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This paper investigates the effect of size and complexity of composite structures on the formation of low-velocity impact damage via experimental tests and numerical modelling. The ASTM standard low-velocity impact test and a scaled-up version of the test were conducted. A novel numerical technique is presented that combines 3D solid and thin 2D shell elements for modelling different domains to achieve a high level of fidelity locally under the impact location, whilst achieving good computational efficiency for large structures. Together with the experimental studies at the different scales, the predictive capability of the numerical models was systematically validated. This modelling method demonstrated an advanced computational efficiency without compromising predictive accuracy. The models are applied to a case study of low-velocity impact of a large-scale stringer-stiffened panel, showing this modelling approach to be suitable for predicating low-velocity impact damage and structural response of laminated composites over a range of sizes and complexities. [ABSTRACT FROM AUTHOR]

In this paper, the constraint effect caused by a side-groove on creep crack growth behavior in P92 steel was studied using finite element analysis. Creep crack growth simulations were conducted on compact tension specimens for side-grooves with different depths and angles. The simulated outcome indicated that the creep crack growth rate increased as the depth and the angles of the side-grooves in the specimen increased. Next, the profile of the crack front for the different specimens was discussed. The distribution of the average stress triaxiality and the average equivalent stress on the crack front were studied to investigate the mechanical mechanism describing the constraint effect on creep crack growth behavior. Finally, the creep crack growth rate determined from numerical simulation results was determined to be consistent with existing experimental data. [ABSTRACT FROM AUTHOR]