This work focuses on the effect of strain rate and fibre rotation on the in-plane shear properties of composite laminates. The effect of fibre rotation on the measured shear properties, was for the first time experimentally quantified with the comparison between compression and tension tests of the ±45° laminate samples. Significant increase of shear strength and decrease of final failure strain was observed with the increase in strain rate from 5e-4 1/s to 1300 1/s. The nonlinear constitutive model was developed to simulate the large deformation process, in which the fibre orientation was updated as a function of the in-plane shear strain. The results of this investigation should motivate the updating of procedures for experimental characterization as well as analytical and numerical modelling of in-plane shear response of laminates.

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Longitudinal compression testing of unidirectional FRP laminates remains a challenge due to the difficulty in applying high compressive loads without stress concentrations and boundary effects leading to premature failure. This work aims to critically evaluate different specimen designs and laminate configurations, cross-ply in particular, for the determination of longitudinal compression properties of unidirectional plies. To this end, a comprehensive experimental campaign has been carried out, comparing strength, stiffness, and failure modes across different specimen designs and laminate configurations. The investigated cross-ply specimens produced comparable results without many of the issues observed in the testing unidirectional material and, therefore, are strongly recommended for the determination of longitudinal compressive strength. Finally, the cross-ply material was tested under off-axis compression to study the effects of shear on the longitudinal compression strength using a series of compression specimens cut at different angles between 0 and 15° to the direction of the laminate.

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This paper describes novel experiments to identify the reduction in compressive strength of crosslaminated timber (CLT) at elevated temperatures. The adhesive type and number of timber plies was varied between CLT samples to allow an assessment of the CLT 'system', rather than timber only. Samples were subjected to steady state and transient heating conditions and their ultimate load bearing capacities were measured. At ambient reference temperatures, a statistically significant difference in ultimate compressive strength was observed between ply numbers but not between adhesive types. For transiently heated samples, capacity was reduced at 100 °C for CLT bonded with polyurethane adhesive type as compared to samples bonded with melamine formaldehyde. The presented results indicate that the composition of CLT can influence the whole system structural response, both at ambient temperature and under fire conditions.

9Plate impact tests on IM7/8552 composite laminates with different projectile 10 incident angles and velocities were carried out. Numerical simulations were conducted to 11 predict the impact damage, with both Puck and LaRC failure criteria having been employed in 12 this study. The dynamic failure performance of IM7/8552 lamina was reviewed first, by 13 referring to data obtained from experiments conducted at a range of strain rates. The 14 performance of the assessed modelling approaches was evaluated by comparing the results 15 of simulations against experimentally (quantitatively and qualitatively) acquired projectile 16 velocity, impact load and the failure modes of the plates. It proved to be challenging to model 17 1