Low Strain Reflection The Bofa Ji Pile Testing Of Theoretical Research And Applications

As one of the dynamic testing methods for structural integrity of pile shaft, it is widely used in the engineering project in our country. However, this method is still one developing practical technique, there are lots of problems remaining unsolved in its practical application. Misunderstanding and contusion were produced during its application, which must be hindering its development normally.Types of piles, the quantitative problems of piles and the theoretical foundation of reflected wave is introduced in this paper. Based on the nature of excitation wave, the author proposes the method of calculating the depth of the reflection interface. At the same moment, it is discussed that include in the basic characteristics of excitation wave, reflected wave as well as synthesis wave superimposed by excitation waves and reflected wave in different phase. Next, the form about deducing defection in the pile is summarized through analyzing feature of vibration curve, geological factors and the impact in the construction process. Then, summing up experience in engineering practice, the author studies the basic characteristics and reason of transverse reflection wave appearing on the top of pile, as well as indicates the method for elimination of transverse wave interference on the top of pile. Finally, the specific applications are analyzed.