NDT Methods Suitable for Evaluation the Condition of Military Fortification Construction in the Field

Abstract

The protective structure is designed to protect the live force against the impact of a shock wave and projectiles, it cannot be diagnosed by the destructive method which devalues the protective structure by sampling. The authors are looking for a combination of suitable non-destructive technology (NDT) methods that would be used in the future to prove the degree of damage to cement-based protective structures after an explosion. This article represents the first part of an experiment designed to verify the applicability of NDT methods, to evaluate the degree of damage of the protective structure in the field. The experiment consists of three parts. The first part is a laboratory verification of the initial material characteristics of the materials used. The first test set of structural elements is made of steel fiber-reinforced concrete. The elements are evaluated using NDT methods and for comparison by destructive laboratory methods. The second part is the impact of structures using explosion and evaluation of the condition of structures using NDT methods in the field. The last part is used to verify the results of the NDT method, which ensures the residual strength of the structure in the laboratory and try to find the relationship between changes in the results of NDT methods and the residual strength. Radiography was included in the introductory and concluding parts of the experiment to verify the results. Although this method is not suitable for using in-situ, it is the only standardized method of the NDT methods used.

The Development of Controlled Orientation of Fibres in SFRC

“…Fibre-reinforced concrete “SFRC” is a composite material with better qualitative strength characteristics than plain concrete. Thus, the distribution of fibres significantly affects the resulting mechanical properties and performance of the composite [ 8 , 9 , 10 , 11 , 12 ]. All the properties of fibre reinforced concrete are, in real use, able to meet the computing and model requirements, especially when meeting the condition of uniform fibre dispersion.…”

Nondestructive Evaluation of Aluminium Foam Panels Subjected to Impact Loading

“…CT was applied in the damage detection of AHS panels with GFRP skins [5] and aluminium skins [10,28]. Other studies [29,30] characterised composite materials subjected to impact tests, not only investigating the damaged area, but also the internal damage, including the internal structure and fibre breakage on the various layers of the composite structure. Hou et al [31] analysed the challenge in the development of innovative computer-aided techniques for automatic detection from radiography images due to the limitation of human interpretation for this test method.…”

Experimental Campaign to Verify the Suitability of Ultrasound Testing Method for Steel Fiber Reinforced Concrete Fortification Structures

“…Because of these reasons, a method of evaluating the condition of these structures using a combination of non-destructive methods that could be used in situ was sought [4,5].…”

“…This article follows up on the study [5] which documents the preparatory phase of experimental measurement. It describes the material batch A2, which consists of rectangular thin slabs with dimensions of 700 × 700 × 60 mm and made of SFRC (steel fiber reinforced concrete).…”