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Combined with practical examples of karst roadbed construction of Zhanghua highway, the article analyzes catastrophic manifestations, disaster causes and common prevention measures of karst collapse caused by roadbed construction; according to research putting forward the corresponding treatment program on engineering examples, engineering practice to good effect, showing that the proposed scheme of karst treatment is reasonable and reliable, referencing for similar projects.

The reasonable speed limit would reduce the detrimental impact on the driving safety and traffic jam in Highway expansion project high slope work zone. The study based on the investigation of Liu Nan highway’s traffic capacity, speed, traffic flow and other related index, which researched the vehicles queuing length of the different lane width in expansion project construction zone. The result is that 1/2 lane occupied need limit speed step by step in the warning area, 1/3 lane occupied limit 60km/h and 1/4 lane occupied limit 80km/h.

The original descriptive model of shear stress and shear displacement only reflects the stress deformation characteristics of plastic structural plane. The index model was revised and piecewise index model was built to describe the stress deformation characteristics of plastic structural plane and brittle structural plane. The relation of stress and strain to the failure mode of structural plane considering the effect of its shape was investigated, and a model which could reflect the relation between undulate angle and shear strength was built. The result indicates that structural plane presents nonlinear characteristics, specifically, the value of undulate angle, as well as corresponding shear strength, becomes larger as the normal stress decreases.

Slope stability analysis requires detect and control the stress and strain timely. Familiar with the slope‘s stress and strain changes in excavation process has important guiding significance for the actual construction. In this paper, choose a slope in Guangxi freeway renovation and expansion process as the research object. Use FLAC3D to analysis the stress and displacement simulation results of this slope excavation step by step. Summarize the excavation regular pattern.

The risk evaluation index system for operation security in high slope construction was drawn up on the basis of characteristics analysis of operation security, combined with expert evaluation and fuzzy prioritization method. The evaluation index system includes four factors of geological conditions, operation environment, slope construction and traffic organization, which lays the foundation for correct evaluation the influence of high slope construction to operation security.

The experiments of vacuum-microwave (VMW) drying on edamames in a deep bed was investigated and compared in terms of drying rate, final moisture content, and quality of dried products among the different heights of edamame in a deep bed. The results have shown that there was a moisture gradient from the top to the bottom of the bed during the vacuum-microwave drying processing, and the greater depth of the bed, the larger the moisture gradient of the bed. Therefore, it can affect the uniformity and the quality of dried products.

The characteristics of hot air and vacuum microwave drying were compared using edamame as the raw material, and an optimized combination drying process was then established thereof so as to achieve increased drying rate and enhanced product quality. Edamame was subjected to 70 °C hot air drying for 20 min, and then microwave dried at power intensity 9.33 W/g for 15 min under −95 kPa (gauge pressure). The optimized combination drying process exhibited significantly shortened drying time as compared with conventional hot air drying, and greatly decreased mass loads on the vacuum microwave dryer.

The characteristics of microwave drying (MD) and combined air-microwave drying (AMD) of bighead carp muscle were studied experimentally. The results show that the moisture ratio (MR) decreases with an increase in microwave drying time when microwave (MW) power is fixed. The drying rate is fast initially and then falls slowly. Finally, the curve of AMD was steeper than that of MD alone during the initial period of 0–120 seconds. The equation MR = a exp (−kt) fitted the data better than other models.