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To improve the mechanical performance of specially shaped reinforced concrete columns, which are widely applied in China, an innovative specially shaped composite column with high-strength concrete-filled steel tubular core was developed. To investigate the fire performance of this specially shaped composite column, two series of fire tests, including the fire resistance test series and the postfire test series, were conducted on five full-scale specimens. The test parameters include the axial load level, the spacing of stirrups, and the fire exposure time. Compared to the test result of a controlled specimen that was axially compressed to fail without exposure to any fire, both the fire resistance under fire and the residual capacity after fire of this specially shaped composite column were analyzed and studied. The results indicated that the inner concrete-filled steel tubular core plays an important role in both the fire resistance and the post-fire performance, and that the post-fire residual capacities of three post-fire testing specimens were also largely increased.

A series of HPA-containing Poly(phthalazinone ether ketone) (PPEK) membranes was prepared and their microstructure and conductivities were studied in this work. The results showed the composite membrane had no proton conducting ability with PWA content less than 75%, while the conductivity for the PWA/(PEEK-PVP) membranes with 35% of PWA was higher than 4×10-4 S/cm. Proton conductivities up to 4.86×10-3 S/cm have been measured at temperatures up to at 140°Cand 100% RH for PWA/(PEEK-PVP) membranes with 35% of PWA and 70% PVP. The relationship of conductivity and the morphology of the PPEK/PWA membranes showed that the PWA particle dispersion is the key parameters.