Introduction Nonlinear Static (Pushover) Analysis in ANSYS APDL
What is Nonlinear Static Analysis?
Linear vs Nonlinear Static Analysis
What is Pushover Analysis?
Material Nonlinearity
Geometric Nonlinearity (Large Displacement Effect)
Complete Nonlinear Modeling Workflow
Step-by-Step Frame Modeling
Solution Settings
Post Processing
Capacity Curve
Base Shear – Roof Displacement Curve
Seismic Behavior Factor
Strength Factor
Stiffness Factor
Ductility Factor
Energy Absorption
Modification (Behavior) Factor
Engineering Applications
Project Features
Who Should Use This Project?
Download Project Nonlinear Static (Pushover) Analysis in ANSYS APDL

Introduction of Nonlinear Static (Pushover) Analysis in ANSYS APDL

Nonlinear Static Analysis, commonly known as Pushover Analysis, is one of the most powerful structural analysis techniques used to evaluate the seismic performance of buildings and other structures.

Unlike Linear Static Analysis, Pushover Analysis allows engineers to investigate yielding, stiffness degradation, plastic hinge formation, and structural collapse mechanisms under increasing lateral loads.

This project provides a complete step-by-step tutorial in ANSYS APDL, from nonlinear model creation to the calculation of the seismic behavior factor from the Capacity Curve.

What is Nonlinear Static Analysis?

Nonlinear Static Analysis is a structural analysis method in which loads are applied incrementally while allowing the structure to experience nonlinear behavior.Nonlinear Static (Pushover) Analysis in ANSYS APDL

Unlike linear analysis, the structural stiffness changes continuously during loading because of:

Material yielding
Cracking
Plastic deformation
Large displacement effects
Geometric nonlinearity

The objective is to determine the complete structural response until the desired displacement or collapse mechanism is reached.

Linear vs Nonlinear Static Analysis

This project explains the differences between Linear and Nonlinear Static Analysis.

Linear Static Analysis

Linear elastic material
Constant stiffness
Small displacement assumption
No yielding
No plastic behavior

Nonlinear Static Analysis

Material yielding
Stiffness degradation
Plastic deformation
Large displacement effects
Progressive structural response
Capacity Curve generation

Understanding these differences is essential before performing seismic performance evaluations.

What is Pushover Analysis?

Pushover Analysis is a nonlinear static procedure in which lateral loads are gradually increased until the target displacement is reached.

Nonlinear Static (Pushover) Analysis in ANSYS APDL

During the analysis, engineers evaluate:

Structural stiffness
Yield point
Plastic hinge development
Ultimate capacity
Collapse mechanism
Structural ductility
Energy dissipation

The primary output of a pushover analysis is the Capacity Curve (Base Shear vs Roof Displacement).

Material Nonlinearity

One of the key components of this project is Material Nonlinearity.Nonlinear Static (Pushover) Analysis in ANSYS APDL

The tutorial explains how nonlinear constitutive models are incorporated into ANSYS APDL to simulate:

Steel yielding
Plastic deformation
Reinforced concrete cracking
Concrete crushing
Progressive stiffness reduction

Material Nonlinearity enables the finite element model to reproduce the actual behavior of structures subjected to extreme loading conditions.

Geometric Nonlinearity (Large Displacement Effect)

The project also explains the importance of Large Displacement Effect.

When structural deformations become significant, the original geometry changes during loading, affecting the internal forces and structural stiffness.

Topics include:

Large Rotation
Large Displacement
Updated Geometry
Geometric Stiffness
P-Delta Effect
Stability Behavior

The tutorial demonstrates how to activate geometric nonlinearity in ANSYS APDL and explains when it should be considered in practical engineering analyses.

Complete Nonlinear Modeling Workflow

The project follows a professional engineering workflow:

Geometry Definition
Element Selection
Material Definition
Nonlinear Material Properties
Meshing Strategy
Boundary Conditions
Incremental Load Application
Nonlinear Solution Settings
Convergence Control
Post Processing
Capacity Curve Generation
Seismic Behavior Evaluation

Step-by-Step Frame Modeling

A complete 1-Bay 1-Story Frame is modeled from scratch.

The tutorial includes:

Geometry creation
Material assignment
Meshing
Load application
Nonlinear solution settings
Incremental loading
Result interpretation

Students can reproduce the entire nonlinear analysis process independently.

