Electronic Guides
This set of electronic Guides has been developed as part of a DTI Materials Programme. The Guides have been created in pdf format with hyperlinks and are designed to be navigated through on screen. By presenting the information in this format, the reader is able to browse the document and select those aspects of particular interest.
The intention of these guides is to provide designers and users with sufficient information which, when coupled with their own expertise, could for example be used to assess the factors that affect the performance of adhesives and adhesive joints. These guides compliment published works, which provide comprehensive coverage of adhesives technology and preliminary design. For instance NPL Measurement Good Practice Guides provide advice on issues relating to the preparation and testing of bulk adhesives and adhesive joint specimens, acquisition of design data from bulk specimens, finite element modelling of adhesives, flexible adhesives and durability testing.
Calculation of Elastic-Plastic Materials Models Parameters (
PDF 1.03 MB)
This document deals with the determination of properties and parameters required by various elastic-plastic models in FE packages that describe the non-linear mechanical behaviour of tough adhesives. The equations and parameters that form the basis of different models are introduced, and procedures for analysing experimental data to determine model parameters are explained and illustrated. Suitable test methods for obtaining the experimental data are also described. Illustrations are given of stress and strain distributions in the adhesive layer of some common joint geometries that have been calculated using different materials models.
Modelling Creep in Toughened Epoxy Adhesives ( PDF 1 MB)
In order for a stress analyst to confidently design adhesively bonded joints subject to long-term loading, models are needed that describe deformation of the adhesive under creep, intermittent or fatigue loads. The models currently available in finite element packages cannot accurately model the creep behaviour of toughened epoxy adhesives. This document describes the development of an alternative creep model. It explains how the model has been implemented in Abaqus as a user-defined subroutine. The model enables changes in stress and strain distributions in the adhesive of a lap joint to be calculated with time under load. This is demonstrated through FE predictions from a lap joint under creep loading.
Design and Testing of Bonded and Bolted Joints ( PDF 1.51 MB)
This document addresses design and testing issues that affect the strength, stiffness and life expectancy of bonded and bolted joints under quasi-static, cyclic and creep loading conditions. The guide is primarily concerned with metals and fibre-reinforced polymer composites either bonded with structural adhesives (i.e. rubber-toughened epoxies) or bolted. It provides advice on design, testing and manufacture of bonded and bolted structures, and include details of test methods required to generate suitable design data. Factors such as specimen geometry, material properties, processing variables and surface treatments are also considered.