METHOD FOR DETERMINATION OF RESILIENT CHARACTERISTICS OF PILE AND ENCLOSING SOIL Russian patent published in 2009 - IPC G01N3/10 

FIELD: physics, measurements.

SUBSTANCE: invention is related to methods for determination of resilient characteristics of pile-stands and hanging driven piles of different type and enclosing soil in process of construction or reconstruction of buildings and structures. With the help of digital registration of resilient oscillations from combination of pulse mechanical actions at pile cap and calculation of averaged Fourier spectra from the field of longitudinal oscillations, at least three first frequencies of pile own longitudinal oscillations are identified. Then solving equations in pile model with free upper and resiliently fixed lower ends, using available frequencies, elastic parameters of pile and enclosing soil are defined: longitudinal rigidity of pile for compression - stretching EF, dynamic module of pile material elasticity E, rigidity of side surface to vertical shift K_{Z SH}, rigidity of foundation soil under pile lower end K_{Z F}. Elastic parametres are used to estimate class of pile concrete, and it is compared to the rated one. Rigidity characteristics are used to estimate values of actual bearing capacity of inspected piles by their comparison with analog characteristics for piles tested by static or dynamic loads.

EFFECT: provision of possibility to measure parametres for piles with unevenness of bearing capacity.

6 dwg