Intensity Measure Correlations Observed in the NGA-West2 Database, and Dependence of Correlations on Rupture and Site Parameters

2017 ◽  
Vol 33 (1) ◽  
pp. 145-156 ◽  
Author(s):  
Jack W. Baker ◽  
Brendon A. Bradley
Keyword(s):  
Geometric Mean ◽  
Condition Dependence ◽  
Peak Ground Velocity ◽  
Spectral Acceleration ◽  
Intensity Measure ◽  
Ground Acceleration ◽  
Correlation Models ◽  
Continued Use ◽  
S Peak ◽  
Ground Motion Intensity Measure

This manuscript reports ground motion intensity measure ( IM) correlations for a number of IM types, as measured from the NGA-West2 database. IMs considered are Spectral Accelerations with periods from 0.01 s to 10 s, Peak Ground Acceleration, Peak Ground Velocity, and Significant Duration (for 5–75% and 5–95% definitions). Results are shown for correlations of both maximum-direction and geometric mean spectral acceleration values, given the need for such maximum-direction correlations in a new ASCE 7-16 procedure. Additionally, the potential magnitude-, distance- and site-condition-dependence of IM correlations are evaluated. The results are practically important as IM correlations are increasingly used in a range of engineering and seismic hazard calculations. We find that maximum-direction spectral correlations are comparable to correlations for other spectral acceleration definitions, and that the correlations have no practically significant dependence on magnitude, distance or site conditions. These results support the collective understanding that IM correlations are stable across a range of conditions, and as a result, that existing correlation models are generally appropriate for continued use in engineering calculations.

Correlation of spectral acceleration values of vertical and horizontal ground motion pairs

2020 ◽  
Vol 36 (4) ◽  
pp. 2112-2128
Author(s):  
Mohsen Kohrangi ◽  
Athanasios N Papadopoulos ◽  
Paolo Bazzurro ◽  
Dimitrios Vamvatsikos
Keyword(s):  
Ground Motion ◽  
Peak Ground Acceleration ◽  
Correlation Coefficients ◽  
Peak Ground Velocity ◽  
Coefficient Estimates ◽  
Ground Acceleration ◽  
Intensity Measures ◽  
Correlation Models ◽  
Horizontal Ground Motion ◽  
S Peak

We present correlation coefficient estimates between a number of ground motion intensity measures ( IMs), as measured from the NGA-West2 database, with focus on the correlation of vertical–vertical and vertical–horizontal ground motion components. The IMs considered include spectral accelerations with periods from 0.01 to 10 s, peak ground acceleration, peak ground velocity, and significant duration (for 5%–75% and 5%–95% definitions). To facilitate their use, parametric equations are also fitted to the correlation models. Finally, the dependence of the obtained correlation coefficients to magnitude, distance, and Vs30 is evaluated.

scholarly journals Study on the Seismic Effect of the Interbedded Soil Layer in the Yinchuan Alluvial Plain

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Shun Yang ◽  
Xin Han ◽  
Qiyun Lei ◽  
Sihan Yu ◽  
Chao Liu
Keyword(s):  
Seismic Response ◽  
Soil Layer ◽  
Peak Ground Velocity ◽  
Equivalent Linearization ◽  
Silty Clay ◽  
Spectral Acceleration ◽  
Ground Acceleration ◽  
Soil Layers ◽  
Amplification Effect ◽  
Soil Model

This paper presents a numerical analysis of two types of representative site profiles in the Yinchuan Plain under earthquake loading. The analyzed soil profiles, based on borehole investigations performed over the years, are used to explore the seismic response of the sites in this area. In total, eleven stratified soil models are used in this study, which can be grouped into two categories: a single interbedded soil model and multiple interbedded soil model. A one-dimensional equivalent linearization method is applied to evaluate the seismic response of different soil models under four exceeding probabilities in terms of peak ground acceleration (PGA), peak ground velocity (PGV), peak ground displacement (PGD), and spectral acceleration (Sa). The results show that the significant amplification effect of PGA occurs in rare and extremely rare earthquakes, with an amplification ratio of 1.4∼1.7 when the single silty clay layer is located at the model ground. In this scenario, the spectral acceleration is amplified at a period of approximately 1.0 s. For the multilayered soil cases, the amplification effect tends to decrease, whereas the characteristic periods increase with increasing numbers of soil layers and the ground acceleration is deamplified under a high motion intensity when the number of soil layers is ≥ 5. This study, to a certain degree, has reference value for seismic microzonation in this area.

scholarly journals Seismic Hazard Assessment for Thuong Tan-Tan My Quarries (Vietnam)

2020 ◽  
Vol 1 (2) ◽  
Author(s):  
Cao Dinh Trong ◽  
Xuan-Nam BUI ◽  
Pham NAM HUNG ◽  
Thai ANH TUAN ◽  
Mai XUAN BACH ◽  
...  
Keyword(s):  
Seismic Hazard ◽  
Hazard Assessment ◽  
Peak Ground Acceleration ◽  
Seismic Hazard Assessment ◽  
Earthquake Hazard ◽  
Peak Ground Velocity ◽  
Ground Displacement ◽  
Ground Acceleration ◽  
Probability Of Exceedance ◽  
S Peak

