Construction technology of excavation pile under complex topographical and geological conditions of Xiaoqun Bridge by river;

The application of controlled blast in excavation pile construction;

In valley multi-karst caves area,manpower excavation pile may effectively avoid blocking up the hole and leaking the muddy.

On the application of the construction technology excavated pile in building engineering;

Manual-excavated pile foundation has become the chief foundation form because of its advantages.

Based on the construction of large-hole dug pile foundations of the Shengmi Bridge in Nanchang, the construction technology for dug piles under geologic conditions of abundant underground water is briefly presented, while the methods for handling common problems during digging construction of the piles are described in considerable details.

The eolian sand is loose, and not stable particularly at steep slope zone where construction of dug piles is extremely difficult and there are even no ripe experiences to go by.

Give a more detailed description of the design principle that used protection with dug pile in transformation of existing railway bridge and culvert construction in parallel paragraph.