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In recent years, composite materials have been more widely used in sandwich structures, which have been proved better performance in sandwich structures than other materials in some cases. In this paper, an analytical model is developed to predict the key stress, failure modes, and failure loads of the composite corrugated-core sandwich structures under three-point bending in both longitudinal and transverse directions. Then a three-dimensional finite element model by using Hashin’s model to predict fiber composite laminates and cohesive zone model to predict extra epoxy layer of fiber composite laminates is developed and validated by the corresponding experiments. The analytical model is also validated through both simulation and experiment. Finally, the failure mechanism maps and effects of orientation angles on failure have been further studied based on the analytical model.

This paper presents an analytical, numerical, and experimental study on the failure behavior of single hat-shaped T-joints made of plain woven carbon fiber polymer (T300/epoxy 618) and subjected to out-of-plane bending. The T-joint is manufactured by vacuum bag molding process at room temperature. An analytical model is developed to analyze the experimental results and to establish the associated failure criteria. Two failure modes: (a) laminate buckling and (b) laminate crushing are considered, and the theoretical relationships for predicting the failure load associated with each of the two modes were developed. The experimental data correlate closely with the analytically predicted behavior, including failure mode and bending stiffness. In particular, both laminate buckling and laminate crushing are observed during the experiment with laminate crushing being the final failure mode, which can be considered to be the most important failure mode of the fabricated T-joint. In addition, numerical simulations based on the finite element method and the Hashin damage criteria also accurately predict the flexural modulus, the peak load, and failure locations of the T-joint obtained in the test.

The electric vehicle is seen as an effective way to alleviate the current energy crisis and environmental problems. However, the lack of supporting charging facilities is still a bottleneck in the development of electric vehicles in the Chinese market. In this paper, the cloud model is used to first predict drivers’ charging behavior. An optimization model of charging stations is proposed, which is based on waiting time. The target of this optimization model is to minimize the time cost to electric vehicle drivers. We use the SCE-UA algorithm to solve the optimization model. We apply our method to Dalian, China to optimize charging station locations. We also analyze the optimized result with or without behavior prediction, the optimized result of different numbers of electric vehicles, and the optimized result of different cost constraints. The analysis shows the feasibility and advantages of the charging station location optimization method proposed in this paper.

Stress analysis of adhesively bonded joints of sandwich structures is more complex. Only a few research works have studied this subject. The major obstacle is finding the stress distribution at the adhesive layer of sandwich structures under different loading conditions. This paper presents a study on stress distribution at the adhesive joints of the corrugated sandwich structure subjected to three-point bending using the cohesive zone model. Firstly, three cases of sandwich models with different types of glue on both longitudinal and transverse loading directions were calculated using cohesive zone model, and then the corresponding experiments were carried out and compared to prove the FEM results to validate the results through both load–displacement curves and failure deformation modes. Secondly, the cohesive zone model simulation was used to obtain the detailed stress distribution at the bonding joint with the effect of four major geometrical parameters: adhesive layer thickness, corrugated panel thickness, face panel thickness and adhesive joint width. Lastly, the results of stress analysis showed that the stress distribution is not uniform and is highly affected by the bonding joint's geometrical parameters, adhesive layer thickness and adhesive joint width.

This article presents an engineering method based on the collaborative optimization consistency constraint function for selecting shared components in modular platforms; the method allows the operator to minimize the differences in design variables across various models simultaneously. A case study using the body-in-white information on three vehicles serves as an example. Static bending conditions and static torsion conditions are comprehensively considered with the mass and the maximum displacement as the optimization objectives in Isight and Hyperworks (both of which are commercially available software applications commonly used by automotive engineers.) The results suggest that this method can be easily and effectively utilized in the conceptual phase of car design.

With the improvement of people’s living standard, car has become an indispensable means of transportation, and the specialized car service industry is developing rapidly. Therefore, for the car repair stores, it is the core issue to choose suitable location according to the characteristics of car owners and existing competition. This study puts forward a model aiming at the maximum profit rate considering choice preference of car owners, competition, consumption capacity of owners, and capital limit. Then, a genetic algorithm improved in four aspects is proposed to solve the proposed model. Finally, an example and a case study of Dalian expound the application of the proposed models and algorithms in practice. It proved to be effective to China’s national conditions through the analysis of the results.