Analysis of Structural Parameters of MSCS on of the Overall Failure Probability of the Structure

2012 ◽  
Vol 256-259 ◽  
pp. 635-640
Author(s):  
Jian Jun Ye ◽  
Xun An Zhang ◽  
Xian Jie Wang
Keyword(s):  
Seismic Response ◽  
Dynamic Characteristics ◽  
Failure Probability ◽  
Structural Parameters ◽  
Seismic Intensity ◽  
Regular Pattern ◽  
Actual Design ◽  
Structural Mass ◽  
Overall Reliability

The randomness of value of tuned sub-structure mass and rigidity is comparatively large because of the needs of actual projects. Based on the dynamic characteristics and reliability of MSCS, the seismic response of the mega structure and the overall failure probability are discussed with the value of tuned sub structural mass and rigidity under different seismic intensity. It is shown that tuned sub structural mass and rigidity have significant affection on the overall reliability of structure, and seismic intensity has not interfere this regular pattern. Therefore, structural parameters of optimization which are referred to the regular pattern should be considered in the actual design in order to further enhance seismic capability of MSCS.

Structural Dynamic Characteristics Determination Using Response Data in Small Earthquakes

2011 ◽  
Vol 255-260 ◽  
pp. 1692-1695
Author(s):  
Mao Sheng Gong ◽  
Jing Sun ◽  
Li Li Xie
Keyword(s):  
Seismic Response ◽  
Dynamic Characteristics ◽  
Structural Control ◽  
Transfer Functions ◽  
Structural Parameters ◽  
Structural Dynamic ◽  
Low Level ◽  
Response Data ◽  
Structural Dynamic Characteristics ◽  
Time Invariant

The objective of the paper is to determine the structural dynamic characteristics from the low level structural seismic response data in small earthquakes. The off-line time-domain system identification method ARX (AutoRegressive with eXternal input) model is adopted to identify the time-invariant transfer functions, and then the structural parameters such as modal frequencies and damping ratios are determined. A 7-story reinforced concrete structure on which the strong motion monitoring system was installed and recorded seismic response in 3 small earthquakes was used for the analysis. It is found that the structural dynamic characteristics can be determined from low level acceleration response records in small earthquakes in which the structure can be assumed as a linear and time-invariant system. The results can be referenced by structure health monitoring, structural control and related works.

Floating Roof Influence on Seismic Response of Large Vertical Storage Tank

2013 ◽  
Vol 671-674 ◽  
pp. 1399-1402
Author(s):  
Ying Sun ◽  
Jian Gang Sun ◽  
Li Fu Cui
Keyword(s):  
Seismic Response ◽  
Storage Tank ◽  
Numerical Solutions ◽  
Fluid Pressure ◽  
Seismic Intensity ◽  
Site Conditions ◽  
Storage Tanks ◽  
Analysis Model ◽  
Base Shear ◽  
The Impact

To study the impact of floating roof on seismic response of vertical storage tank structure system subjected to seismic excitation, select 150000m3 storage tanks as research object, and the finite element analysis model of storage tanks with and without floating roof were established respectively. The seismic response of these two types of structure in different site conditions and seismic intensity were calculated and the numerical solutions were compared. The results show that floating roof has little impact on base shear and base moment in different site conditions and seismic intensity. Floating roof can effectively reduce the sloshing wave height. The influence of floating roof on dynamic fluid pressure decreases with the increase of seismic intensity, which is less affected by ground conditions.

Dynamic Characteristics Analysis of Cable-Rib Tension Deployable Antenna

2016 ◽  
Author(s):  
Liu Ruiwei ◽  
Hongwei Guo ◽  
Zhang Qinghua ◽  
Rongqiang Liu ◽  
Tang Dewei
Keyword(s):  
Dynamic Characteristics ◽  
Structural Parameters ◽  
Element Model ◽  
Structure Design ◽  
Antenna Structure ◽  
Characteristics Analysis ◽  
New Type ◽  
Dynamic Characteristics Analysis ◽  
The Finite Element Model ◽  
Weight Dynamic

Balancing stiffness and weight is of substantial importance for antenna structure design. Conventional fold-rib antennas need sufficient weight to meet stiffness requirements. To address this issue, this paper proposes a new type of cable-rib tension deployable antenna that consists of six radial rib deployment mechanisms, numerous tensioned cables, and a mesh reflective surface. The primary innovation of this study is the application of numerous tensioned cables instead of metal materials to enhance the stiffness of the entire antenna while ensuring relatively less weight. Dynamic characteristics were analyzed to optimize the weight and stiffness of the antenna with the finite element model by subspace method. The first six orders of natural frequencies and corresponding vibration modes of the antenna structure are obtained. In addition, the effects of structural parameters on natural frequency are studied, and a method to improve the rigidity of the deployable antenna structure is proposed.

