Composite Test Rig Design & Analysis
Load Testing a Bespoke Composite Component
Load Test Rig Analysis and Design
A test rig was required for extreme static loading up to 4.5MN and fatigue loads of up to 3MN (R=0.5) for a composite box section component. Two components were to be tested, one to static failure and the other to fatigue failure (or cycle limit). Testing machines to provide this level of load are not generally commercially available, so Blackfish designed and analysed a bespoke test rig for the purpose. In order to keep the costs down, the final design utilised existing hydraulic rams and a fabricated load frame using standard steel section that could be easily transported to site and assembled in situ. The rig had capability for automated hydraulic control for 24/7 operation, in order to achieve the required fatigue cycles within an acceptable timeframe. Control, data logging and safety system cut-out capability was also included as part of the design.
Key elements of the work included
- Design concept idea generation and concept selection
- Hand calculations of stresses under extreme loads to provide basic size guideline
- FE analysis of extreme and fatigue loads to assess rig integrity, using ANSYS Mechanical, especially in areas of welds.
- CAD design and detailed manufacturing drawings of the 10.5te structure
- Definition of instrumentation to be used for testing, including strain gauges, load cells and video as well as various composite inspection techniques
- Delivery of test plan, risk assessment, data analysis plan and fully costed programme of work to assess component to failure.
- Definition of control and actuation hardware requirements, including data logging, hydraulic cylinder cyclic loading and instrumentation to provide safety system automatic cut out.