an earthquake with magnitude Mw = 6.4 occurred in the city of Durrës, with epicenter about 16 km southwest of Mamurras. This seismic event caused 51 loss of life, hundreds injured and hundreds of damaged buildings. One of the typified structures, identified by the authors with the most cases of damage or even collapse, is the structure Type no. 82/2 built in some areas of the city of Durrës, in the period 1983-1993. The purpose of this study is to analyze the behavior of this type of structure during seismic loading (for two cases, five and six storey, from the same typology), using the non-linear static procedure (Pushover). The obtained results are compared with the damages recorded in the field for these buildings, concluding with their main causes. According to this study it appears that the main cause of failures occurred in this type of building is the reduction of the reinforcement amount from the ground floor to the first floor by 35.5% and percentage of reinforcement required for the given section exceeds the requirements of design standards (Eurocode-2 and KTP-2-89) by around 30%. Also on these failures contribute the low strength of concrete used in construction of some of these buildings (the compressive strength results 50% less than required) and the use of smooth rebar.

The joints of the human body act as mechanical or building structures joints. Joints connect different segments by enabling the movement of these segments. The design of a joint that provides durability or static support differs from that one which provides only movement. Joints of the human body, as organic joints, are considered more complex than other types of joints. Finite element models help to comprehend the knee structure behavior under the action of dynamic and static loads. Deformations in the articulating cartilage and the distribution of loads from meniscus provide data to understand the effect of loads in different parts of the knee. This study aims to calculate the stresses in the contact area of the tibiofemoral joint, using the finite element model. During this process, it will be an approximation of geometric shape of the femur, tibias and articulating cartilage to their real shape, taking into account the physic-mechanical characteristics of their components. The study, based on results of numerical calculations, aims to provide practical recommendations for dimensioning the tibiofemoral articulating cartilage and for the quality of the materials, to be used in knee prosthesis industry.

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In this paper, reference is made to the key features of ACI, EC2 and other models, regarding SLS calculations of FRP reinforcement concrete and the comparison with steel reinforcement concrete formulas, especially focusing on deflection. Mechanical characteristics of FRP materials, such as lower elastic modulus, lower ratio between Young's modulus and the tensile strength, lower bond strength of FRP bars and concrete, compared to steel reinforcement, make that SLS results determine the design of FRP reinforced concrete, based on the serviceability requirements. Different parameters influences affect the stresses in materials, maximum crack width and the allowed deflections. In this study we have calculated only the deflections of FRP-RC beams. Concrete beams reinforced with glass-fiber (GFRP) bars, exhibit large deflections compared to steel reinforced concrete beams, because of low GFRP bars elasticity modulus. For this purpose we have used equations to estimate the effective moment of inertia of FRP-reinforced concrete beams, based on the genetic algorithm, known as the Branson's equation. The proposed equations are compared with different code provisions and previous models for predicting the deflection of FRP-reinforced concrete beams. In the last two decades, a number of researchers adjusted the Branson's equation to experimental equations of FRP-RC members. The values calculated were also compared with different test results. Also it is elaborated a numerical example to check the deflection of a FRP-RC beam based on various methods of calculation of effective moment of inertia and it is made a comparison of results.

During their lifetime, the capacity of the single elements or of the entire structures is not anymore adequate to the static and dynamic functions requested by the project, mainly caused from deterioration of the masonry structures or the change of the destination and the purpose of the elements. Externally bonded FRP may be used in a repair capacity for structures that have moderate earthquakes damages or to reinforce structures considered to be vulnerable. The FRP strengthening systems are used mainly for flexural and shear strengthening of the structural elements subjected to bending moments and shear forces larger than their flexural and shear capacity, especially the beam-column joints. Many experiences in rehabilitation of damaged masonry buildings have been carried out in Europe in the last decades. Several unsuccessful results have underscored the need for adequate assessment prior to any rehabilitation. In fact, when neither the real state of damage nor the effectiveness of repairs is known, the results of the intervention are also unpredictable. In this article there are described different techniques used for reinforcement of masonry structures, with their advantages or disadvantages.