FLAC3D is applied to analyze the stability and the ultimate bearing capacity of upper plate of karst cave under the loading of rectangular spread foundation;and two typical types of rock mass are studied.

There are 11 piers in water, which are partly designed for spread foundation (7 piers) at deep position.

By analyzing the common problems appeared in the construction of spread foundation of bridge in mountainous region,corresponding solutions are put forward,which have some guiding significance for similar engineering.

This paper introduces the practice utilization,the calculating method,steps and reference data of the enlarged type of foundation.

On the basis of particular engineering geology and hydrology of Lhasa River,eight prefabricated open caisson foundations at the main span of the main bridge of Liuwu Bridge are redesigned as row-pile diaphragm wall combined spread foundations.

Application of anchor bolt expanded foundation weight retaining wall in engineering;

This paper recommends the design concept of applying anchor bolt expanded foundation retaining structure in special geography and geology road segment.

Therefore,it is meaningful in practice that designs and calculates for open-cut foundation from two aspects which are bury length determining and checking computation contents of foundation.