A Multi-Peak Evolutionary Model for Stochastic Simulation of Ground Motions Based on Time-Domain Features

2018 ◽  
pp. 1-37 ◽  
Author(s):  
Zakariya Waezi ◽  
Fayaz R. Rofooei ◽  
M. Javad Hashemi
Keyword(s):  
Stochastic Simulation ◽  
Time Domain ◽  
Ground Motions ◽  
Evolutionary Model

Transient Analysis of Dam-Reservoir Interaction Based on Dynamic Stiffness of SBFEM

2011 ◽  
Vol 378-379 ◽  
pp. 213-217
Author(s):  
Shang Ming Li
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Time Domain ◽  
Transient Analysis ◽  
Ground Motions ◽  
Dynamic Stiffness ◽  
Dam Reservoir ◽  
The Time Domain ◽  
Infinite Reservoir ◽  
Element Method

The scaled boundary finite element method (SBFEM) was extended to solve dam-reservoir interaction problems in the time domain and a dynamic stiffness used in the SBFEM of semi-infinite reservoir in the time domain was proposed, which was evaluated by the Bessel function. Based on the dynamic stiffness, transient responses subjected to horizontal ground motions were analyzed through coupling the SBFEM and finite element method (FEM). A dam was modeled by FEM, while the whole fluid in reservoir was modeled by the SBFEM alone or a combination of FEM and SBFEM. Two benchmark examples were considered to check the accuracy of the dynamic stiffness. Results were compared with those from analytical or substructure methods and good agreements were found.

Temperature Rise Effect of Viscoelastically Damped Structures Under Strong Earthquake Ground Motions

1998 ◽  
Vol 14 (3) ◽  
pp. 125-135 ◽  
Author(s):  
K. C. Chang ◽  
M. H. Tsai ◽  
Y. H. Chang ◽  
M. L. Lai
Keyword(s):  
Energy Dissipation ◽  
Frequency Domain ◽  
Seismic Response ◽  
Time Domain ◽  
Temperature Rise ◽  
Strong Earthquake ◽  
Ground Motions ◽  
Domain Analysis ◽  
Effect Of Temperature ◽  
Earthquake Ground Motions

ABSTRACTViscoelastic (VE) dampers have been shown to be an effective energy dissipation device for structures subjected to seismic excitations. When a VE damper is under shear deformation, the temperature within the damper material will rise due to the conversion of mechanical energy into heat. The effect of temperature rise in the VE damper on a viscoelastically damped structure may be significant because the damper stiffness can decrease due to the temperature rise in the VE damper and its energy dissipation capacity may reduce under strong earthquake ground motions. This paper is intended to quantify the temperature rise effect. A VE element which can accurately describe the frequency and temperature dependent behavior of the test results of a VE damper is first presented. The effect of temperature rise within the VE material is included. Seismic response analyses of a viscoelastically damped structure which was studied extensively by shaking table tests are carried out by two analytical methods: a frequency domain analysis and a time domain analysis. Both analyses consider the effects of frequency and ambient temperature of the VE dampers. The frequency domain approach is computationally more efficient. However, it neglects the effect of temperature rise in the analysis. The time domain method is computationally less efficient. However, it can explicitly calculate the temperature rise during the earthquake and evaluate its influence on the structural responses. Finally, parametric studies on the effect of temperature rise within the VE damper material on the seismic response of a viscoelastically damped structure are analyzed and its implications on practical applications are discussed.

scholarly journals Generation of Uniform Hazard Spectrum Based on the Stochastic Method of Simulating Ground Motion and Its Use in Nuclear Power Plants

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Xueming Zhang ◽  
Weiming Yan ◽  
Haoxiang He ◽  
Yunlun Sun ◽  
Shicai Chen
Keyword(s):  
Stochastic Simulation ◽  
Nuclear Power ◽  
Power Plants ◽  
Hazard Analysis ◽  
Ground Motions ◽  
Site Effect ◽  
Element Model ◽  
Simulation Method ◽  
Stochastic Method ◽  
Uniform Hazard Spectrum

To obtain an accurate uniform hazard spectrum (UHS), this paper proposes combining a stochastic simulation with probabilistic seismic hazard analysis. The stochastic method fully accounts for the effect of the source mechanism, path, and site effect. Historical ground motions in the site specific to the nuclear power plant (NPP) are simulated, and a UHS with an equal exceeding probability is proposed. To compare the seismic performance of the NPP under different ground motions generated by the existing site spectrum (SL-2), the UHS generated by the safety evaluation report, and the US RG1.60 spectrum, respectively, a three-dimensional finite element model is established, and dynamic analysis is performed. Results show that the structural responses to different spectra varied; the UHS response was slightly larger than that of RG1.60. This finding is relatively more reasonable than prior research results. The UHS generated using the stochastic simulation method can provide a reference for the seismic design of NPPs.

Sign in / Sign up

Export Citation Format

Share Document