METHOD OF SELECTIVE FADING AS A EDUCATIONAL TOOL TO STUDY THE BEHAVIOUR OF PRESTRESSED CONCRETE ELEMENTS UNDER EXCESS LOADING

Prestressed structures are a key to realization of the boldest architectural ideas, characteristic feature of prestressed structure is better use of concrete material properties by insertion of internal forces. Learning about pre-stressed reinforced concrete structures is an integral part of Graduate Studies Program in construction engineering. Know-how of geometry change patterns in prestressed concrete elements under certain load is essential in understanding the specifics of prestressed concrete constructions. Existing measurement methods widely used in educational laboratory classes, allow to measure the element deformation using only one variable, vertical displacement. Tracking of overall geometry changes of the concrete elements, using conventional methods is impossible. With a view to continuous improvement, as well as the use of the latest achievements of science and technology in the teaching process, a new program of laboratory classes should enable students to learn how exactly structure deforming. Accurate response to this postulate might be remote sensing. Controlled failure of prestressed reinforced concrete beam were carried out in a Regional Laboratory of Civil Engineering at Concrete Structures Department, Gdansk University of Technology, as a part of research focused on optical methods development for the diagnosis of concrete structures. Assessment of geometry changes of pre-stressed concrete beam was performed using terrestrial laser scanning. The authors by using authorial and described in earlier papers, Method of Selective Fading, are able to reproduce the total envelopes of deformation in prestressed concrete element at various stages of the load. Aim of the following paper is to highlight the usefulness of remote sensing in the teaching process, the article contains accurate and factual description of the experiment, and above all provide practical guidance on how to build, set up and configure test station to work with the terrestrial laser scanning. Measurement method developed by the authors is a viable alternative to conventional diagnostic methods commonly used in studies of concrete elements. Diagnostic test taken with teledetection method performed on compressed concrete element was carried out in the presence of a laboratory group of students to intrest them in alternative methods of concrete diagnostic and identify didactic potential of use remote sensing during classes. The laboratory classes scenario is also under consideration in this article.