Regression Analysis of Dynamic Parameters Based on Experimental Data of a New Seismic Isolation Layer

2011 ◽  
Vol 105-107 ◽  
pp. 523-526
Author(s):  
Fei Yao ◽  
Ke Liu ◽  
Shou Ping Shang
Keyword(s):  
Regression Analysis ◽  
Seismic Isolation ◽  
Least Squares Method ◽  
Lateral Displacement ◽  
Damping Ratio ◽  
Shake Table Tests ◽  
Isolation Layer ◽  
Lower Beam ◽  
Calculation Results ◽  
Input Acceleration

A new steel-asphalt composite seismic isolation layer is introduced briefly. Based on data of shake table tests, regression analysis by least squares method is adopted to analyze the natural frequency and the damping ratio of a new isolation layer. The calculation results show that the damping increases as the input acceleration increases because when PGA is relatively large, the lateral displacement of the isolation layer is large, the distance between the upper beam and the lower beam become smaller. The upper beam squeezes the asphalt ointment between it and brick piers. Part of the vertical load begins to transfer to the brick piers and friction occurs between brick piers and upper beam.. It is good for displacement limit of the structure.

scholarly journals Calculation of interval damping ratio under uncertain load in power system

2012 ◽  
Vol 60 (1) ◽  
pp. 151-158
Author(s):  
J. Xing ◽  
C. Chen ◽  
P. Wu
Keyword(s):  
Linear Programming ◽  
Power System ◽  
Optimization Model ◽  
Damping Ratio ◽  
Small Signal ◽  
Small Signal Stability ◽  
Signal Stability ◽  
Successive Linear Programming ◽  
Calculation Results ◽  
Lower Limits

Calculation of interval damping ratio under uncertain load in power system The problem of small-signal stability considering load uncertainty in power system is investigated. Firstly, this paper shows attempts to create a nonlinear optimization model for solving the upper and lower limits of the oscillation mode's damping ratio under an interval load. Then, the effective successive linear programming (SLP) method is proposed to solve this problem. By using this method, the interval damping ratio and corresponding load states at its interval limits are obtained. Calculation results can be used to evaluate the influence of load variation on a certain mode and give useful information for improvement. Finally, the proposed method is validated on two test systems.

Shaking Table Test Study on Mid-Story Isolation Structures

2012 ◽  
Vol 446-449 ◽  
pp. 378-381
Author(s):  
Jian Min Jin ◽  
Ping Tan ◽  
Fu Lin Zhou ◽  
Yu Hong Ma ◽  
Chao Yong Shen
Keyword(s):  
Seismic Response ◽  
Seismic Isolation ◽  
Shaking Table Test ◽  
Base Isolation ◽  
Shaking Table ◽  
Natural Period ◽  
Isolation System ◽  
Isolation Layer ◽  
Lead Rubber Bearing ◽  
Complex Structural

Mid-story isolation structure is developing from base isolation structures. As a complex structural system, the work mechanism of base isolation structure is not entirely appropriate for mid-story isolation structure, and the prolonging of structural natural period may not be able to decrease the seismic response of substructure and superstructure simultaneously. In this paper, for a four-story steel frame model, whose prototype first natural period is about 1s without seismic isolation design, the seismic responses and isolation effectiveness of mid-story isolation system with lead rubber bearing are studied experimentally by changing the location of isolation layer. Respectively, the locations of isolation layer are set at bottom of the first story, top of the first story, top of the second story and top of the third story. The results show that mid-story isolation can reduce seismic response in general, and substructure acceleration may be amplified.

