scholarly journals Mathematical Expression of Design Hysteretic Energy Spectra Based on Chinese Soil Type

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Cuiling Ma ◽  
Qiang Gu ◽  
Guohua Sun
Keyword(s):  
Seismic Design ◽  
Soil Type ◽  
Damping Ratio ◽  
Mathematical Expression ◽  
Spectral Shape ◽  
Site Classification ◽  
Velocity Spectrum ◽  
Hysteretic Energy ◽  
Site Group ◽  
Ductility Ratio

This paper explores the energy-based seismic design based on source-to-site distance and the site classification found in Chinese national codes. Specifically, 750 ground motion records were selected according to Chinese site classification, and the equivalent velocity spectra of cumulative hysteretic energy (HE) demand were derived using the energy-balance equation with the single degree of freedom (SDOF) system. In addition, the effects of soil type, earthquake magnitude, site group, structural damping ratio, and ductility ratio were investigated on the HE spectra, and mathematical expression of the equivalent velocity spectrum was presented. The analysis of the HE spectra indicated that the HE spectra were significantly affected by the ground acceleration amplitude, soil type, site group, and damping ratio. The ductility ratio also had an impact on the spectral value, but no effect on the spectral shape. The effect of postyielding stiffness ratio (PYSR) on the spectral shape and spectral value could be neglected. The research findings shed new light on the seismic design based on HE spectrum.

scholarly journals A Normalized Hysteretic Energy Spectrum for Energy-Based Seismic Design

2020 ◽  
Vol 198 ◽  
pp. 04004
Author(s):  
Cuiling Ma ◽  
Changbing Chen ◽  
Xiaotang Lv ◽  
Jian Bian ◽  
Yuan Feng ◽  
...  
Keyword(s):  
Seismic Design ◽  
Soil Type ◽  
Damping Ratio ◽  
Site Classification ◽  
Single Degree Of Freedom ◽  
Hysteretic Energy ◽  
Type Site ◽  
Set Up ◽  
Ground Motion Records ◽  
Ductility Ratio

To disclose the impacts of hysteretic energy (HE) demand on energy-based seismic design, this paper introduces the dimensionless parameter βEH to express the cumulative HE indirectly and establishes the βEH spectrum for energy-based seismic design. After analyzing numerous seismic responses of a single degree-of-freedom (SDOF) system, the author set up a simplified βEH spectral formula based on the genetic algorithm. Then, 750 ground motion records were selected according to Chinese site classification, and used to examine the effects of soil type and damping ratio on the βEH spectra. The results show that the soil type, site group and damping ratio have significant effects on the βEH spectra; the ductility ratio has an impact on the spectral value but not the spectral shape.

scholarly journals Energy-Based Seismic Design Method for EBFs Based on Hysteretic Energy Spectra and Accumulated Ductility Ratio Spectra

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Cuiling Ma
Keyword(s):  
Seismic Design ◽  
Design Method ◽  
Time History ◽  
Soil Classification ◽  
Nonlinear Static Analysis ◽  
Energy Spectra ◽  
Hysteretic Energy ◽  
Shear Links ◽  
Seismic Design Method ◽  
Ductility Ratio

In the case of far field earthquakes, structural failure often results from accumulated damage caused by cyclic effects and gradual accumulation of energy. This paper proposes an energy-based seismic design method for steel eccentrically braced frames (EBFs) with two shear links at every story according to the energy balance concept. The proposed method is theoretically supported by hysteretic energy spectra and accumulated ductility ratio spectra according to the Chinese soil classification. Furthermore, the method can be used to clarify the relationship between cumulative hysteretic energy and one-way pushover energy. For developing the method, it is assumed that all the hysteretic energy is dissipated by the shear links, column bases, and beam ends of the frames at both sides. Therefore, the parts outside the links, including beam segments, braces, and columns, are specially designed to perform elastically during an earthquake. Furthermore, a V-scheme steel EBF with ten stories and three spans is designed. The seismic performances of the designed structure, such as story drift and energy dissipation, are evaluated by nonlinear static analysis and time-history analysis. Finally, the reliability and accuracy of the proposed seismic design method are validated.

