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Aiming at the bending performance of the prestressed superposing-poured concrete beam, the numerical simulation on the composite beams poured with the normal weight concrete (NWC) superposed on the fibred ceramsite lightweight aggregate concrete (LWAC) was conducted. Three kinds of prestressing schemes, straight linear prestressing force, curved prestressing force not across the casting interface, and curved prestressing force across the casting interface, were simulated for comparison, and the influence of the casting interval time was also considered. Results indicate that the stiffness of the superposing-poured beam can be effectively strengthened by considered schemes of the prestressing force; in addition, there are certain increases on the ultimate load except imposing the straight linear prestressing force. As the curved prestressing force is imposed across the casting interface, the maximal interlayer slip of the casting interfacial transition zone (C-ITZ) approximately equals to that without the prestressing force. The scalar stiffness degradation (SDEG) of the C-ITZ for the casting interval time being 14 days is obvious because of the weakening on the bonding performance of the C-ITZ. Comparatively, the SDEG variation of the C-ITZ in the model with the curved prestressing force across the casting interface is smoother and smaller on the whole than the other two prestressed schemes for the case of the casting interval time being 14 days.

This paper starts with the main components and influencing factors of complex skills. Combined with the characteristics of desktop virtual reality system, this research proposes the particularity of complex skills training in the virtual reality environment. In terms of its particularity, it designs a teaching system for complex skills training based on desktop virtual reality system. Finally, according to different learning conditions and combined with the study of learning theory, this paper puts forward the teaching strategies and methods of the teaching system of complex skills training in the virtual reality environment.

Aiming at the bonding performance of the casting interface in the composite ceramsite lightweight aggregate concrete (LWAC) and normal weight concrete (NWC), the experiment on the shear bonding blocks and bending composite beams were designed for progressive study. The Z-shaped composite blocks were first made by the LWAC and NWC with different strength grades considering the variation of the casting interval time and the interface preparing method. The bending composite beams were designed considering the variation of the casting interval time, the relative position between the casting interface and the calculated sectional neutral axis in the LWAC and NWC composite beam. The result indicates that, the bonding shear performance of the casting interface decreases most obviously within 2 days of the casting interval time. The shear strength of the casting interface with 14 days casting interval time for considered different interface preparing methods is higher than that calculated according to the specification. Although there is no bonding sliding failure happening on the casting interface in the composite beam during the experimental loading, a certain influence exists on the crack developing near the casting interface, the load-deflection curve developing, the strain developing of the mid-span section and the subtle damage variation considering the variation of the casting interval time, the relative position between the casting interface and the calculated neutral axis in the composite beam.