Vertical Vibration Control of Series Isolation System under Near-Fault Earthquake

2014 ◽  
Vol 638-640 ◽  
pp. 1952-1955
Author(s):  
Q. Rong ◽  
Yan Sheng ◽  
Shi Xin Liu
Keyword(s):  
Seismic Waves ◽  
Damping Ratio ◽  
Vertical Vibration ◽  
Isolation Effect ◽  
Earthquake Intensity ◽  
Isolation System ◽  
Vertical Stiffness ◽  
Isolation Layer ◽  
Near Fault ◽  
Composite Disk

Series isolation system consists of rubber isolation bearings and composite disk springs, determination method of vertical stiffness and vertical damping of isolation layer is given. Entering the near-fault vertical seismic waves, the affect of isolation layer parameters and earthquake intensity on the isolation effect is studied. Studies have shown that the vertical isolation effect increases with the increase of vertical damping ratio. When the damping ratio reaches a certain value, the isolated effect leveles off. When calculating model is adopted as the hierarchical model, vertical isolation effect has nothing to do with the increases of earthquake intensity.

A nonlinear regression analysis method based on Stakeholder Theory Model for performance evaluation of poverty reduction of agricultural operators

2019 ◽  
pp. 002072091989420
Author(s):  
Zhenmin Wang
Keyword(s):  
Regression Analysis ◽  
Performance Evaluation ◽  
Stakeholder Theory ◽  
Nonlinear Regression ◽  
Poverty Reduction ◽  
Least Squares Method ◽  
Theory Model ◽  
Analysis Method ◽  
Nonlinear Regression Analysis ◽  
Policy Supply

A nonlinear regression analysis method for performance evaluation of poverty reduction of agricultural operators based on Stakeholder Theory Model analysis was proposed to improve the effectiveness of performance evaluation of poverty reduction of a new type agricultural operator in poverty-stricken areas. Firstly, it can find out which interest demands of different stakeholders and which interest realization paths have significant impact on the task performance and peripheral performance of the policy supply of new agricultural operators through factor analysis and regression analysis of the questionnaire data of stakeholders to provide sufficient basis for the appropriate revision and adjustment of policy supply; secondly, the nonlinear regression model is established by using the nonlinear least squares method to fit, control, and forecast the performance evaluation of poverty reduction behavior of agricultural operators, which is more accurate than linear regression in both object and method. Finally, the effectiveness of the proposed algorithm is verified by empirical analysis.

Comparative Analysis of the Influence of Different Construction Technology for Excavation on Adjacent Tunnels

2014 ◽  
Vol 638-640 ◽  
pp. 884-887
Author(s):  
Yong Gang Du ◽  
Jing Cao ◽  
Zu De Ding
Keyword(s):  
Lateral Displacement ◽  
Internal Force ◽  
Calculation Model ◽  
Construction Technology ◽  
Tunnel Structure ◽  
Lateral Deformation ◽  
Foundation Pit ◽  
Engineering Construction ◽  
Excavation Process ◽  
Calculation Results

Based on the project of a foundation pit engineering adjacent to existing tunnel of Kunming metro line 1, a 3D calculation model is established in consideration the interaction of foundation pit support structures, tunnel structure and soil. In this paper, the authors have simulated the foundation pit excavation process in three conditions, and analyzed the changing laws of the lateral displacement and internal force of the tunnel induced by adjacent excavation under different conditions. Calculation results show that the distributions and the values of the displacement and internal force of the tunnel are obviously different under three different construction technologies, and the “jump dig” is the optimum excavation scheme due to the restriction in the excavation of foundation pit, and the lateral deformation of tunnel structure is smallest in this condition. The conclusion can provide a theoretical basis for similar excavation engineering construction.

Simulating Maximum and Residual Displacements of RC Structures: II. Sensitivity

2011 ◽  
Vol 27 (4) ◽  
pp. 1203-1218 ◽  
Author(s):  
Ufuk Yazgan ◽  
Alessandro Dazio
Keyword(s):  
Damping Ratio ◽  
Time Integration ◽  
Integration Step ◽  
Discretization Scheme ◽  
Hysteretic Model ◽  
Step Size ◽  
Shake Table Tests ◽  
Rc Structures ◽  
Residual Displacements ◽  
Response History Analysis

The simulated response of a structure subjected to seismic excitation is sensitive to the idealizations made to model its response. This paper examines critical idealizations and assumptions that have a strong influence on the accuracy of the maximum and residual displacements predicted by response-history analysis. A set of shake table tests are numerically reproduced for this purpose. The investigated idealizations include the discretization scheme, the axial load, the steel hysteretic model, the viscous damping ratio, and the time-integration step size. The results indicate that the simulated residual displacements are significantly more sensitive to the model idealizations than the maximum displacements. It is found that the adopted discretization scheme and the utilized steel hysteresis model have very large influences on simulated residual displacements.