The Dynamic Characteristics of Rigid Frame Single-Rib Arch Bridge

2013 ◽  
Vol 368-370 ◽  
pp. 1426-1430
Author(s):  
Li Xiong Gu ◽  
Rong Hui Wang
Keyword(s):  
Dynamic Characteristics ◽  
Bending Strength ◽  
Dynamic Properties ◽  
Structural Parameters ◽  
Bending Stiffness ◽  
Torsional Stiffness ◽  
Lateral Stiffness ◽  
Arch Bridge ◽  
Vertical Stiffness ◽  
Rigid Frame

In this paper, by establishing the finite element model to study the dynamic characteristics of rigid frame single-rib arch bridge. By respectively changing structural parameters of the span ratios, and the compressive stiffness of arch, and the bending stiffness of arch, and the bending stiffness of bridge girder, and the layout of boom to find out the regularity of the structure on lateral stiffness, and vertical stiffness, and torsional stiffness as well as dynamic properties, it come out the results of that lateral stiffness of the structure is weaker, and increasing the span ratios and the compressive strength of arch are conducive to the improvement of the overall stiffness, and improving the bending strength of arch and layout of boom are less effect on the overall stiffness and mode shape.

Seismic Reliability Analysis in the Framework of Metamodelling Based Monte Carlo Simulation

2017 ◽  
pp. 192-208 ◽  
Author(s):  
Shyamal Ghosh ◽  
Soham Mitra ◽  
Swarup Ghosh ◽  
Subrata Chakraborty
Keyword(s):  
Least Squares ◽  
Reliability Analysis ◽  
Response Surface ◽  
Seismic Response ◽  
Least Squares Method ◽  
Response Prediction ◽  
Seismic Intensity ◽  
Seismic Reliability ◽  
Moving Least Squares Method ◽  
Artificial Neural Network Ann

A comparative study of various metamodelling approaches namely the least squares method (LSM), moving least squares method (MLSM) and artificial neural network (ANN) based response surface method (RSM) are presented to demonstrate the effectiveness to approximate the nonlinear dynamic response of structure required for efficient seismic reliability analysis (SRA) of structures. The seismic response approximation by the LSM, MLSM and ANN based RSMs are explained with a brief note on the important issue of ground motion bin generation. The procedure adopted herein for SRA is based on the dual response surface approach. In doing so, the repetition of seismic intensity for SRA at different intensity levels is avoided by including this as one of the predictors in the seismic response prediction model. A nonlinear SDOF system has been taken up to elucidate the effectiveness of various metamodels in SRA.

Dynamic Simulation of Large Flow Solenoid Valve

2016 ◽  
Author(s):  
Z. Liu ◽  
X. Han ◽  
Y. F. Liu
Keyword(s):  
Dynamic Model ◽  
Dynamic Simulation ◽  
Dynamic Characteristics ◽  
Nonlinear Dynamic ◽  
Structural Parameters ◽  
Solenoid Valve ◽  
Simulation Software ◽  
Experimental Results ◽  
Nonlinear Dynamic Model ◽  
Large Flow

A nonlinear dynamic model of a large flow solenoid is presented with the multi-physics dynamic simulation software called SimulationX. Validation is performed by comparing the experimental results with the simulated ones. The dynamic characteristics of the large flow solenoid valve are analyzed. Different structural parameters are modified in this research and the diameter of the orifice is proved to be one of the most important parameters which influences the pressure response most.

