The paper presents experimental and numerical investigations on the behaviour of rubberized concrete short columns confined with aramid fibre reinforced polymer (AFRP) subjected to compression. Additionally, the possibilities to substitute fine aggregate with crumb rubber granules, obtained from discarded worn tires, in structural concrete is also assessed. Because replacing traditional concrete aggregates by rubber particles leads to a significant loss in compressive strength, the authors highlight the use of AFRP confinement to partially or fully restore the compressive strength by applying a number of 1, 2, and 3 layers. Analytical models available for confined regular concrete are used to predict the peak stresses and the corresponding peak strains. Some analytical models give accurate results in terms of peak stress while others better approximate the ultimate strain. The full stress-strain curve of rubberized concrete and the experimentally obtained values for the material properties of AFRP are used as input data for the numerical modelling. A good agreement is found between the results obtained for the peak stress and corresponding axial strain from both the numerical simulations and the experimental investigations.

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Concrete is a building material with a continuous demand in the construction industry due to the convenient price-performance ratio. On the other hand, concrete is not an environmentally friendly material. Thus, in order to obtain a sustainable material, wood waste can be recycled and used as light aggregates in the manufacture of precast ecological building blocks. Block walls must satisfy not only structural criteria but also functional requirements. In addition, thermal contribution is important in reducing energy consumption over the life of the building. The presence of moisture on the exterior walls due to the appearance of condensation will decrease the thermal performance of building materials. This paper analyses the occurring of condensation risk and its location in the outer wall made of wood-concrete blocks by the Glaser method, for different situations of arrangement and composition of the layers.

Due to the rapid expansion of urban areas around the world and the ever-increasing number of reinforced concrete (RC) structures serving a variety of functional purposes, their behaviour in case of major seismic events has become of great interest to researchers and decision makers alike. Although initially designed to ensure certain levels of safety in case of earthquakes, the damage accumulated in a reinforced concrete structure during its lifetime due to seismic events will ultimately require its strengthening in order to comply with the new seismic design regulations. The paper presents the results obtained by numerical analyses of the seismic performance of a scaled-down RC frame structure retrofitted with a composite membrane. The 1/3-scale symmetric structure was designed according to the specifications of the European norms and following the guidelines in the national annex for Romania. The RC frame structure was previously damaged during a series of shake table tests. The numerical model was developed based on the initial undamaged state of the frame structure and was validated by comparing the numerical results to the experimentally obtained results. A non-linear time history analysis (THA) was used in order to account for the damage accumulation in the model from one seismic record to the next. Modal analysis was run after each non-linear THA to determine any change in the fundamental period of vibration. The seismic record consisted in an artificial earthquake generated according to Eurocode 8 using soil type C spectrum, the amplitude of which was gradually increased from one loading scenario to the next. The numerical model was then updated to include the effect of strengthening by means of composite membrane. The obtained results were used to estimate the outcomes of a new series of shake table tests on the strengthened model following the same loading set-up in terms of seismic motions.