The proposal aims to investigate the influence of welding process on deformation and fracture behaviour of S355ML steel, which is of the type used for offshore renewable energy monopile structures. Internal stresses are known to have significant effects on material’s mechanical properties, fatigue and fracture behaviour. Therefore to understand the evolution of intergranular stresses under tensile and compressive loading conditions, it is proposed to perform neutron diffraction measurements in-situ on loading of cross-weld test pieces at room temperature. The results from this experiment will be used to account for the role of residual stresses on deformation, fatigue and fracture behaviour of thick-walled monopile foundations and will help to improve the design of offshore wind monopile structures.