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Night-time vehicle accidents under low illumination conditions are frequent and serious, and they have attracted widespread attention. The objective of this study was to explore how various factors affect night-time vehicle accidents using data collected from a city in China. Combined with logistic model theory, the occurrence or absence of a night-time fatal accident was set as the dependent variable. A total of 10 variables, including the accident site, road type and road surface conditions, were selected as independent factors. Based on 2106 valid night-time vehicle accidents, a binomial logistic model was established to evaluate the impact of contributing factors on the severity of these accidents. The results show that the accident site, accident type and presence of a median divider are important factors that affect the severity of night-time vehicle accidents under low illumination conditions. The probability of fatal night-time accidents on road segments is 2.387 times that at intersections. The probabilities of fatal single-vehicle and vehicle-pedestrian night-time accidents are also greater than that of fatal vehicle-vehicle night-time accidents, by factors of 7.591 and 1.749, respectively. The probability of fatal night-time accidents on roads with median dividers is 3.273 times greater than that on roads without median dividers.

The inverted-trapezoid sectioned dovetail (ITSD) mortise-tenon joint was popular during the Chinese Song Dynasty. To investigate the particular features of the ancient wood joint, three 1:4 scaled models of a double-span timber frame with two exterior joints and an interior joint were fabricated according to the construction method commonly used in Chinese traditional wood structures, and tested subjected to fully reversed cyclic loading. Investigated were the mechanical properties of the ITSD mortise-tenon joints such as the connection stiffness and flexibility, hysteretic model and the relationship between the bending moment and relative rotation (i.e. the M-θ′ model). The constitutive parameters of the Kishi-Chen M-θ′ model for ITSD mortise-tenon joints were calibrated using statistical fitting methods. Besides, an assumption applicable to the connection type (e.g. pinned, semi-rigid or rigid joint) at a given connection bending-moment level was suggested with respect to practical engineering purposes. Furthermore, the M-θ′ model obtained for ITSD mortis-tenon joints was incorporated into the commercial software SAP2000, and the experimental hysteretic curves obtained for the three scaled specimens were compared with the curves obtained using finite element method (FEM), it was found that the M-θ′ model validated by this study was applicable to the ITSD mortise-tenon joint.

A finite cylindrical cavity expansion model for metallic thick targets with finite planar sizes, composed of ideal elastic-plastic materials, with penetration of high-speed long rod is presented by using the unified strength theory. Considering the lateral boundary and mass abrasion of the target, the penetration resistance and depth formulas are proposed, solutions of which are obtained by MATLAB program. Then, a series of different criteria-based analytical solutions are obtained and the ranges of penetration depth of targets with different ratios of target radius to projectile radius (rt/rd) are predicted. Meanwhile, the numerical simulation is performed using the ANSYS/LS-DYNA finite element code to investigate the variations in residual projectile velocity, length, and mass abrasion. It shows that various parameters have influences on the antipenetration performance of the target, such as the strength coefficient b, rt/rd, the shape of the projectile nose, and the impact velocity of the projectile, among which the penetration depth has increased by 18.95% as b = 1 decreases to b = 0 and has increased by 32.28% as rt/rd = 19.88 decreases to rt/rd = 4.9.