How to Model Bonded Joints

Purpose

The Computational Structural Mechanics Working Group (CSM-WG) wishes to commission a new document with the suggested title “How to Model Bonded Joints”. The book will form part of the existing “How to...” series of NAFEMS documents.

The successful How To series of publications is designed to guide both new and experienced analysts. The booklets are written to introduce various analysis methodologies to engineers and engineering managers, in a straightforward and informative manner.

Joints are an essential part of products in all sectors of industry, Civil and Offshore, Power and Pressure, Aerospace and Land Transport, Consumer Goods and Biomechanical applications. Joints are important not only with respect to structural integrity and performance of the products themselves but in the jigs, fixtures and test hardware used throughout the product manufacture and qualification process.  

Components are assembled together to maintain structural integrity and performance using a variety of methods either temporary allowing for repeated disassembly and reassembly necessary for maintenance activities or permanent attachment. Mechanically Fastened Joints, bolted and riveted are considered inherently different to bonded joints and is subject of a separate publication.  

Bonded joints are considered permanent as an integral part of the product assembly.  To maintain performance the joints need to survive all the loading environments experienced during the manufacture, assembly and testing and to deliver the required product performance throughout the in service life. The loads can be steady state or cyclic from vibration, shock and thermal environments.

Intended Readership

The document should be applicable to those familiar with or involved in design and engineering analysis and wish to learn about this subject area of simulation technology. The document should also be of value to Project Managers over seeing the use of these analyses. It should be assumed that the design engineers and analysts are familiar with basic Finite Element theory.

Booklet outline

(It should be noted that the outline provided below is that suggested by the CSM-WG but the prospective author may suggest changes based on their own experience.)

• Identification of the configuration of bonded joints covered in the document, scarf, single step  single lap, multiple step single lap, single step double lap and multiple step double lap joints for example.

• The loading conditions considered, mechanical and thermo elastic and modes of failure, shear or peel for example.  

• Introduction of the key features and mechanism of load transfer of the various types of joint.  

• Introduction of the key parameters important to the performance of the joints, adherend stffiness, thickness of bond and adhesive material characteristics for example.

• Identification of modes of failure and assessment criteria using established sources of references where available and appropriate.  

• Identify the significance of preload and/or pre-stress inherent in the joint and how to account for it in assessment of joint performance.

• Examples of idealisation of various types of joint to represent joint stiffness characteristics in larger assemblies of products.

• Examples of idealisation of various types of joint for detail analysis at component level.

Guidance for proposal

Each proposal should consist of;

1.    The proposed structure of the book with the titles of the examples to be developed

2.    The proposed source of the data to be published

3.    Work plan including milestones and interim deliveries for early review

4.    Cost

5.    The authors’ credentials, curriculum vitae, etc. Proposals from single authors and consortiums will be considered.

Typical “ How to…” documents are 60-100 pages long and the cost of preparing the document is expected to be in the low thousands of pounds.

All proposal should be sent to NAFEMS at csmwg@nafems.org to arrive no later than 31st October 2013.

Further details are available from the NAFEMS office or by contacting the Chairman of the CSM-WG csmwg@nafems.org.