]where P[DS|Q = x] represents the seismic fragility of the structure and P[Q = x

Performance based on seismic drift demand assessment

The drift demand for design ground motion intensity for LA (Sa = 0.72 for T1 = 1 s) are compared to identify the reduction for various size and configurations of YSPDs and plotted in Fig. 7. A significant reduction in the seismic drift demand is observed after introducing YSPDs. The dispersion of seismic demand (βD|Sa) is also shown for these configurations. The minimum median demand reduction of 3.3% is attained by YSPD 100 × 4 × 2 (Case 1) and a maximum reduction of 23.6% of the seismic drift demand

Conclusion

Probabilistic seismic performance evaluation techniques are employed herein to assess the suitability of Yielding Shear Panel Device as a passive control device. An incremental dynamic analysis has been conducted using a suite of available earthquake records and a finite element model of the SAC building [16] with a recently calibrated BWBN model [23], [33] introduced in the OpenSees platform to reflect the behaviour of the Yielding Shear Panel Device. Results obtained from the nonlinear

References (35)

  • A.S. Whittaker

    Seismic testing of steel plate energy dissipation devices

    Earthquake Spectra

    (1991)
  • Tsai KC, Hong CP. Steel triangular plate energy absorber for earthquake-resistant buildings. In: Constructional steel...
  • Timler P, Kulak GL. Experimental study of steel plate shear walls. Structural Engineering Report No. 114, Dept. of...
  • M. Williams et al.

    Monotonic and cyclic tests on shear diaphragm dissipators for steel frames

    Adv Steel Constr

    (2006)
  • M.R. Hossain et al.

    Numerical modelling of yielding shear panel device for passive energy dissipation

    Thin-Walled Struct

    (2011)
  • Z. Li

    Pinching hysteretic response of yielding shear panel device

    Eng Struct

    (2011)
  • J.E. Padgett et al.

    Methodology for the development of analytical fragility curves for retrofitted bridges

    Earthquake Eng Struct Dynam

    (2008)
  • Cited by (0)

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