Spectral damping scaling factors for horizontal components of ground motions from subduction earthquakes using NGA-Subduction data

2021 ◽  
pp. 875529302110279
Author(s):  
Sanaz Rezaeian ◽  
Linda Al Atik ◽  
Nicolas M Kuehn ◽  
Norman Abrahamson ◽  
Yousef Bozorgnia ◽  
...  
Keyword(s):  
Ground Motions ◽  
Damping Ratio ◽  
Spectral Shape ◽  
Parametric Models ◽  
Scaling Factors ◽  
Global Models ◽  
Motion Models ◽  
Subduction Earthquakes ◽  
Crustal Earthquakes ◽  
Subduction Zone Earthquakes

This article develops global models of damping scaling factors (DSFs) for subduction zone earthquakes that are functions of the damping ratio, spectral period, earthquake magnitude, and distance. The Next Generation Attenuation for subduction earthquakes (NGA-Sub) project has developed the largest uniformly processed database of recorded ground motions to date from seven subduction regions: Alaska, Cascadia, Central America and Mexico, South America, Japan, Taiwan, and New Zealand. NGA-Sub used this database to develop new ground motion models (GMMs) at a reference 5% damping ratio. We worked with the NGA-Sub project team to develop an extended database that includes pseudo-spectral accelerations (PSA) for 11 damping ratios between 0.5% and 30%. We use this database to develop parametric models of DSF for both interface and intraslab subduction earthquakes that can be used to adjust any subduction GMM from a reference 5% damping ratio to other damping ratios. The DSF is strongly influenced by the response spectral shape and the duration of motion; therefore, in addition to the damping ratio, the median DSF model uses spectral period, magnitude, and distance as surrogate predictor variables to capture the effects of the spectral shape and the duration of motion. We also develop parametric models for the standard deviation of DSF. The models presented in this article are for the RotD50 horizontal component of PSA and are compared with the models for shallow crustal earthquakes in active tectonic regions. Some noticeable differences arise from the considerably longer duration of interface records for very large magnitude events and the enriched high-frequency content of intraslab records, compared with shallow crustal earthquakes. Regional differences are discussed by comparing the proposed global models with the data from each subduction region along with recommendations on the applicability of the models.

scholarly journals Increment of Steel Tonnage for Reinforced Concrete School Building Considering Seismic Design

2019 ◽  
Vol 8 (3S3) ◽  
pp. 351-355
Keyword(s):  
Reinforced Concrete ◽  
Seismic Design ◽  
Soil Type ◽  
Research Work ◽  
Variable Parameter ◽  
Peninsular Malaysia ◽  
School Building ◽  
Ground Acceleration ◽  
Seismic Fault ◽  
Moderate Earthquake

A series of Indonesian earthquakes, especially from Sumatra caused vibration on buildings in Peninsular Malaysia like Kuala Lumpur and Penang Island. In East Malaysia, Sabah state has been classified as a region with active local seismic fault. A moderate earthquake with Mw6.1 was occurred in Ranau on 5th June 2015 and caused damage on buildings either the structural or non-structural members. Hence, the implementation of seismic design on new buildings is important to ensure public safety. However, such action has its own pro and contra especially when dealing with cost. Therefore, current research work presents the influence of seismic design consideration on the increment of cost for steel reinforcement. For that purpose, a four storey reinforced concrete school building was generated and used as basic model for analysis, design, and taking off. Two level of seismicity representing by the reference peak ground acceleration, αgR equal to 0.07g and 0.10g has been taken into account in the structural analysis and seismic design process. Besides, three soil type namely as soil type A, soil type C, and soil type E also has been considered as variable parameter. Based on result, total steel tonnage in beams for models considering seismic design increases around 14% to 119% higher than the model without seismic design. For columns, the increment is around 13% to 155%. Generally, total cost of steel used as for concrete reinforcement of the whole structure increases around 13% to 131% depending on the level of seismicity and soil type.

