Underwater structures are subjected to hydrostatic pressure during their service life. Sharp V-notched components can be seen as a part of many underwater structures. For example, welded components, machined parts, gears, screws and bolts are among the well-known elements that contain sharp V-notches. The notch tip is a likely zone for initiation of cracks due to high stress/ strain concentration. The reliability analysis of the V-notched components requires a good understanding of stress/ strain distribution near the notch tip. The fracture initiation of the V-notched components can be controlled by the tangential strain field near the notch tip. The tangential strain distribution and fracture initiation conditions are studied in this paper for notched components subjected to hydrostatic pressure. The effect of each tangential strain term on fracture initiation angle as well as tangential strain distribution around the notch tip is investigated using finite element simulation of a V-notched semi-circular specimen. It is shown that not only the singular terms, but also the “constants train field” significantly influence on tangential strain distribution and fracture initiation angle around the notch tip. The results of this paper can be used for standardization of the fracture in underwater structures containing V-notched components.

This paper presents an analytical and a numerical thermomechanical investigation of a thick-walled cylinder made of the functionally graded materials (FGMs). The hollow cylinder is subjected to a pressure and a thermal load and the properties of this material are varying across the thickness from the inner face that is a ceramic to the outer one which is a metal. After validating the current results by the analytical results, the thermomechanical behavior of the cylinder in the transient condition is investigated and the hoop and radial stresses and also temperature distribution are reported. The results reveal that the use of FG material causes a decrease in the stress; thus, it significantly improves thermomechanical behavior of the domain, thanks to using FG materials.