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Based on the practice of fight against snow and ice covered on the highway in Liaoning Province which lies in the northeast of china, the research results on the impacts of the highway snow-meting agents on the greening vegetation are shown. Then suggestions to reduce the bad impacts are put forward to provide reference for using scientifically snow-melting agents and protecting environment in the paper.

Rigid-plastic finite element analysis (RPFEA) is an efficient and practical method to calculate rolling parameters in the strip rolling process. To solve the system of simulations equations involved in the RPFEA, a numerous of numerical methods, including the standard Newton-Raphson method, the modified Newton-Raphson method, and etc., have been proposed by different researchers. However, the computational time of the existed numerical methods can not meet the requirement of the online application. By tracking the computational time consumption for the main components in the standard Newton-Raphson method used in finite element analysis, it was found that linear search of damping factor occupies the most of the computational time. Thus, more efforts should be put on the linear search of damping factor to speed up the solving procedure, so that the online application of RPFEA is possible. In this paper, an improved trust-region method is developed to speed up the solving procedure, in which the Hessian matrix is forced to positive definite so as to improve the condition number of matrix. The numerical experiments are carried out to compare the proposed method with the standard Newton-Raphson method based on the practical data collected from a steel company in China. The numerical results demonstrate that the computational time of the proposed method outperforms that of the standard Newton-Raphson method and can meet the requirement of online application. Meanwhile the computational values of rolling force obtained by the proposed method are in good agreement with experimental values, which verifies the validity and stability of the proposed method.

This article has analyzed the main cause of cracks in the cement concrete pavement of county-highway and proposed some precautionary measures and disposition measures.The measures of cracks in cement concrete pavement mainly have pressure injection and grouting,expansion seam grouting,directly grouting,striped overlay and nozzle grouting.

During the rolling process, temperature is an important factor that affects the die and the work-piece in metal forming procedure. The metal deformation is often carried along with the variety of temperature. Moreover, mechanical energy of plastic deformation is converted into heat during the metal deformation process. Thus, it is necessary to couple the deformation and thermal behaviors in an integrated manner in numerical simulation so as to improve the simulation accuracy. In this paper, we use a 3D rigid-plastic Finite Element Method (FEM) to simulate the hot rolling process by coupling the thermal effects. Based on the 3D FEM model, integrated equations of coupling velocity and temperature fields are formulated. The uniform of integrated equations is obtained by re-indexing the combination sequences and then a modified coupling method is proposed to solve the resulted equations. The numerical experiments are carried on the real data collected from a steel plant. A good agreement between the numerical result and measured value shows the availability of the proposed coupling method.