The Research on Hysteretic Energy in the Equivalent System Schemes between Multi Degree of Freedom System and Single Degree of Freedom System

2012 ◽  
Vol 166-169 ◽  
pp. 2177-2181
Author(s):  
Ming Qiang Sheng ◽  
Ying Liu
Keyword(s):  
Seismic Design ◽  
Seismic Waves ◽  
Good Alternative ◽  
Cumulative Damage ◽  
Degree Of Freedom ◽  
Equivalent System ◽  
Single Degree Of Freedom ◽  
Hysteretic Energy ◽  
Single Degree ◽  
Comparison And Analysis

The cumulative damage produced by severe earthquake is significant to the structural dilapidation and collapse. Most design methods based on force or displacement can’t reflect the effect of cumulative damage. Energy-based seismic design is known as a good alternative design. At present the research on the hysteretic energy of single-degree of freedom system(SDOF) is abundant, but real buildings can only be simplified as multi-degree of freedom systems(MDOF) mostly. Therefore how to acquire suitable equivalent single-degree of freedom system(ESDOF) is a key program. In this paper 12 equivalent system schemes(ESS) have been put forward, then the ratio of hysteretic energy(RH) of 6-floors framework was calculated with 30 typical seismic waves. Based on the comparison and analysis between calculations of 3 typical ESS, by the way of envelope fitting, the expression of RH related to earthquake characteristic value a/v was established.

Effects of Site Classification on Platform Value of Response Spectrum

2011 ◽  
Vol 378-379 ◽  
pp. 306-309
Author(s):  
Ping Li ◽  
Jing Shan Bo ◽  
Xiao Yun Guo ◽  
You Wei Sun ◽  
Yu Dong Zhang
Keyword(s):  
Ground Motion ◽  
Seismic Design ◽  
Wave Motion ◽  
Response Spectrum ◽  
Equivalent Linearization ◽  
Earthquake Response ◽  
Response Analysis ◽  
Site Classification ◽  
Earthquake Motion ◽  
Design Response Spectrum

Regarding the design response spectrum in the code for seismic design of buildings as target spectra，the 28 acceleration histories are formed artificially．They are used as the inputs ground motion in earthquake response analysis．Four site classifications profiles were selected or constructed from practical site profiles．With the use of 1-D equivalent linearization wave motion method that is wildly used at present in site seismic response analysis, the platform values of surface response spectrum for different profiles under different ground motion inputs were calculated．Different platform values of the response spectrum and relational expression which is seven input earthquake motion intensity and site classifications have been given by statistical analysis.

Response Characteristics of Piping System Supported by Visco-Elastic and Elasto-Plastic Dampers

1990 ◽  
Vol 112 (1) ◽  
pp. 34-38 ◽  
Author(s):  
T. Chiba ◽  
H. Kobayashi
Keyword(s):  
Energy Dissipation ◽  
Seismic Design ◽  
Damping Ratio ◽  
The Other ◽  
Piping System ◽  
Response Level ◽  
Response Characteristics ◽  
Damping Effect ◽  
Component Test ◽  
Piping Systems

Improving the reliability of the piping systems can be achieved by eliminating the mechanical snubber and by reducing the response of the piping. In the seismic design of piping system, damping is one of the important parameters to reduce the seismic response. It is reported that the energy dissipation at piping supports contributes to increasing the damping ratio of piping system. Visco-elastic damper (VED) and elasto-plastic damper (EPD) were developed as more reliable, high-damping piping supports. The dynamic characteristics of these dampers were studied by the component test and the full-scale piping model test. Damping effect of VED is independent of the piping response and VED can be modeled as a complex spring in the dynamic analysis. On the other hand, damping ratio of piping system supported by EPD increases with the piping response level. So, these dampers are helpful to increase the damping ratio and to reduce the dynamic response of piping system.

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