A Study Of The Techniques Of Railway Bridge And Culvert Construction In Perennially Frozen Soil Zone

Qinghai-Tibet Railway (Section of Germu to Lhuasa) is 1 118 km long ,of which 965 km long line passes through the plateau at the altitude over 4 000 m , and 550 km long line passes through the continued permafrost soil. It will be the railway with the highest altitude in the world. Moreover, Qinghai-Tibet Railway will be the first railway to be constructed on such plateau with widely spreaded permafrost soil.The engineering geological phenomenons of permafrost soil will produce the bad effect on railway construction and operation administration. For example, the frost heaving and thaw collapse of frost soil will directly affect the stability of the bridge and culvert. The two key technical problems to be faced in railway construction and operation administration are plateau (with altitude over 4000 m) and frost soil, which includes permafrost and seasonal frost soils.In this paper, the engineering geological problems of the plateau in related to the railway to be constructed in permafrost soil zone were introduced and analyzed, Based on that, the effect of frost heave, thaw collapse along with the impact of serious environmental conditions on the construction of railway bridges and culvert at the plateau were discussed. This leads to the development of a whole series of techniques with regard to construction of bridges and culvert. These techniques include a dry method of bored pile, a high anti-frost enduring concrete construction technique, and a pre-caste spelling culvert construction technique. Good technical and economy results were obtained through the application of all these techniques. Finally, the whole series of techniques were bringed forward, the results were made use of to guide the engineering construction, and to obtain the good practical results.