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By way of example we analyze various risks exist in auto spare parts transportation, building engineering logistics risk evaluation index system of auto spare parts transportation, and the introduction of AHP, be more rational auto spare parts transportation risk assessment methods, strengthen risk management auto spare parts auto spare parts transportation to provide a reference for other engineering logistics auto spare parts transportation.

Stacking of bulk solids in terminals, ships, trains, and other bulk solids storage yards is always challenging, considering the requirements of optimal utilization of storage areas. In this study, stacking shapes of a variety of bulk solids with different particle sizes were tested, and the curved shapes of the stockpiles were extracted to establish the actual three-dimensional models of the bulk solids accordingly. The three-dimensional curved stockpiles were used to design the bulk solids stacking strategy where the bulk stacking locations, the stacking volume, and the stacking flatness were optimized. A modified golden section method with a self-influenced factor was developed to improve the calculation efficiency of the stacking algorithm for bulk solids stacking flatness. Furthermore, the bulk solids stacking strategy and algorithm were verified by experiments. The results showed that the curved three-dimensional models were very close to the actual shapes of the bulk solids stockpiles, while the improved golden section method was more accurate and efficient than the traditional golden section method in determining the optimal values of the stacking volumes in terms of flatness. For the different bulk solids tested, the experiment results showed that good flat stacking can be achieved by using the developed stacking strategy.

One of the main reasons for the damage of reinforced concrete is the expansion caused by corrosion of steel bar in concrete. In this paper, the equivalent circuit that inflects corrosion process of steel bars in reinforced concrete was analyzed, with the A.C.Impedance Spectrum method. And the effects of surface treatment of the bars on corrosion resistance of the reinforced concrete were investigated. Study results show that the surface coating (plating) on the built-in reinforcement can effectively prevent corrosion of steel bar, thereby enhancing the durability of concrete structures.

At present, there are some new research ideas in the design of luffing mechanism of portal crane, such as genetic algorithm and particle swarm optimization algorithm. The development of design software adopts Visual C++ or Visual Basic, MATLAB and other tools. These methods are advanced but inefficient because extra time and cost are required. This paper proposes a modern design method to complete the optimization of the four-bar luffing mechanism in the portal crane, which can simplify the calculation and improve the efficiency. The motion track description and mechanical properties of the four-bar luffing mechanism are obtained by the geometric analysis and the load analysis. The luffing curves, which can be re-drawn by modifying the initial parameters, are given to verify the optimized results. Results demonstrate that the modern design method can accomplish the optimal design effectively without extra time and cost, and this finding will be provided as the design guidance for the luffing mechanism.