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This report documents the fabrication and test of a woven glass/epoxy composite laminate that was reinforced in the through-thickness direction with aramid fibers using a needling process. The purpose of reinforcing laminated material in the through-thickness direction is to improve its delamination resistance/damage tolerance. The needled material was approximately 6.4-mm thick and was tested using American Standard Test Method ASTM standards to assess the improvements in impact response and any reductions in-plane strength, which is a typical tradeoff with 3D-reinforced stitched materials. Needled specimens exhibited 10-15% increase in effective stiffness (force-deflection response) under impact loading, and a 50% increase in compression-after-impact strength-a significant improvement in damage tolerance. Needled but non-impacted material exhibited a 9% increase in the in-plane compressive strength and a 17% increase in flexural strength, indicating at least that the needling process does not cause immediate tradeoffs in the in-plane strength of woven glass materials. Because the processing parameters were arbitrarily chosen, these experiments should be considered as proof-of-concept.

A procedure for the rapid and accurate mapping of the depth to the texture contrast horizon of duplex soils was trialled. Data were collected using ground-penetrating radar with a 250 MHz antenna at 4 sites in the Esperance region of Western Australia. The contrast at the B horizon was identified using a ‘picking’ process similar to seismic surveys. The GPS data were integrated and depth to B horizon maps produced by kriging. The results were related to core data taken for sites and showed that GPR can provide accurate and detailed subsurface maps with ±0.1 m accuracy for B horizon depth. The influence of B horizon material composition on GPR response was also investigated using amplitude mapping. The spacing between GPR transects can affect map quality, particularly if the lateral variation in the B horizon depth is not adequately sampled by the line spacing selected. With further integration of the data collection and post-processing procedures, this would prove to be a useful tool for farmers and natural resource managers.