The achieved results show that the new-type CRG piles can utilize comprehensively the high bearing capacity of rock on the bottom of piles and the high strength of the body of prefabricated pipe piles,so the bearing capaci.

CRG piles testing study in granite bearing layer;

The design method of CRG piles(Concrete Reinforced Grouting Piles)which get the national invention patent could be taken as the design of the embedded-rock piles and the calculation formula is presented.

CRG piles (Concrete Reinforced Grouting Pile) are introduced by authors, the design method and construction technological process and standard of quality testing are illustrated.

The main structure of hammer head of new-type hydraulic pressure hammer;