Aluminium honeycomb is a light weight, thin-walled material with a typical multi-cellular construction and a good strength-to-weight ratio. Therefore, aluminium honeycomb can be used as an energy-absorbing device for high-speed trains. Due to its large mass and high operating speed, a high-speed train can generate large impact energy. Thus, an energy-absorbing device with a greater energy absorption capability must be designed for high-speed trains. To reduce the aerodynamic drag, the cross-sectional area of a high-speed train is limited. Therefore, a honeycomb energy-absorbing device should be designed in such a way that it is longer than the traditional energy-absorbing devices; however, this may lead to bending, destruction and uncontrollable deformation of the honeycomb; these factors are not conducive for energy absorption. In this paper, a sleeve structure was designed for high-speed trains, and a crash experiment of the energy-absorbing structure showed that the bending and destruction of the honeycomb energy-absorbing device are effectively suppressed compared with the ordinary honeycomb energy-absorbing structure. Moreover, the fluctuation of the crash force was smaller and the crash force is more stable than the traditional thin-walled energy-absorbing structure. Therefore, the deformation instability problem of the ordinary honeycomb energy-absorbing structure and the crash force fluctuation problem of the traditional thin-walled energy-absorbing structure can be solved. Then, a crash experiment and simulation involving a high-speed train with improved honeycomb energy-absorbing device was carried out, and the results showed that the deformation of the end of the train body was stable and controllable, and the train body deceleration satisfied the collision standard EN15227.

Cold recycled asphalt mixture (CRAM) has been reported to be able to provide a cleaner method to rehabilitate damaged asphalt pavement. This work used the CRAM containing emulsified asphalt (AE) and cement to investigate the methods of improving its early-age strength by considering mixture composition, including the types of AE and cement and the contents of AE, cement, and moisture. The curing conditions, such as temperature and humidity, were also involved. The results show that the mixture should be carefully designed to determine optimum AE and moisture content. Also, high cement content was helpful to increase the early-age strength. By changing the curing environment, it was found that raising curing temperature and applying a relatively low humidity contributed to the early-age strength improvement. The interaction of cement hydration and AE demulsification was investigated using microimage and laboratory experiments. The results show that AE particles were easy to cluster because of the negative ions released by cement hydration. AE delayed the early cement hydration but improved the later intensity of cement hydration. The coupling effect of AE and cement resulted in higher early-age strength than those of the mixtures only with cement or only with AE. The results presented in this work are expected to give guidance for preparing a CRAM with high early-age strength.

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On the premise of ensuring the structural strength and safety performance of escalator truss, in order to improve the efficiency of design and development of serial escalator truss, a parametric finite element analysis platform for escalator truss is developed by using the secondary development of finite element method and Visual C++ and data interface technology. In this paper, the structural design and strength characteristics of escalator truss with different parameters are studied, and the strength characteristics of escalator truss with maximum boundary load are analysed. The results show that by using the parameterized finite element analysis platform of escalator, users can get the structural strength results of the serialized truss through automatic modelling calculation only by inputting parameters. While satisfying the structural strength of the truss, the analysis process is greatly simplified and the analysis efficiency is improved.