Global population growth leads to a rapid urbanization of big cities and the development of transport infrastructure (airports, railway and bus stations). The strong urbanization in the cities of developing countries leads to a gradual rapprochement of dwellings and companies of airport zones. A fact that is real in Mali, where Bamako airport area has become an inhabited urban zone for some years by a part of the population. Given the importance of Bamako's airport traffic (West African crossroads), the proximity of the dwelling houses must receive the authorities and scientist's attention on the occupants' safety and quality life. The noise levels generated all around the airport zone throughout landings and takeoffs by different aircraft types require an assessment of the acoustic noise level, the level of noise exposure and the building acoustic performance near the airport for users comfort and quality of life. In this article, we give in one hand the general notions on the inhabitants discomfort indicators, the building acoustics and, on the other hand, non-quality identification, and the discomfort factors whose resolution contributes to improving the building acoustic and environmental performance. These assessment studies are based on acoustic measurements and in-situ surveys from construction actors and users. Data from these surveys are processed with an evaluation methodology developed to improve knowledge and strategies aimed at preventing or minimizing the acoustic risks near airports. The capitalization of knowledge resulting from this study can serve as experience feedback through good practices advocacy and corrective and preventive solutions for building construction and renovation projects.

In this work, the objective was to correlate anisotropy with the mechanical and microstructural behavior of two high strength steels used in vehicle production in order to obtain variables to alter future manufacturing processes in order to obtain steels with a lower elastic return, known as springback effect, which means geometric changes suffered by the part at the end of the plastic deformation process, after the release of the forces applied by the stamping tool and this causes dimensional failures that compromise the production. In this research, biphasic steel and one low carbon steel were evaluated, being Docol_DL800 and LC200 their trade names, respectively. Tensile tests and three-point bending in air were performed to determine the mechanical properties and behaviors and these results were compared with those obtained by computational simulation using the finite element method and were also correlated with microstructural data from the backscattered electron technique. The results indicate that biphasic steel has a higher hardening allowing a greater springback effect due to its microstructure with ferrite and martensite, high grain refinement, greater amount of elastic residual energy and a lower degree of disorientation after mechanical conformation, creating the effect Bauschinger. Already the steel LC200 presented a smaller degree of springback thanks to the more isotropic hardening due to the increase in the degree of grain disorientation after the conformation. Thus, it was concluded that the manufacturing processes of these steels should seek to combine high mechanical strength with a more isotropic behavior.

France is a country composed of moderate seismic hazard regions but however vulnerable to earthquakes. Indeed, only a few parts of existing buildings have been built using paraseismic regulation. Several current large-scale seismic vulnerability assessment methods are used, as Hazus or Risk-UE, but they are inappropriate to the analysis of a specific building. In our case, we use an experimental approach to study the elastic behaviour of existing buildings: ambient vibration analyses seem to be an interesting way to determine the vulnerability. Ambient noise testing with Output-Only Modal Identification is a low-cost non-destructive method to provide vibration data from civil engineering structures like buildings. The interest of this method is to obtain dynamic parameters with only natural excitations: wind, traffic, human activity... In the frame of the “Plan séisme des Hautes-Pyrénées”, the building considered is the relatively regular 18-storey Ophite Tower located in Lourdes, France. The vibration measurements are conducted using a 24-channel system connected to an acquisition station. The modal parameters of this building (natural frequencies, modal shapes and damping) are calculated using the stochastic subspace identification method. These parameters, extracted from in situ data, are then used to calibrate a model. Having defined damage level criterion, the response motion, produced by seismic events, will lead to the determination of the vulnerability curves of Ophite Tower.

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