Abstract: According to production practices of Haerwusu Surface Mine,learning from other mines′ advanced experience about the transport system,the idea for building a middle-style “bridge” to form an intermediate bridge transport system at “center of gravity” of stripping materials between work slope and non-work slope is put forward.In accordance with the mine production status of beach pinchout,using mathematical modeling method,the trapezoidal model of stripping materials in the lower level of the mine was established.Then,the model for movement of materials was divided into two parts,the middle bridge transport and the end slope transport.Further comparison with the traditional bridge was made from aspects of automobile transport distance,transport costs,and other economic benefits.The study showed that it is the most economical and reasonable to build the transport bridge along the “center of gravity” in lower level of Haerwusu surface mine.It can reduce the transport work of internal drainage by 29 Mm³·km,and achieves steep end-slope mining.By this method,more than 448 000 t of additional coal resources are recovered each year with overall annual increase of 82.522 Millions yuan in economic benefit.

Key words: Internal dumping, Development haulage system, Middle bridge, Transport work