Solution Settings

Proper nonlinear solution settings are essential for achieving stable and accurate convergence.

Topics include:

Incremental loading
Load steps
Substeps
Convergence criteria
Newton-Raphson Iteration
Automatic Time Stepping
Large Deflection Option

These settings are explained in detail with practical recommendations for structural engineering problems.

Post Processing

After solving the nonlinear model, the tutorial demonstrates professional post-processing techniques, including:

Deformation Shapes
Plastic Regions
Von Mises Stress
Principal Stress
Plastic Strain
Reaction Forces
Load Step Results
Structural Response History

The project emphasizes engineering interpretation rather than simply displaying colorful contour plots.

Nonlinear Static (Pushover) Analysis in ANSYS APDL

Capacity Curve

The most important output of Pushover Analysis is the Capacity Curve.

The Capacity Curve relates:

Base Shear
Roof Displacement

This curve represents the global nonlinear behavior of the structure and serves as the basis for evaluating seismic performance.

The tutorial explains how to generate, interpret, and verify the Capacity Curve obtained from ANSYS APDL.

Base Shear – Roof Displacement Curve

The project demonstrates how to obtain the complete Base Shear – Roof Displacement Curve, including:

Elastic Region
Yield Point
Nonlinear Region
Ultimate Capacity
Softening Behavior

This curve is used to evaluate structural performance under seismic loading.

Calculate Seismic Behavior Factor

One of the unique features of this project is the calculation of the Seismic Behavior Factor (Behavior Factor / Modification Factor) directly from the Capacity Curve.

The tutorial explains the theoretical background and the complete calculation procedure.

Topics include:

Behavior Factor (R)
Response Modification Factor
Seismic Performance Evaluation
Capacity-Based Design

This section is rarely covered in conventional ANSYS training courses.

Strength Factor

The tutorial explains how structural overstrength contributes to the overall seismic behavior.

Topics include:

Yield Strength
Ultimate Strength
Overstrength Ratio

Stiffness Factor

Structural stiffness is evaluated throughout the nonlinear loading process.

The project explains:

Initial Stiffness
Secant Stiffness
Stiffness Degradation
Effective Stiffness

Ductility Factor

Ductility is one of the most important seismic performance indicators.

The tutorial demonstrates how to calculate:

Yield Displacement
Ultimate Displacement
Displacement Ductility Ratio

and explains its influence on structural safety.

Energy Absorption

Energy dissipation is evaluated using the area under the Capacity Curve.

The tutorial explains how structures absorb and dissipate earthquake energy through nonlinear deformation.

Modification (Behavior) Factor

Finally, all previously calculated parameters are combined to evaluate the Behavior (Modification) Factor, including:

Strength Contribution
Ductility Contribution
Energy Dissipation
Stiffness Characteristics

This provides engineers with a comprehensive understanding of structural seismic performance.

Engineering Applications

This project is applicable to:

Steel Buildings
Reinforced Concrete Structures
Seismic Assessment
Existing Building Evaluation
Structural Retrofit
Performance-Based Design
Capacity-Based Design
Earthquake Engineering Research

Project Features

This project includes:

Complete APDL source code
Full ANSYS project files
Step-by-step nonlinear modeling
Pushover Analysis
Material Nonlinearity
Large Displacement Effect
Capacity Curve generation
Base Shear–Roof Displacement Curve
Seismic Behavior Factor calculation
Engineering interpretation of results

Who Should Use This Project?

This project is ideal for:

Civil Engineers
Structural Engineers
Earthquake Engineers
Graduate Students
PhD Researchers
Performance-Based Design Engineers
ANSYS APDL Users
Finite Element Analysts

Download Project

Download this complete Nonlinear Static (Pushover) Analysis in ANSYS APDL project and learn how to model nonlinear structural behavior, generate capacity curves, evaluate seismic performance, and calculate the seismic behavior (modification) factor using professional finite element analysis techniques.

YouTube Video

🎥 Watch the complete YouTube tutorial to learn how to perform Nonlinear Static (Pushover) Analysis in ANSYS APDL. This project explains nonlinear modeling, material nonlinearity, large displacement effects, capacity curve generation, pushover analysis, and the calculation of the seismic behavior factor (Behavior/Modification Factor) from the capacity curve using real engineering examples.