Abstract: This paper presents a case history of the construction procedures of a large cross section underpass underneath a railway at Jingguan Boulevard North in Xiaoyi City. The selection of construction procedures in the large cross section underpass, launching and receiving of horizontal tunneling techniques as well as the mechanics of horizontal tunneling are introduced in the paper. The selection of tunneling segment length and other parameters are also presented. The construction results indicate that the launching and receiving method has the advantage of working a limited space. This method provides a solution to the construction of underpass with horizontal tunneling in long distance under limited space.

Key words: Underpass, Horizontal Boring, Launching and Receiving Method, Construction Techniques