On The Relationship Between Natural Frequency And Damping Ratio Of Single Pile

Pile is a prevailing mode of foundation in geotechnical engineering. The pile foundation is the concealed work, so to assess pile load capacity and to assess pile integrity has always been of concern. Dynamic load testing is used to assess pile integrity .The foundation of the theory of Low Strain Integrity Test is wave equation analysis and theory of pile vibration. Due to its simplicity, speed of execution and low cost, Low Strain Integrity Test has been widely applied in pile integrity test. However, due to the differences between theoretical model and actual practices, in engineering practice, the adoption of the soil damping coefficient around the pile not only still has to rely on the pile static loading test , but also on geological conditions and pile type. And the pile test results, due to testing personnel experience vary,affecting the validity and reliability of the test method.This paper is based on the vibration theory of pile,applying the rationale between frequency of vibration of pile and pile length, to determine the broken place of the pile. With noregard to the damping coefficient around the pile, the method is simple and its effectiveness has been confirmed by a practical engineering case.