Methods and Devices for Technical Diagnostics of Long-term Concrete Structures

Abstract

The analysis of available publications and patents related to methods and means (devices) for non-destructive testing and quantitative status estimation of long-term concrete and reinforced concrete structures damaged by cracks and/or other dangerous defects is given. The authors provide and characterize a classification scheme for non-destructive testing methods used to determine initial mechanical parameters of concrete and reinforced concrete building structures and those degraded during operation. They consider and evaluate the conventional in building practice techniques and monitoring devices for technical diagnostics of damaged concrete structures. They also analyze the main physical and mechanical methods for laboratory testing of concrete and reinforced concrete specimens as well as methods for technical diagnostics of the status of structures of long-term service. The presented methods include visual inspection, optical, acoustic (or ultrasound), and radiation techniques and devices for crack and/or defect detection and sizing. Description of electrochemical techniques and devices for measuring the extent of degradation in steel concrete reinforcing elements with the aim of making decisions as to the possibility of further reliable use of the concrete and reinforced concrete structures damaged by cracks and/or other defects is provided. Case studies of use of up-to-date technical diagnostic devices for such purposes are considered. The design of a computerized truck-mounted mobile diagnostic-restoration complex for major repair of the sewage collectors and main pipelines is developed. Operational parameters of diagnostic or processing devices, appliances and systems of the complex are included. Practical implementation of the complex in industrial and municipal building structures is illustrated.