Define scope
Confirm component boundaries, fatigue question, available data and engineering criteria.
Structural & Mechanical Engineering Support
Fatigue Analysis Services
Support for assessing cyclic loading, stress ranges and fatigue-sensitive details in steel structures and engineered components. Our analysis-oriented workflow helps project teams document assumptions, evaluate fatigue demand and coordinate engineering review.
Purpose & Scope
Understand how repeated loading affects service life
Fatigue damage can accumulate when a structural component experiences repeated or fluctuating stress, even where individual cycles do not cause immediate failure. Relevant applications may include cyclically loaded steelwork, equipment supports, brackets, welded attachments, and other components subject to repeated operational loading.
Fatigue analysis requires more than identifying maximum stress. The load history, stress amplitude, number of cycles, detail category, material behavior, residual stresses, environmental exposure and applicable design standard may all affect the assessment.
Engineering accountability: Method selection, design-code applicability, acceptance criteria, safety decisions and final approval must be established and reviewed by the project’s authorized engineering professionals. No fatigue life or compliance outcome can be promised without project data and analysis.
Technical Coverage
Fatigue-life assessment methods
Stress-life (S–N) assessment
Review stress ranges and cycle counts against fatigue-strength data or detail categories where an S–N method is appropriate. This is commonly relevant to high-cycle applications and code-based welded-detail assessments.
Strain-life (ε–N) assessment
Consider local cyclic strain behavior where plastic strain is relevant and the loading regime calls for a strain-based approach.
Crack-growth evaluation
Where justified by available crack data, material properties and inspection assumptions, review crack propagation using an applicable fracture-mechanics method.
Finite element stress review
Use structural or component models to locate fatigue-sensitive regions and examine stress responses under defined load cases. Mesh sensitivity, stress extraction location and boundary-condition assumptions require engineering scrutiny.
Variable-amplitude loading
Where time-history data is available, load-cycle counting (including rainflow methods where applicable) may support fatigue demand evaluation. Damage accumulation assumptions should be explicitly documented.
Durability and design coordination
Communicate findings and potential detail changes for engineering evaluation, without treating a proposed modification as approved or verified until it has passed the necessary review.
Information Required
Project inputs that shape a reliable assessment
- Geometry, component drawings, connection details and available 3D models
- Material grade, relevant properties and weld or connection specifications
- Static, cyclic or time-history loads and expected operating cycles
- Boundary conditions, restraints, load paths and service environment
- Required standards, design life and client-defined acceptance criteria
- Available inspection, service history or existing-crack information
- Prior FEA results, test data, measurement records and assumptions
- Requested deliverables, review milestones and document formats
Working Method
From source information to review-ready findings
Evaluate inputs
Organize geometry, material assumptions, loading cycles and available models.
Assess response
Develop or review stresses and fatigue calculations using the agreed method.
Document review
Issue traceable findings, limitations and items requiring engineering disposition.
Typical Deliverables
Technical documentation for engineering review
Analysis basis and input register
Loading assumptions, material references, model versions, applicable criteria and identified gaps.
Stress and fatigue summaries
Selected stress-range results, fatigue calculations, cycle assessments and method limitations where included in scope.
Review notes and revision records
Traceable observations, outstanding engineering questions and documentation of approved changes.
Project Fit
Applications requiring careful coordination
- Welded steel connections and attachments
- Industrial platforms, frames and equipment supports
- Repeating-load brackets, components and assemblies
- Machinery or operationally loaded support structures
- Existing components with inspection or service-history concerns
The exact scope—analysis, modeling, calculation support, reporting or drawing revisions—should be agreed before work begins. Independent testing and certification are not implied.
Frequently Asked Questions
Questions about fatigue analysis
How is fatigue analysis different from static stress analysis?
Static analysis evaluates structural response under specified loads. Fatigue assessment additionally considers repeated stress variation and cycle exposure over time.
Do you need a complete loading history?
Preferably the loading information should represent service conditions. Where data is incomplete, assumptions and limitations must be agreed with the authorized engineer before drawing conclusions.
Can fatigue analysis use an existing FEA model?
Potentially, subject to review of its geometry, mesh, materials, boundary conditions, load cases and suitability for fatigue stress evaluation.
Does a calculated fatigue life guarantee safe operation?
No. Results depend on the analysis method, supplied inputs, uncertainties and design criteria. Final engineering acceptance and any inspection or maintenance requirements remain with responsible professionals.
Discuss your fatigue analysis requirements
Share your component drawings, loading information and required analysis scope for an initial project discussion.