The effect of the yield to tensile strength ratio on stress/strain concentrations around holes in high-strength steels

Application of high-strength steels in the maritime and offshore industry is currently limited by rules governing the ratio of the yield to tensile strength (the Y/T ratio). To better understand the physical basis for these rules, the nature and extent of the plastic stress/strain field in the vicinity of a stress concentration (a circular...

The effect of the yield to tensile strength ratio on the stress field in stress/strain concentrations around holes in steel structures

The aim of this thesis is to determine the influence of the Y/T, yield to tensile strength, ratio on the stress fields of high strength steels. This is relevant to the offshore industry as regulations restrict the use of steels with a high yield to tensile strength ratio, which is a characteristic of high­-strength and<br/>ultra high­-strength...

Feasibility of locally-coupled elasto-plastic damage modeling for remaining life prediction of low-speed damaged roller bearings under heavy loading condition

Low-speed roller bearings are generally in the sheave bearings and turret bearings which are used in the offshore industry under heavy loads. One of the challenges to the integrity of these bearings is the presence of subsurface cracking in the raceways. Downtime cost, which is caused by the failure of<br/>these bearings is significant. Based on...

Replicating cohesive and stress-history-dependent behavior of bulk solids: Feasibility and definiteness in DEM calibration procedure

This paper presents a multi-step DEM calibration procedure for cohesive solid materials, incorporating feasibility in finding a non-empty solution space and definiteness in capturing bulk responses independently of calibration targets. Our procedure follows four steps: (I) feasibility; (II) screening of DEM variables; (III) surrogate modeling...

Micro fracture investigations of white etching layers

The fracture behavior of a white etching layer formed on the rail surface in pearlitic steels during the rail-wheel contact is investigated using indentation-based microcantilever fracture tests. The sample thickness is in the order of 5 μm. The local fracture toughness of the white etching layer, its neighboring brown etching layer, martensite...

Numerical Research on Elasto-Plastic Response of FPSO Topside Modules Subjected to Blast Loading Aiming at a Simplified Design Method

Structural blast analysis is usually done with two load levels for different design stages; the Strength Level Blast, SLB, and the Ductility Level Blast, DLB. Strength Level Blast is the lower magnitude overpressure (with a higher frequency of occurrence and lower consequence) and Ductility Level Blast is the higher magnitude overpressure (with...

Large Strain Analysis of Electro-Osmosis Consolidation for Clays

Consolidation of soft clay creates a lot of problems in foundation engineering, because of the very low clay permeability and high compressibility. Primary consolidation takes a long time to complete if the material is left consolidating under atmospheric evaporation, and traditional dewatering techniques, such as surcharge preloading, vacuum...

Numerical simulation of elasto-plastic electro-osmosis consolidation at large strain

n this paper, a numerical solution for the electro-osmosis consolidation of clay in multi-dimensional domains at large strains is presented, with the coupling of the soil mechanical behaviour, pore water transport and electrical fields being considered. In particular, the Modified Cam Clay model is employed to describe the elasto-plastic...

FEM modelling of elastoplastic stress and strain field in centre-cracked plate