Test and analysis on load-bearing characteristics of two types of long piles

Ma´anshan Bridge, located in the vicinity of River Island, spans 36.14 kilometers. The bored test piles, 1.0 meters diameter, the estimate value of supporting capacity is about 11000KN, were used in these areas. Pile SZ-1, SZ-2 was the end-bearing pile and pile SZ3, SZ4 was the friction pile. Based on the way of self-balancing test, the supporting capacity of four piles on the south bank of river have been test and analyzed, including the load displacement curve of pile, the axial force of pile, side friction, and the tip resistance and so on. The main results indicated that under the ultimate load the displacement of end-bearing pile was small and its load-displacement curve was similar to linear distribution; On the contrary the load-displacement curve of friction pile has the downward bend tendency. From the measured friction of the pile, it can be seen that actual value of end-bearing pile side resistance was quite closed to the forecast while the value of friction pile was large than the guesstimate, and the corresponding displacement was small. It showed that the bearing capacity of his kind of pile foundation was conservative.