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A series of innovative connections with the different combinations of steel plates and screws was developed for timber–concrete composite (TCC) system in this paper. Several groups have introduced vulcanized rubber layer to the jointing steel plate, which was used to be glued onto the timber beam surface. Push-out tests were carried out on the proposed connections and three replicates were prepared for each series. The study focused on the load carrying capacity, slip modulus, ductility and the role of some factors of the innovative connections. Moreover, the load-slip behaviour was evaluated based on an existing non-linear model and parametric analysis was also conducted. The research results showed that this connecting system looks suitable for structural application.

Few-layer vertical graphene (VG) was prepared on arrayed carbon nanotubes (CNTs) without a catalyst by using radio frequency sputtering deposition and microwave plasma enhanced chemical vapor deposition, and the field emission (FE) performance of VG–CNT composites was tested and optimized. The FE performance is found to be strongly dependent on the heights (but not the actual heights) and densities of CNTs, the shapes of VG, and the diameters of VG–CNT composites. The optimal shapes for FE are demonstrated to be CNTs with middle densities and small diameters and VG with high densities and small sizes. The optimal FE performance from our large area VG–CNT composites is found to have a low threshold field of 1.28 V/μm (at 10 mA/cm2), a high maximum emission current density of 87.63 mA/cm2 (4.28 times higher than that from our previously prepared graphene–CNT composites), and excellent stability at an extremely high mean emission current density of 36.28 mA/cm2 over a period of 50 h, far better than those of pristine CNTs, pure VG, and shape non-optimized VG–CNT composites.

This paper presents a summary of the experimental programmes and theoretical analysis of the bending performance of non-prestressed and prestressed timber-concrete composite (TCC) beams. Two non-prestressed and three prestressed composite beams were selected, and their flexural behaviour was evaluated. Three types of ductile fabricated connections were applied to the prestressed composite beams, whereas two types were applied to the non-prestressed beams. The concrete slabs with embedded steel plates and timber beams were connected together using coach screws. On the surfaces of the embedded steel plates, the portions in contact with the wooden beam were interspaced with a vulcanized rubber layer to improve the mechanical performance of shear connections and composite beams. A series of four-point bending experiments were performed until collapse failure occurred in a simply-supported scheme. The test results demonstrated that the TCC beams using steel plate + screw connections exhibited excellent structural performance. The flexural capacity of the prestressed specimens was improved by approximately 110% compared with the non-prestressed specimens. Due to the addition of the rubber layer in the TCC connections, the flexural capacity of the prestressed composite beams was improved by 25.2%. Based on the ‘γ–method’, a theoretical analysis was proposed for calculating the flexural capacity and bending stiffness for both non-prestressed and prestressed TCC beams. The theoretical results showed good agreement with the experimental evidence.