Attenuation of Hysteretic Energy Spectra of Strong Ground Motion

2012 ◽  
Vol 166-169 ◽  
pp. 2453-2456
Author(s):  
Mao Sheng Gong ◽  
Jing Sun ◽  
Li Li Xie
Keyword(s):  
Energy Demand ◽  
Ground Motions ◽  
Energy Spectra ◽  
Energy Structure ◽  
Site Class ◽  
Hysteretic Energy ◽  
Ductility Factor ◽  
Scenario Earthquakes ◽  
Nonlinear Regression Method ◽  
Strong Ground

Based on 266 strong ground motions from 15 significant earthquakes in California of America, the attenuation law of hysteretic spectra is established by using nonlinear regression method, and the effects of site class and ductility level on the hysteretic spectra constructed from the attenuation relationship are discussed in the paper. The results show that the site has significant effects on hysteretic energy spectra, and the more soft the site is, the more hysteretic energy structure will suffer from earthquake. Moreover, for ductility level scaled by ductility factor, the results show that structure with greater ductility factor can dissipate more input energy from the earthquake by means of the plastic deformation. The up limit design value of ductility factor for a structure is proposed as 4 because there is little difference between the hysteretic energy demand for ductility factor 4 and larger values. The hysteretic energy demand for structures at a given site in scenario earthquakes can be evaluated according to the results of the paper.

scholarly journals Hysteretic Energy Demand under Superposition of Bidirectional Ground Motions

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Feng Wang ◽  
Jialin Shi ◽  
Pengyan Chen
Keyword(s):  
Energy Demand ◽  
Ground Motions ◽  
Energy Balance Equation ◽  
Correction Coefficient ◽  
Earthquake Excitation ◽  
Period Range ◽  
Vertical Coordinate ◽  
Hysteretic Energy ◽  
Sdof System ◽  
Response History Analysis

To address the irrationality of making a structure subjected to bidirectional ground motions equivalent to an SDOF system, a new approach method is presented in this paper. The ratio between modal participation factors of the two components of the structure is expressed as γ, and the superposition of bidirectional ground motions is regarded as one-directional earthquake excitation for the equivalent SDOF system. Based on this, an energy balance equation is established, and a method used to estimate normalized hysteretic energy (NHE) is proposed. Analysis of the ratio between NHE (γ ≠ 0) and NHE (γ = 0) is suggested in order to analyze the influence of bidirectional ground motions on hysteretic energy demand, and then, “α1 = NHE (γ ≠ 0)/NHE (γ = 0)” is defined, and bidirectional ground motion records for different soil sites are selected for establishing superimposed excitations. In addition, the period range of 0–5 s for the energy spectrum is divided into 6 ranges. In each period range, the means of α1 are defined as α. The curves of α of constant ductility factors for different soil sites are established, in which α is the vertical coordinate and γ is the horizontal coordinate. Through nonlinear response history analysis, the influence of soil types at different sites, the ductility factor, the ratio of modal participation factors, and the period on the values of α are analyzed. According to the analytical results, correction coefficient αs (the simplified value of α) is obtained so that the hysteretic energy demand under bidirectional ground motions can be determined.

scholarly journals Hysteresis and Soil Site Dependent Input and Hysteretic Energy Spectra for Far-Source Ground Motions

2016 ◽  
Vol 2016 ◽  
pp. 1-29 ◽  
Author(s):  
Mebrahtom Gebrekirstos Mezgebo ◽  
Eric M. Lui
Keyword(s):  
Ground Motions ◽  
Time History ◽  
Response Spectra ◽  
Energy Spectra ◽  
Period Range ◽  
Hysteretic Energy ◽  
Soil Site ◽  
Large Period ◽  
Motion Effect ◽  
Nonlinear Time History

