Dynamic and static comparative analyses of settlements of overlength PHC pipe piles

Based on the test results of prestressed high strength concrete(PHC) pipe piles by static and high strain dynamic load testing,Q-s curves of test piles have been achieved;and the relation between the soil resistance and relative displacement between pile and soil is calculated through the stress test.Comparative analysis of the Q-s curves between the dynamic and static load testing is made;and the settlement behavior of PHC pipe piles is discussed.Results show that the settlement of pile calculated by high strain dynamic load testing is higher than that of pile tested by static load testing when load is smaller;and it is smaller than the result of the static load testing when load gets larger.The results also show that the end bearing of the pile can not exert sufficiently when the pile driven into the full efflorescence granite or the higher intensity of the soil in spite of the dynamic or the static load testing;and the Q-s curves of test piles have the character of slow transmutation.