Research is conducted on the causes of damage and the structural integrity assessment of the bucket-wheel boom welded lattice structures, before and after the repair of vital structures. Additionally, the paper describes the investigation conducted based on the results of non-destructive tests (visual-, magnetic particle-, dye penetrant-, and ultrasonic tests), results of tensometric measurements that refer to the stress-strain state, and results based on numerical calculation of stresses by finite element method, performed through the use of a 3D model in the software Radimpex Tower 6.0 (R). The results of tests and research performed after the repair of damaged structural welded sections show that the operational procedures are being obeyed
