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The frost heave force (FHF) is one of the most important reason of inducing freezing damages of tunnel in seasonal frozen regions. Analyzing the change law of FHF is helpful to design for avoiding freezing damages in the tunnel lining. Field measurement is an approved method used in mechanical analysis of tunnel lining, however, it is difficult to measure the FHF directly, which is changed coupled with the original surrounding rock pressure (OSRP). In this paper, in order to clarifying the change law of the FHF, a new measuring method was presented. The best advantage of this method is that the FHF could be separated from the OSRP by measuring the surrounding rock temperature and the lining pressure at the same time. A lot of field measurement work about the FHF was conducted based on Jichoushan tunnel and the change law of the FHF was analyzed using the presented method. The results can provide preference for the antifreeze design of tunnel in seasonal cold regions.

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Pavement skid resistance is an important guarantee for driving safety. However, it is very difficult to determine the exact friction in a field environment. In order to overcome the limitations of traditional evaluation methods, the effect mechanism of surface 3D (three-dimensional) texture on skid resistance was firstly analyzed. Then the surface 3D texture of pavement was acquired through an improved binocular reconstruction method. Additionally, the relationship between friction coefficient and 3D texture was also analyzed. Subsequently, under the concept of IFI (international friction index) used to harmonize different detection methods of skid resistance, the evaluation model of skid resistance based 3D texture was further established. The results showed that the multiple quadratic multinomial regression model can well describe the relationship between skid resistance and texture indicators. The establishment of an improved evaluation model is simple to operate and implement. It can directly evaluate the skid resistance on pavement surface once the aggregates' type and 3D texture are known. This evaluation model not only overcomes the challenges of friction coefficient with a strong conditional restriction, but also provides a harmonious approach for different detection methods in the evaluation of pavement skid resistance.