Geometrically non-Linear Thermal Stress Analysis of an Adhesively Bonded Tee Joint With Double Support

Abstract

In this chapter, the geometrically nonlinear thermal stress analysis of an adhesively bonded tee joint with double support is carried out using the finite element method. The tee joint is also bonded to a flexible horizontal plate, and it is subjected to variable thermal boundary conditions—that is, air flows with different temperature and velocity parallel and perpendicular to outer surfaces of the tee joint. First, the heat transfer analysis of the tee joint is carried out to determine the temperature distribution through the joint members. Considerable heat fluxes are observed in the adhesive fillets at the adhesive free ends, whereas uniform temperature distributions occur in the vertical and horizontal plates and supports. Later, the geometrically nonlinear stress analysis of the tee joint is carried out considering large displacement and rotation effects. The stress analysis of the tee joint is repeated for two boundary conditions in which the edges of horizontal and vertical plates are fully fixed and partially restrained. In both cases considerable stress concentrations occur in the adhesive fillets around the adhesive free ends. The horizontal and vertical plates experience serious stresses along outer surfaces. However, the most serious stresses are observed in case the edges of the horizontal and vertical plates are fully fixed. The effect of support length on the peak thermal stresses is investigated, and an optimum support length is determined based on the peak thermal stresses in the adhesive and plates. Finally, the adhesive joints with simple or complex geometry may experience thermal strains resulting in serious thermal stresses under thermal loads due to thermal and mechanical mismatch. In addition, even a simple mechanical boundary condition may make these thermal stresses serious. Therefore, thermal boundary conditions should be taken into account in the design of the adhesively bonded steel joints.