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This paper proposes a vortex-induced vibration (VIV) reliability analysis method based on the maximum entropy (MaxEnt) principle in which constraints are specified in terms of fractional moments involving uncertain wind characteristics, structural properties, and bluff-body aerodynamics. The multiplicative dimensional reduction method (M-DRM) is used to calculate the fractional moments. A new threshold is obtained based on the stopping sight distance in the highway engineering technique standard, which is less strict than the China–Japan standard and the British code and thus better-suited to VIV reliability evaluation. A long-span cable-stayed bridge model is used to illustrate the accuracy and efficiency of the proposed method in comparison to Monte Carlo simulation (MCS) on three performance functions of VIV reliability. The results indicate that VIV maximum amplitude and wind speed failure probability are not sensitive to the selected performance function, but the effect of the wind attack angle on probability is significant. The M-DRM provides a workable alternative approach to analyzing the highly complex VIV reliability of long-span bridges. [ABSTRACT FROM AUTHOR]

Rutting has been one of the primary concerns for highway engineers in China. Granulated polymer anti-rutting additive may be an effective way to solve this problem. However, it is difficult to find previous research on the application of granulated polymer as an anti-rutting additive in different types of asphalt mixtures. This research aims to investigate the influences of the anti-rutting additive contents on road performances based on different types of asphalt mixtures, and also explores potential reasons for road performance improvement. Three types of asphalt mixtures: dense-graded asphalt concrete (DG-AC), dense-graded Superpave (DG-Superpave)，semi-open-graded asphalt macadam (SOG-AM), were included. Road performances, including high-temperature performance, low-temperature performance and moisture susceptibility, were studied at three anti-rutting additive percentages: 0.2, 0.3 and 0.4% weight of the asphalt mixture. The mixtures without the anti-rutting additive were regarded as control groups. In order to better analyse the road performance improvements, the properties of modified asphalt with 0.4% anti-rutting additive were studied, as well as the anti-rutting additive physical form in the asphalt mixture. It was found that the anti-rutting additive improved mixture's high-temperature performance significantly while its effects on low-temperature performance were not so. It reduced low-temperature tensile strain within 12.9% range. Moisture susceptibility was improved greatly after adding 0.2% anti-rutting additive as compared to the corresponding control groups. By increasing the additive contents to 0.3 and 0.4%, the moisture susceptibility had no significant difference compared with that of the 0.2% additive content group. Road performance improvements may relate to the combined action of reinforcement and gap filling by the elongated anti-rutting additive, as well as asphalt modification within short time. When the additive content is no more than 0.3%, the materials costs of the additive-modified asphalt mixtures are less than that of SBS-modified asphalt mixtures. [ABSTRACT FROM AUTHOR]

Evaluation indices were proposed and rated based on statistical analysis of collapse by an improved backward cloud algorithm considering internal and trigger factors. The evaluation index weight was calculated by a G1 method. A hazard evaluation of a highway collapse in China was established on the basis of a spatial analysis function of ArcGIS 10.2 and a factor superposition method. A hazard zoning of highway collapse in China was also performed based on the hazard degree. Results show that a comprehensive hazard index of highway collapse hazard in China based on the evaluation index above ranges from 1.0 to 9.0; and the distribution law of the collapse along a highway coincides with the actual distribution of highway collapse hazard. The most dangerous zones are the mountainous area of Southeast Taiwan, the mountainous area of Southeast Fujian–Zhejiang, south of Hainan, Sichuan–Yunnan mountainous area, Tianshan Mountains and Kunlun Mountains. The results can provide a reference for highway collapse prevention and mitigation work. Abbreviations: AHP: Analytic Hierarchy Process; GIS: Geographic Information System [ABSTRACT FROM AUTHOR]