a b s t r a c tAccuracy of the gas permeability parameters (GPPs), i.e. solubility, diffusivity and permeability deduced from permeation measurements, is investigated for the case of homogeneous polymer sheet samples. The widely used time-lag method (TLM) and the recently introduced full curve-fitting method (FCFM) are compared on simulated and on measured permeation curves artificially distorted in various ways in order to mimic potential deficiencies of permeation measurements. Accuracy of the methods is defined as the relative deviation of the calculated from the real GPPs, i.e. those which are deduced from the distorted and the original, non-distorted curves, respectively. The following distortions have been applied: temporal truncation of the permeation curves, increasing the noise level of the measurement and shifting the permeation curve either along the concentration or the time axis. (The latter two transformations correspond to an unnoticed background shift in the readings of the concentration detection unit and an uncertainty in the actual inception of the permeation process, respectively). While all these distortions mimic realistic deficiencies of permeation measurements, the last one is relevant only in case of fast permeation processes through highly permeable membranes. For all but the last transformation, FCFM has been found to yield more accurate GPPs than TLM.

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It is reported on rigid moment and shear force resistant connections of glulam to concrete or steel abutments based on glued-in steel rods. The connections are especially meant for clamped columns and integral bridge decks and wide-span end-clamped floors. In order to prevent premature splitting failure of the joint and to enforce a rather even shear force distribution on spaced rods the issue of lateral joint reinforcement by self-tapping screws or/and gluedon plywood panels is emphasized. The proposed design equations are calibrated by results of an extensive experimental campaign, revealing that the new Eurocode EC5-1-1 is overly conservative regarding lateral forces and respective normal force interaction. It is revealed case study-wise that the investigated rigid joint configurations present superior rotational stiffness and load capacities vs. today´s primarily employed mechanical fastener solutions with slotted-in steel plates or grout embedment of the GLT column in bucket foundations. The study demonstrates a technically competitive and environmentally advantageous timber solution vs. precast concrete columns. It offers new options for hybrid timberconcrete applications for timber bridge decks and clamped wide-span floors.KEYWORDS: rigid glulam connections, moment and shear force resistant joints vs. concrete abutments, lateral joint reinforcement, self-tapping screws, glued-on plywood panels, clamped columns, bridge decks and floors, hybrid timberconcrete joints

In thermal depth profiling of fibre-reinforced materials, the thermal and the optical properties were determined separately and with low relative errors. This is mainly due to the fact that the thermal and optical properties of the measured samples affect the measured photothermal phase at different modulation frequencies corresponding to different characteristic length of the thermal diffusion and optical absorption. The error limits of the thermal and optical parameters are determined by the root-mean-sqare deviations of the measured phases and by the error of the measurement of the static sample temperature.