Research on Seismic Isolated Floor Slab with Damper and Rolling Base

2011 ◽  
Vol 105-107 ◽  
pp. 429-435
Author(s):  
Hai Jie Ge ◽  
Hui Wang ◽  
Dong Qi Gao
Keyword(s):  
Seismic Isolation ◽  
Dynamic Test ◽  
Building Structure ◽  
Wave Analysis ◽  
Scaled Model ◽  
Floor Slab ◽  
Floor Slabs ◽  
The World ◽  
Input Acceleration ◽  
New Form

Earthquake is one of the major threats towards building and non-building structure and various seismic isolation technologies have gained a good development all-round the world. Based on such a condition, a new form of seismic isolation technology is raised, which combine rolling bases and dampers to isolate floor slabs from quake wave. Analysis towards scaled model dynamic test shows that this seismic isolation technology for floor slabs can effectively reduce response acceleration of floor slabs, especially when frequency of input acceleration is high. While frequency of input acceleration is low, it has to be assured that when slab hits damper, the hitting should be soft so that the response acceleration can be controlled at a low level.

Displacement Equations Using Force Method for Frame-Composite Walls under Horizontal Loads

2011 ◽  
Vol 137 ◽  
pp. 106-112
Author(s):  
Cheng Hao Wu ◽  
Meng Guo ◽  
Yuan Jian Zhang
Keyword(s):  
Shear Deformation ◽  
Calculation Method ◽  
Lateral Displacement ◽  
Shear Walls ◽  
High Rise ◽  
Wall Structures ◽  
Calculation Results ◽  
Working Together ◽  
Composite Wall ◽  
Composite Walls

According to the special forms and mechanical behavior of frame-composite walls, displacement calculation method for frame-composite walls under horizontal loads is proposed in this paper. The model of frames and composite walls in parallel is adopted for considering working together of them. Cracking of filling blocks at middle and end elastic stages is taken into account. Based on material and structure mechanics theories, the displacement calculation method of frame-composite walls is derived from that of frame structures. The calculation results of the proposed method agree well with the test results of multi-grid composite wall with edge frame columns reinforced by steel. The displacement calculation method of frame-composite walls is compatible with that of frames and that of RC shear walls. The shear deformation of the frame-composite wall contributes most to the whole deformation. And the lateral displacement curves of middle to high-rise frame-composite wall structures are characterized by flexure-shear deformation. The proposed displacement calculation method for frame-composite wall structures can be used as a reference for structural design

Brief Introduction of Traditional Seismic Technology and Emerging Isolation Technology

2014 ◽  
Vol 1010-1012 ◽  
pp. 250-253
Author(s):  
Ji Yang Li ◽  
Wen Fang Zhang
Keyword(s):  
Control System ◽  
Seismic Response ◽  
Seismic Isolation ◽  
Passive Control ◽  
Base Isolation ◽  
Seismic Structure ◽  
Natural Period ◽  
Isolation Layer ◽  
Passive Seismic

Seismic can be divided into passive seismic and active seismic. Seismic isolation technology belong to the second type. Base isolation structure is defined by setting the isolation layer between the superstructure and foundation building, to extend the natural period architecture, increasing the damping to reduce structural seismic response. It is a passive control system. Compared with the traditional seismic structure, it mainly through the isolation layer to absorb and dissipate energy, reducing the response to the earthquake.

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