The invention discloses a high-
pile wharf foundation
pile damage diagnosis method based on structural residual
modal force. The method includes the steps that a finite
element model of a high-
pile wharf foundation pile structure is established, the structure is divided into a plurality of units, and each unit comprises two nodes; an acceleration sensor is arranged on each unit, and
modal test data detected under
natural environment excitation are recorded and saved;
modal parameter recognition is performed on the modal
test data, and a low-order modal frequency and a vibration mode of previous orders are recognized;
model correction is performed, and a reference finite
element model is obtained; under the non-damage and damage condition, a
rigidity matrix and a
mass matrix of each unit are extracted; and each freedom-degree residual modal
force vector in each unit is calculated, when the absolute value of each freedom-degree residual modal
force vector in each unit is larger than a set value, it is judged that damage exists, and the position where structural damage is located is positioned according to the nodes corresponding to freedom degrees. Only through low-order modal information generated before and after structural damage, damage diagnosis can be performed under the condition that the structure has single damage and multi-site damage.