・!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "//www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">" [Civil Engineering]Seismic Performance Analysis of Dams|Analysis & Simulation Consulting Portal Site|KOZO KEIKAKU ENGINEERING Inc.

HOME > Services > Seismic Performance Analysis of Dams

Seismic Performance Analysis of Dams

Work Examples

Verification of the Seismic Performance of a RC Dam Pier and Examination of a Retrofit Plan


In this example, we verified the level 2 seismic performance of the dam reservoir pier, and examined the retrofit plan. Based on the results from the nonlinear push-over analysis by the finite element model and earthquake response analysis, we estimated the behavior and damages of the structure after the rebar yielding, and then calculated the required reinforcement amount.

【Diagram 1】shows the evaluation of the dam pier. Evaluation was done using the three-dimensional FEM model. For the rebar, we used the truss element, and applied the material with bilinear characteristics to rebar’s axial direction. The rebar shares the node with the three-dimensional solid element of concrete. We evaluated the expression of adhesion between rebar and concrete by the tension stiffening after a cracking occurred in the concrete model. As shown in the 【Diagram 2】, we applied the nonlinear characteristics of ADINA to the concrete part, and performed the push-over calculation until concrete crushed under compression. Also, we performed the concrete nonlinear earthquake response analysis using the input earthquake ground motions.

【Diagram 1】Analysis Model (FEM mesh)

【Diagram 1】Analysis Model (FEM mesh)

【Diagram 2】Concrete Stress-Strain Characteristics

【Diagram 2】Concrete Stress-Strain Characteristics



【Diagram 3-1】Nonlinear Push-Over Analysis Results (First Cracking)

【Diagram 3-2】Nonlinear Push-Over Analysis Results (Endpoint Destruction Condition)



n

【Diagram 4】Push-Over Analysis Results (Rebar Yield ・Plastic Strain Distribution)

n 【Diagram 5】Nonlinear Earthquake Response Analysis Results (Rebar Yield ・Axis Strain Time History)/

【Diagram 5】Nonlinear Earthquake Response Analysis Results (Rebar Yield ・Axis Strain Time History)



Based on the analysis results shown in 【Diagram 3】~【Diagram 5】, we proposed and examined the retrofit method. We performed a nonlinear finite element analysis on the retrofit plan, and from the analysis results, we confirmed the plasticity condition of the reinforcing steel plate at the end point.

We can perform the retrofit design and design improvement by utilizing the breakdown phenomenon captured by this examination.


Earthquake Response Analysis of a Concrete Dam by the Fluid-Structure Interaction


In this example, we examined the earthquake response taking into consideration the interaction between the dam water and levee in a concrete gravity dam at the time of an earthquake occurrence.

We modeled the levee using the two-dimensional plane solid element to take into consideration the concrete material nonlinear. We modeled the water using the potential fluid element. As for the attenuation, we considered that it occurs in proportion to the initial stiffness, with a 10% attenuation constant of the first natural frequency.

Earthquake Response that considers the Interaction between the dam water and dam levee (concrete nonlinear)

Concern Software

  • Commprehensive Finite Element System for Structure, CFD, EM,FSI,TMC,Multiphysics
    ADINA

↑Page Top