Sensitivity of the response of Box-Girder Seat-type bridges to the duration of ground motions arising from crustal and subduction earthquakes

Jawad Fayaz; Miguel Medalla; Farzin Zareian

doi:10.1016/j.engstruct.2020.110845

Sensitivity of the response of Box-Girder Seat-type bridges to the duration of ground motions arising from crustal and subduction earthquakes

Jawad Fayaz, Miguel Medalla, Farzin Zareian

Research output: Contribution to journal › Article › peer-review

6 Citations (Scopus)

Abstract

The design practice of Box-Girder Seat-Type (BGST) bridges in the Western U.S. is continuously evolving based on the results of advanced modeling and analysis techniques. This is mainly to help engineers and researchers to better understand the behavior of BGST bridges during seismic excitations. Within this backdrop, this study fills the gaps in the current knowledge of assessing the combined effect of strong motion duration and spectral shape on the response of bridges using a comprehensive set of numerical simulations and statistical analyses. Three-dimensional finite element models of two real BGST bridges are analyzed using a large set of ground motions obtained from crustal sources and subduction sources. By means of Step-wise regression – and other statistical procedures – the sensitivity of bridge response parameters to various ground motion parameters including Arias Intensity (I_a), RotD50 spectral acceleration at the bridge's first natural period (S_a(T₁)), Significant Duration (D_5-95), mid-frequency (f), the derivative of the mid-frequency (f’) and time at 30% of cumulated Arias Intensity (t_mid) are evaluated. Results indicate that in the case of ground motions arising from shallow crustal sources, I_a and S_a(T₁) are the best predictors of the bridge response, and strong motion duration (D_5-95) has no statistically meaningful impact on the response of bridges. However, it is observed that the D_5-95 of the ground motions ascending from the subduction sources highly affects the bridge response; utilizing D_5-95 alongside S_a(T₁), or I_a, can significantly increase the accuracy of bridge response estimates. Hence, it is concluded that D_5-95 is not an important ground motion intensity measure for ground motion selection for bridges located in areas with crustal earthquakes. In contrast, D_5-95 is important in subduction zone ground motions and must be given proper consideration in the design and analysis of BGST bridges.

Original language	English
Article number	110845
Journal	Engineering Structures
Volume	219
DOIs	https://doi.org/10.1016/j.engstruct.2020.110845
Publication status	Published - 15 Sept 2020
Externally published	Yes

Bibliographical note

Funding Information:
This study is based on work supported by the California Department of Transportation (Caltrans) under Award No. 65A0647 . This financial support is gratefully acknowledged. Any opinions, findings, and conclusions or recommendations expressed in this paper are those of the authors and do not necessarily reflect the views of sponsors. The authors acknowledge Dr. Yousef Bozorgnia’s assistance in providing a set of subduction zone ground motions.

Publisher Copyright:
© 2020 Elsevier Ltd

Access to Document

10.1016/j.engstruct.2020.110845

Cite this

@article{c385179e6feb4e6686bf578c7c9b0d08,

title = "Sensitivity of the response of Box-Girder Seat-type bridges to the duration of ground motions arising from crustal and subduction earthquakes",

abstract = "The design practice of Box-Girder Seat-Type (BGST) bridges in the Western U.S. is continuously evolving based on the results of advanced modeling and analysis techniques. This is mainly to help engineers and researchers to better understand the behavior of BGST bridges during seismic excitations. Within this backdrop, this study fills the gaps in the current knowledge of assessing the combined effect of strong motion duration and spectral shape on the response of bridges using a comprehensive set of numerical simulations and statistical analyses. Three-dimensional finite element models of two real BGST bridges are analyzed using a large set of ground motions obtained from crustal sources and subduction sources. By means of Step-wise regression – and other statistical procedures – the sensitivity of bridge response parameters to various ground motion parameters including Arias Intensity (Ia), RotD50 spectral acceleration at the bridge's first natural period (Sa(T1)), Significant Duration (D5-95), mid-frequency (f), the derivative of the mid-frequency (f{\textquoteright}) and time at 30% of cumulated Arias Intensity (tmid) are evaluated. Results indicate that in the case of ground motions arising from shallow crustal sources, Ia and Sa(T1) are the best predictors of the bridge response, and strong motion duration (D5-95) has no statistically meaningful impact on the response of bridges. However, it is observed that the D5-95 of the ground motions ascending from the subduction sources highly affects the bridge response; utilizing D5-95 alongside Sa(T1), or Ia, can significantly increase the accuracy of bridge response estimates. Hence, it is concluded that D5-95 is not an important ground motion intensity measure for ground motion selection for bridges located in areas with crustal earthquakes. In contrast, D5-95 is important in subduction zone ground motions and must be given proper consideration in the design and analysis of BGST bridges.",

author = "Jawad Fayaz and Miguel Medalla and Farzin Zareian",

note = "Funding Information: This study is based on work supported by the California Department of Transportation (Caltrans) under Award No. 65A0647 . This financial support is gratefully acknowledged. Any opinions, findings, and conclusions or recommendations expressed in this paper are those of the authors and do not necessarily reflect the views of sponsors. The authors acknowledge Dr. Yousef Bozorgnia{\textquoteright}s assistance in providing a set of subduction zone ground motions. Publisher Copyright: {\textcopyright} 2020 Elsevier Ltd",

year = "2020",

month = sep,

day = "15",

doi = "10.1016/j.engstruct.2020.110845",

language = "English",

volume = "219",

journal = "Engineering Structures",

issn = "0141-0296",

publisher = "Elsevier B.V.",

}

TY - JOUR

T1 - Sensitivity of the response of Box-Girder Seat-type bridges to the duration of ground motions arising from crustal and subduction earthquakes

