Introducing the first application of composite foundation with cast?in?place plain concrete pile driven by auger rig in Beijing, comparing it with prefabricated reinforced concrete piled foundation and other composite foundation,analyzing it from the aspects of economics,technique,construction and project time.

The article introduces the construction technique of long-screw drill grouting piles,based on the engineering actuality,for the reference of similar projects.

The structure analysis and construction cntrols in the stage of concrete-filled steel tube in the construction of heyan Jialingjiang CFST bridge;

Quality control of concrete filling piles;

During a certain period of time,the mudcake around the concrete filling pile will thicken along with holing time,while the ultimate bearing capacity of the pile will decrease along with the thickening of the mudcake.