The potential for decreasing timber transportation costs in the South by increasing truck payloads was investigated using a combination of theoretical and case-study methods. A survey of transportation regulations in the South found considerable disparities between states. Attempts to model the factors which determine payload per unit of bunk area and load center of gravity location met with only moderate success, but illustrated the difficulties loggers experience in estimating gross and axle weights in the woods. A method was developed for evaluating the impact of Federal Bridge Formula axle weight constraints on the payloads of tractor-trailers with varying dimensions and axle configurations. Analysis of scalehouse data found log truck gross weights lower on average than the legal maximum but also highly variable. Eliminating both overloading and underloading would result in an increase in average payload, reduced overweight lines, and improved public relations. Tractor-trailer tare weights were also highly variable indicating potential for increasing payload by using lightweight equipment. Recommendations focused first on taking steps to keep GVW’s within a narrow range around the legal maximum by adopting alternative loading strategies, improving GVW estimation, and using scalehouse data as a management tool. When this goal is achieved, options for decreasing tare weight should be considered. Suggestions for future research included a study of GVW estimation accuracy using a variety of estimation techniques, and field testing of the project recommendations. / Ph. D.

The objective of this study was to investigate and compare the brokered transport costs of road and rail transport for the independent timber growers of NCT Forestry Co-operative Limited in Kwa-Zulu-Natal. Reliability, flexibility, visibility, rates and total transport time were evaluated for each mode of transport. The impact of the carbon emissions was also considered and the option of performance based standard vehicles investigated. During the period 2000 to 2003, rail was the dominant mode of transport. However from 2004 onwards, due to the diminishing service levels and the high tariff structures of rail transport, road became the preferred mode of transport. The results of the survey conducted for the purposes of this study showed that although road transport outperformed rail transport, rail transport scored significantly higher than road transport as a cost-effective mode of transportation. Rail transport was shown to be a far less carbon intensive mode of transport than road transport, while there were substantial cost savings and benefits from performance based standard vehicles. / Transport Economics, Logistics and Tourism / M. Com. (Logistics)