AU - Fayaz, Jawad

AU - Medalla, Miguel

AU - Zareian, Farzin

N1 - Funding Information: This study is based on work supported by the California Department of Transportation (Caltrans) under Award No. 65A0647 . This financial support is gratefully acknowledged. Any opinions, findings, and conclusions or recommendations expressed in this paper are those of the authors and do not necessarily reflect the views of sponsors. The authors acknowledge Dr. Yousef Bozorgnia’s assistance in providing a set of subduction zone ground motions. Publisher Copyright: © 2020 Elsevier Ltd

PY - 2020/9/15

Y1 - 2020/9/15

N2 - The design practice of Box-Girder Seat-Type (BGST) bridges in the Western U.S. is continuously evolving based on the results of advanced modeling and analysis techniques. This is mainly to help engineers and researchers to better understand the behavior of BGST bridges during seismic excitations. Within this backdrop, this study fills the gaps in the current knowledge of assessing the combined effect of strong motion duration and spectral shape on the response of bridges using a comprehensive set of numerical simulations and statistical analyses. Three-dimensional finite element models of two real BGST bridges are analyzed using a large set of ground motions obtained from crustal sources and subduction sources. By means of Step-wise regression – and other statistical procedures – the sensitivity of bridge response parameters to various ground motion parameters including Arias Intensity (Ia), RotD50 spectral acceleration at the bridge's first natural period (Sa(T1)), Significant Duration (D5-95), mid-frequency (f), the derivative of the mid-frequency (f’) and time at 30% of cumulated Arias Intensity (tmid) are evaluated. Results indicate that in the case of ground motions arising from shallow crustal sources, Ia and Sa(T1) are the best predictors of the bridge response, and strong motion duration (D5-95) has no statistically meaningful impact on the response of bridges. However, it is observed that the D5-95 of the ground motions ascending from the subduction sources highly affects the bridge response; utilizing D5-95 alongside Sa(T1), or Ia, can significantly increase the accuracy of bridge response estimates. Hence, it is concluded that D5-95 is not an important ground motion intensity measure for ground motion selection for bridges located in areas with crustal earthquakes. In contrast, D5-95 is important in subduction zone ground motions and must be given proper consideration in the design and analysis of BGST bridges.

AB - The design practice of Box-Girder Seat-Type (BGST) bridges in the Western U.S. is continuously evolving based on the results of advanced modeling and analysis techniques. This is mainly to help engineers and researchers to better understand the behavior of BGST bridges during seismic excitations. Within this backdrop, this study fills the gaps in the current knowledge of assessing the combined effect of strong motion duration and spectral shape on the response of bridges using a comprehensive set of numerical simulations and statistical analyses. Three-dimensional finite element models of two real BGST bridges are analyzed using a large set of ground motions obtained from crustal sources and subduction sources. By means of Step-wise regression – and other statistical procedures – the sensitivity of bridge response parameters to various ground motion parameters including Arias Intensity (Ia), RotD50 spectral acceleration at the bridge's first natural period (Sa(T1)), Significant Duration (D5-95), mid-frequency (f), the derivative of the mid-frequency (f’) and time at 30% of cumulated Arias Intensity (tmid) are evaluated. Results indicate that in the case of ground motions arising from shallow crustal sources, Ia and Sa(T1) are the best predictors of the bridge response, and strong motion duration (D5-95) has no statistically meaningful impact on the response of bridges. However, it is observed that the D5-95 of the ground motions ascending from the subduction sources highly affects the bridge response; utilizing D5-95 alongside Sa(T1), or Ia, can significantly increase the accuracy of bridge response estimates. Hence, it is concluded that D5-95 is not an important ground motion intensity measure for ground motion selection for bridges located in areas with crustal earthquakes. In contrast, D5-95 is important in subduction zone ground motions and must be given proper consideration in the design and analysis of BGST bridges.

UR - http://www.scopus.com/inward/record.url?scp=85085954589&partnerID=8YFLogxK

U2 - 10.1016/j.engstruct.2020.110845

DO - 10.1016/j.engstruct.2020.110845

M3 - Article

AN - SCOPUS:85085954589

SN - 0141-0296

VL - 219

JO - Engineering Structures

JF - Engineering Structures

M1 - 110845

ER -

Sensitivity of the response of Box-Girder Seat-type bridges to the duration of ground motions arising from crustal and subduction earthquakes

Abstract

Bibliographical note

Access to Document

Other files and links

Fingerprint

Cite this