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In outside constructions (e.g. aircraft frames, bridges, tanks and ships) real‐life noises reduce significantly the capability of location and characterization of crack events. Among the most important types of noise is the rain, producing a signal similar to crack. This paper seeks to present a robust crack detection system with simultaneous raining conditions and additive white‐Gaussian noise at −20 to 20 dB signal‐to‐noise ratio (SNR).

The proposed crack detection system consists of two sequentially, connected modules: the feature extraction module where 15 robust features are derived from the signal and a radial basis function neural network is built up in the pattern classification module to extract the crack events.

The evaluation process is carried out in a database consisting of over 4,000 simulated cracks and drops signals. The analysis showed that the detection accuracy using the most robust 15 features ranges from 77.7 to 93 percent in noise‐free environment. This is a promising method for non‐destructive testing (NDT) by acoustic emission method of aircraft frame structures in extremely noisy conditions.

Continuous monitoring of crack events in the field requires the development of advance noise reduction and signal identification techniques. Robust detection of crack signals in noisy environment, including raining drops, improves significantly the reliability of real‐time monitoring systems in large and complex constructions and in adverse weather conditions.

As far as is known this is the first time that an efficient system is presented and evaluated which deals with the problem of crack detection in adverse environment including both stationary and non‐stationary noise components. Moreover, it provides further information on the engineering and efficiency problems associated with NDT techniques in the aircraft industry.

The corrosion of reinforcing steel bars reduces significantly the life and durability of concrete structures. This critical concern causes great losses to the economy and industry. The purpose of this paper is to estimate the effects of corrosion on the tensile mechanical properties of embedded steel bars B500c in concrete.

The concept is based on the curve fitting modelling, as well the mathematical correlation of the tensile mechanical properties between corroded bare and corroded embedded steel bars. In order to achieve this, extensive experiments were carried out on both bare (Ø8, 10, 12, 16 and 18 mm) and embedded (Ø8 mm) steel bars B500c, which were subjected to artificially accelerated corrosive conditions in a chloride‐rich atmosphere for several exposure times.

The research results show that the estimation method is available and effective in simulating the tensile mechanical behaviour of corroded reinforcing steel bars B500c.

As far as is known, this is the first time that an advanced data processing technique has been employed to try to find the mathematical correlation of the existing corrosion damage on the residual tensile properties between bare and embedded steel bars. It is argued that these models can be developed in order to reduce the need for expensive experimental investigation in materials.

This study aims to develop an innovative actuator for improving the performance of future aircraft, by adapting the airfoil shape according to the flight conditions. The flap’s camber of a civil regional transportation aircraft’s trailing edge actuated and morphed with the use of shape memory alloys (SMA) actuator technology, instead of the conventional split flap mechanism is studied.

For the flap’s members sizing an efficient methodology is utilised based on finite element (FE) stress analysis combined to analytically formulated design criteria. A mechanical simulation within an FE approach simulated the performance of the moving rib, integrating both aerodynamic loads and SMA phenomenology, implementing Lagouda’s constitutive model. Aim of this numerical simulation is to provide guidelines for further development of the flap. A three-dimensional assembly of the flap is constructed to produce manufacturing drawing and to ensure that during its morphing no interference between the members occurrs. Eventually, the manufactured flap is integrated on a test rig and the experimental characterisations under no and static loads, and dynamic excitation are performed.

Experimental results showed that the rib’s SMA mechanism can adequate function under load providing satisfactory morphing capabilities.

The investigated approach is an internal into the flap mechanism based on the shape memory effect of thin wires. In the developed mechanism, SMA wires are attached to the wing structure, where they function as actuating elements.