| Overweight/oversize (OW/OS) cargo is also named after out-of-gauge freight, bulky and length cargo, heavy cargo, massive-product, abnormal load. The increasing demand for OW/OS cargos grows rapidly along with the construction of large-scale projects in globe. The OW/OS cargo has features of long production cycle, small batch and high value, hence research on the safety of this type of cargo during transportation is more important than other cargo.The most commonly used transportation modes for OW/OS cargo are waterway transportation, railway transportation, road transportation and land-and-water co-ordinated transportation. Traditional safety assessment methods for transportation mainly depend on the experience of decision-makers. It is very hard for decision-makers to achieve the accurate data and even some data can not be handled properly because of the lack of theory. After analyzing the characteristics of OW/OS cargo's transportation, one systematical, comprehensive and reasonable safety assessment method is proposed and presented in the thesis which combines with vehicle driving theory, finite element theory, analytic hierarchy process (AHP), fuzzy comprehensive evaluation method (FCE) and accident-causing theories.AHP-FCE is adopted as the main safety assessment method which combines the advantages of AHP and FCE. Firstly, AHP is used to build goal layer, factor layer, index layer according to the actual transportation conditions, and contribution to layers are then obtained through expert evaluating method and AHP. Finally, the FCE is employed to assess the system safety.In order to avoid human factors'influence on membership-calculating in FCE, the actual transportation environment is taken into account. By using the related theory to revaluate the factors'membership in the index layer, the influence of human factors is reduced to the minimum.The stowage of trailer tractor and axis configuration of platform lorry are firstly calculated in view of vehicle safety. Secondly, the finite element analysis (FEA) is applied to the safety evaluation where the acceleration is existence during vehicle' starting and breaking. In addition, the influence on the lashing steel wire ropes was taken into account. The impact factors include the unevenness pavement, friction, severe weather and strengthening modes for cargo. Thirdly, the cargo stability of sliding and overturning under different strengthening ways and road condition were computed according to traditional stability calculation theory. Finally, value of membership is adjusted based on calculation results which mentioned above, thus accurate safety assessment result can be achieved.There would be an accident risk in the land-and-water coordinated transportation when unloading cargo on the temporary wharf without any large lifting equipment, In this study, it is the first time to develop a new floating self-adaptive unloading system to prevent the occurrence of accidents. After using of this system, the height of the unloading beam could be adjusted automatically without the ballast water regulation. Thus, the accidents caused by the sudden leaping of the ship could be avoided effectively. The numerical experiment results show that the proposed system can adaptively regulate the unloading process and keep the procedure of unloading in safe efficiently as well.To further enhance the accuracy of membership values, a novel measuring system for vehicle's passing ability in space is proposed in this thesis. The proposed novel system has been authorized as a national invention patent. It can quickly record the information of the road condition, such as road inclination, the maximum allowance in height, the largest allowance in width, and the maximum acceleration, etc. Through the combination of unknown information and analysis results, the membership of the related evaluation in the fuzzy matrix can be refreshed and consummated. Therefore, the accurate assessment results could be attained.To evaluate and validate the proposed safety methodology based on FCE, a special designed experiment is presented in this thesis. This experimental system is used to monitoring the transportation physical quantities which is developed based on Visual Basic 6.0. These physical quantities include road inclination (heel and trim), tension in lashing steel wire rope, speed, and acceleration of vehicle, etc. A series of experiments was implemented for the platform lorry with cargo which weights 147 tons in Three Gorges underground converter substation on January 2011. The test results suggest that the proposed transportation safety assessment system is feasible for practice use.
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