Structural integrity: designing against failure
Structural integrity is the study of the safe design and assessment of components and structures under load, and has become increasingly important in engineering design. It integrates aspects of stress analysis, materials behaviour and the mechanics of failure into the engineering design process. The module is well-illustrated with case studies, and will be of interest to anyone associated with the design of any component or structure that experiences loading, and will be of benefit in developing skills in the analysis and assessment of product design. It has universal applicability in the UK and across international boundaries.
What you will study
This is an OU level 3 engineering module, which integrates aspects of design, materials selection and mechanical engineering under the banner of ‘structural integrity’. It will be of particular relevance to you if you are studying towards a BEng (Hons) or MEng qualification, or pursuing a BSc and will benefit from exposure to and an understanding of the application of stress analysis principles and the causes underlying materials failures. It is also a valuable updating module for professional engineers as part of your continuing professional development. Structural integrity therefore covers a wide range of skills underpinning the design of products, components and structures that must operate safely and reliably.
The module has two main themes.
The concepts within stress analysis have wide applicability, as there are very few manufactured components and products that do not experience any loading during their life. The module starts with an introduction to the fundamentals of stress analysis, in obtaining stresses from known loads, describing the stress state at a point in a component, and relating stress and strain in a material.
It progresses to looking at loads on structures and assemblies, and methods for analysing these and other loading situations. The concept of residual stress is introduced, and how residual stresses can be introduced during the manufacturing process.
The module then moves on to look at concepts of fracture mechanics. These concepts need to be understood in order to design components that do not fail under their design load, particularly when fatigue loading or environmental effects may have impaired the component’s load-bearing capability. It shows how failure assessment can be used to obtain information as to why a component or structure failed so that better information is available to inform future designs. The material within this section includes the topics below.
- Fracture mechanics begins with an introduction to the study of components that contain flaws or cracks, and how the fracture toughness of materials can be as important as the strength in assessing safety. It then looks at how fatigue of materials occurs, how the fatigue process can be related to fracture mechanics parameters, and how the fatigue life of a component under complex loading can be assessed.
- Failure modes looks at how failures can be analysed to give insight into how a component was loaded and what form of loading or stress state led to failure. It examines how different materials fail according to their fundamental properties.
- Environmental factors; one of the most important factors influencing a material’s lifetime is the environment in which the component will spend its life: for example a factor such as corrosion can have a severe detrimental effect either by initiating or propagating existing flaws.
If you are considering progressing to The engineering project (T452), this is one of the OU level 3 modules on which you could base your project topic. Normally, you should have completed one of these OU level 3 modules (or be currently studying one) before registering for the project module.
You will learn
- How to model the behaviour of engineering structures under load, and use stress analysis principles in problem solving.
- How to model and predict the performance of cracked structures under load.
- To interpret engineering case studies of failure in terms of fundamental fracture mechanics and stress analysis concepts.
This module is part of the BEng (Hons) programme, which can lead to CEng status with a professional engineering institution.
This is an OU level 3 module. OU level 3 modules build on study skills and subject knowledge acquired from studies at OU levels 1 and 2. They are intended only for students who have recent experience of higher education in a related subject, preferably with The Open University.
You should have previously studied engineering-related modules at OU level 1 and 2. You will also need mathematical skills for engineers or scientists. In particular you should be able to:
- describe the concept of stress in an engineering context, and relate it simply to an applied force
- describe the concept of strain, and its relation to stress through the Young’s modulus of a material
- recognise the names of common metals, ceramics and polymers
- distinguish between metals, ceramics and polymers in terms of their atomic and molecular structure, and understand how the atomic-level structure and microstructure of a solid material relates to its physical properties
- identify, from a curve of engineering stress against engineering strain for an elastic material, the Young’s modulus, yield stress and tensile strength of the material
- describe the mechanisms of creep, corrosion and fatigue in materials
- use mathematical principles to solve engineering-based problems.
If you have any doubt about the suitability of the module, please speak to an adviser.
Make sure you are familiar with Windows and suitable word-processing and spreadsheet software.
The module comprises the printed module texts, a DVD-ROM, online forums and a website.
A computing device with a browser and broadband internet access is required for this module. Any modern browser will be suitable for most computer activities. Functionality may be limited on mobile devices.
Any additional software will be provided, or is generally freely available. However, some activities may have more specific requirements. For this reason, you will need to be able to install and run additional software on a device that meets the requirements below.
A desktop or laptop computer with either:
- Windows 7 or higher
- macOS 10.7 or higher
The screen of the device must have a resolution of at least 1024 pixels horizontally and 768 pixels vertically.
To participate in our online-discussion area you will need both a microphone and speakers/headphones.
Our Skills for OU study website has further information including computing skills for study, computer security, acquiring a computer and Microsoft software offers for students.