This paper presents the seismic hazard assessment for Thuong Tan-Tan My quarries in Di An commune, Binh Duong province, Vietnam. Combination methods of gravity and magneto-telluric were used to estimate the dip angle and the width of the seismic source. The highest water column of 160 m will cause direct stress on the reservoir bottom with a maximum value of 1535.600 kPa and Coulomb stress of 68.693 kPa (at a depth of 2 km). The typical components of natural earthquake hazard (Mn.max = 5.0, depth of 10 km) in Thuong Tan - Tan My reservoir have the following values: peak ground acceleration PGA = 0.073 g ÷ 0.212 g; peak ground velocity PGV = 2.662 cm/s ÷ 7.984 cm/s; peak ground displacement PGD = 0.706 cm ÷ 1.918 cm at 10% probability of exceedance in 50 years. The typical components of triggered earthquake hazard (Mtr.max = 3.5, depth of 6 km) in Thuong Tan - Tan My reservoir have the following values: peak ground acceleration PGA = 0.024 g ÷ 0.172 g; peak ground velocity PGV = 0 ÷ 5.484 cm/s; peak ground displacement PGD = 0.061 cm ÷ 0.461 cm at 10% probability of exceedance in 50 years.

scholarly journals Probabilistic seismic hazard assessment of the historical peninsula of Istanbul

2012 ◽  
Vol 12 (11) ◽  
pp. 3483-3493 ◽  
Author(s):  
G. Ç. Ince
Keyword(s):  
Seismic Hazard ◽  
Geographical Information Systems ◽  
Ground Movement ◽  
Geographical Information ◽  
Peak Ground Velocity ◽  
Exceedance Probability ◽  
Probabilistic Seismic Hazard Assessment ◽  
Spectral Acceleration ◽  
Ground Acceleration ◽  
Acceleration Parameter

Abstract. In order to design buildings that are resistant to earthquakes, first it is necessary to determine the parameters of ground motion. In this study, the earthquake seismic hazard analysis of the Old City Districts of Istanbul (Fatih and Eminonu) was probabilistically defined. For the analysis, the study zone was divided into 307 cells of 250 × 250 m using geographical information systems, and these cells were used in the mapping of all the data obtained. Then, for a building lifetime of 50 yr, the acceleration parameters of earthquake ground motions, peak ground acceleration, peak ground velocity, and spectral acceleration values of 0.2 s and 1 s were obtained at the bedrock level according to 10% and 40% exceedances. Additionally, in order to produce the artificial acceleration-time records of the ground movement in accordance with the NEHRP acceleration spectrum, the TARSCHTS computer simulation program was utilized. The results of the analysis showed that for the 10% probability of exceedance, the peak bedrock acceleration values ranged from 0.30 g to 0.40 g, and for the 40% exceedance probability the acceleration values ranged from 0.22 g to 0.17 g. The Ss 10% exceedance probability, calculated according to the spectral acceleration parameter, ranged from 0.67 g to 0.85 g and the spectral acceleration parameter S1 varied between 0.22 g–0.28 g. The Ss 40% exceedance probability, calculated according to the spectral acceleration parameter, ranged from 0.46 g to 0.38 g and the spectral acceleration parameter S1 varied from 0.12 g to 0.14 g.

Which Spectral Acceleration are you Using?

2006 ◽  
Vol 22 (2) ◽  
pp. 293-312 ◽  
Author(s):  
Jack W. Baker ◽  
C. Allin Cornell
Keyword(s):  
Seismic Risk ◽  
Hazard Analysis ◽  
Ground Motions ◽  
Geometric Mean ◽  
Response Analysis ◽  
Spectral Acceleration ◽  
Intensity Measure ◽  
Structure Response ◽  
Future Earthquake ◽  
Structural Engineers

Analysis of the seismic risk to a structure requires assessment of both the rate of occurrence of future earthquake ground motions (hazard) and the effect of these ground motions on the structure (response). These two pieces are often linked using an intensity measure such as spectral acceleration. However, earth scientists typically use the geometric mean of the spectral accelerations of the two horizontal components of ground motion as the intensity measure for hazard analysis, while structural engineers often use spectral acceleration of a single horizontal component as the intensity measure for response analysis. This inconsistency in definitions is typically not recognized when the two assessments are combined, resulting in unconservative conclusions about the seismic risk to the structure. The source and impact of the problem is examined in this paper, and several potential resolutions are proposed. This discussion is directly applicable to probabilistic analyses, but also has implications for deterministic seismic evaluations.

scholarly journals 70%-Damped Spectral Acceleration as a Ground Motion Intensity Measure for Predicting Highly Nonlinear Response of Structures

2019 ◽  
Vol 35 (2) ◽  
pp. 589-610 ◽  
Author(s):  
Kenny Buyco ◽  
Thomas H. Heaton
Keyword(s):  
Ground Motion ◽  
Nonlinear Response ◽  
Spectral Acceleration ◽  
Intensity Measure ◽  
Steel Moment Frame ◽  
Intensity Measures ◽  
Frame Building ◽  
Highly Nonlinear ◽  
Wide Range ◽  
Ground Motion Intensity Measure

We investigate 70%-damped spectral acceleration, Sa70%( T), as a ground motion intensity measure for predicting maximum interstory drift ratios of 0.03, 0.06, and 0.1 as well as collapse. We perform incremental dynamic analysis with 50 ground motions on 22 steel moment frame building models with heights of 3, 9, and 20 stories. We find that if T1 ≤ T ≤ 2 T1, Sa70%( T) is efficient and usually sufficient for the considered levels of highly nonlinear response. Sa70%(1.5 T1) is generally an efficient choice. We find that Sa70%( T) is similar to average spectral acceleration, Saavg, in many ways, as both intensity measures emphasize a wide range of periods in a ground motion when compared to Sa5%( T1). Sa70%( T) is equivalent to the peak of a ground motion's low-pass filtered acceleration, and this interpretation may be useful for estimating the potential of a ground motion to elicit a highly nonlinear response.

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