Earthquake input energy spectra for four soil site classes, four hysteresis models, and five ductility levels are developed for far-source ground motion effect. These energy spectra are normalized by a quantity called velocity index (VI). The use of VI allows for the creation of dimensionless spectra and results in smaller coefficients of variation. Hysteretic energy spectra are then developed to address the demand aspect of an energy-based seismic design of structures with 5% critical damping and ductility that ranges from 2 to 5. The proposed input and hysteretic energy spectra are then compared with response spectra generated using nonlinear time history analyses of real ground motions and are found to produce reasonably good results over a relatively large period range.

scholarly journals Broadband Strong-Motion Prediction for Future Nankai-Trough Earthquakes Using Statistical Green’s Function Method and Subsequent Building Damage Evaluation

2021 ◽  
Vol 11 (15) ◽  
pp. 7041
Author(s):  
Baoyintu Baoyintu ◽  
Naren Mandula ◽  
Hiroshi Kawase
Keyword(s):  
Green’S Function ◽  
Green's Function ◽  
Nankai Trough ◽  
Ground Motions ◽  
Building Damage ◽  
Steel Buildings ◽  
Ground Acceleration ◽  
Attenuation Relations ◽  
Strong Ground Motions ◽  
Strong Ground

We used the Green’s function summation method together with the randomly perturbed asperity sources to sum up broadband statistical Green’s functions of a moderate-size source and predict strong ground motions due to the expected M8.1 to 8.7 Nankai-Trough earthquakes along the southern coast of western Japan. We successfully simulated seismic intensity distributions similar to the past earthquakes and strong ground motions similar to the empirical attenuation relations of peak ground acceleration and velocity. Using these results, we predicted building damage by non-linear response analyses and find that at the regions close to the source, as well as regions with relatively thick, soft sediments such as the shoreline and alluvium valleys along the rivers, there is a possibility of severe damage regardless of the types of buildings. Moreover, the predicted damage ratios for buildings built before 1981 are much higher than those built after because of the significant code modifications in 1981. We also find that the damage ratio is highest for steel buildings, followed by wooden houses, and then reinforced concrete buildings.

Regional integrated energy system schemes selection based on risk expectation and Mahalanobis-Taguchi system

2021 ◽  
pp. 1-18
Author(s):  
Jiahang Yuan ◽  
Yun Li ◽  
Xinggang Luo ◽  
Lingfei Li ◽  
Zhongliang Zhang ◽  
...  
Keyword(s):  
Energy Demand ◽  
Choquet Integral ◽  
Subjective Evaluation ◽  
Risk Attitude ◽  
Energy System ◽  
Energy Utilization ◽  
Utilization Efficiency ◽  
Energy Structure ◽  
Fuzzy Measures ◽  
Integrated Energy System

Regional integrated energy system (RIES) provides a platform for coupling utilization of multi-energy and makes various energy demand from client possible. The suitable RIES composition scheme will upgrade energy structure and improve integrated energy utilization efficiency. Based on a RIES construction project in Jiangsu province, this paper proposes a new multi criteria decision-making (MCDM) method for the selection of RIES schemes. Because that subjective evaluation on RIES schemes benefit under criteria has uncertainty and hesitancy, intuitionistic trapezoidal fuzzy number (ITFN) which has the better capability to model ill-known quantities is presented. In consideration of risk attitude and interdependency of criteria, a new decision model with risk coefficients, Mahalanobis-Taguchi system and Choquet integral is proposed. Firstly, the decision matrices given by experts are normalized, and then are transformed to minimum expectation matrices according to different risk coefficients. Secondly, the weights of criteria from different experts are calculated by Mahalanobis-Taguchi system. Mobius transformation coefficients based on interaction degree are to calculate 2-order additive fuzzy measures, and then the comprehensive weights of criteria are obtained by fuzzy measures and Choquet integral. Thirdly, based on group decision consensus requirement, the weights of experts are obtained by the maximum entropy and grey correlation. Fourthly, the minimum expectation matrices are aggregated by the intuitionistic trapezoidal fuzzy Bonferroni mean operator. Thus, the ranking result according to the comparison rules using the minimum expectation and the maximum expectation is obtained. Finally, an illustrative example is taken in the present study to make the proposed method comprehensible.

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