Analyzing of Dynamic Characteristics of Special CNC Machine Tool

2010 ◽  
Vol 29-32 ◽  
pp. 2037-2041
Author(s):  
Ke Wang ◽  
Guang Lv ◽  
Xing Wei Sun
Keyword(s):  
Machine Tool ◽  
Dynamic Characteristics ◽  
Optimization Design ◽  
High Efficiency ◽  
Structural Parameters ◽  
Force Frequency ◽  
Cutting Method ◽  
Finite Element Software ◽  
Exciting Frequency ◽  
Motion Parameters

The dynamic characteristics of machine tool is an important factor, which make affect on the cutting stability of machine tool. The poor dynamic characteristics will seriously affect the stability of cutting, make the low cutting efficiency and low machining precision, and also accelerate the wear of tools and even reduce the machine’s service life. So it is necessary to analyze the dynamic characteristics of machine tool, and according to the results of analysis to optimize structural parameters and motion parameters of the machine tools. This paper analyses the dynamic characteristics of machine bed and machined work piece of the CNC special machine tool for Kelly with the finite element software, and analysis of excitation characteristics of cutting tool. It also makes optimization design to the machine bed, through the analysis and optimization, the natural frequency and stiffness will be obviously improved. According to the structure and calculation of the motion parameters we can get the exciting force frequency to workpiece when it is cut, using interlocking tooth cutting method to replace the initial symmetrical cutting method in order to avoid the resonance produced in the cutting process and improve stability. The exciting frequency when cutting can be improved and the probability of resonance when cutting is lowered. All these ensure high efficiency and high stability cutting.

Influence of Tie Beams of Pier on the Seismic Performance of a Continuous Rigid Frame Bridge with Twin-Legged Piers

2011 ◽  
Vol 368-373 ◽  
pp. 1105-1110
Author(s):  
Yun Jing Nie ◽  
Xu Yan ◽  
Tie Ying Li
Keyword(s):  
Seismic Response ◽  
Seismic Performance ◽  
Seismic Design ◽  
Dynamic Characteristics ◽  
Natural Frequencies ◽  
Continuous Rigid Frame Bridge ◽  
Analytical Results ◽  
Rigid Frame ◽  
Rigid Frame Bridge

In this paper, the influence of tie beams for piers is investigated on the dynamic characteristics and the seismic performance of a continuous rigid frame bridge with twin-legged piers. Modal analyses and the linear seismic response analyses are performed on a practical continuous rigid frame bridge with twin-legged piers with no tie beam, one tie beam and three tie beams of pier, using software Midas/civil. The findings indicate that installing tie beams of pier can increase the natural frequencies of this kind of bridge. Setting tie beams of pier is disadvantageous to the seismic performance of the bridge beam, but advantageous to improving the seismic performance of the twin-legged piers. The influence of tie beams of pier on the seismic performance on the whole structure is relevant to the pier height. These analytical results provide a reference for the seismic design and analysis of similar structures.

scholarly journals Vibroacoustic characteristics analysis of a planetary gear reducer considering the exterior housing structure

2021 ◽  
Vol 12 (1) ◽  
pp. 539-557
Author(s):  
Lihong Jin ◽  
Junpeng Shao ◽  
Xigui Wang ◽  
Yongmei Wang ◽  
Baixue Fu
Keyword(s):  
Numerical Simulation ◽  
Flow Field ◽  
Dynamic Characteristics ◽  
Optimization Design ◽  
Structural Parameters ◽  
Planetary Gear ◽  
Design Parameters ◽  
Weak Links ◽  
Acoustic Characteristics ◽  
Transfer Path

Abstract. Previous studies have attempted to identify weak links in the dynamic characteristics of the planetary gear reducer (PGR) exterior body structure (EBS). Through numerical simulation, these studies analyzed the mode and natural frequencies and the vibration types of each order of the EBS. However, these scholars have never focused on the main factors affecting the dynamic characteristics of the EBS of this subject. This study in the topic has analyzed the vibroacoustic characteristics of an EBS and optimized its design using numerical simulation. Herein, the contribution of the vibration transfer path from the excitation points on the exterior body to the machine foot is emphatically revealed, and the influences of the main structural parameters on the transfer characteristics are discussed. An optimal EBS for a PGR with lower acoustic vibrations is designed in detail, and a composite EBS with damping vibration attenuation and acoustic absorption is proposed. The radiation acoustic characteristics without acoustic protection and damping materials are analyzed. These research results are implemented in order to realize the dynamic characteristics, transmission, and radiation acoustic characteristics as objects of optimization, and the structural design parameters of the PGR exterior body are deeply optimized using dynamic modification and sensitivity analysis. This topic focuses on the vibroacoustic coupling of EBS in stationary fluid and average flow field. Based on the analysis method of theoretical modeling and numerical calculation, the EBS dynamic response and vibroacoustic characteristics under the action of frontal excitation external acoustic flow field are studied, which will be beneficial to explore the comprehensive optimization design of PGR dynamic and vibroacoustic properties.

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