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- An analytical approach to assess the influence of the massive wall material, thickness and ventilation system on the Trombe wall thermal performancePublication . Sá, Ana Cristina Briga; Martins, Analisa; Cunha, José Boaventura; Lanzinha, João; Paiva, AnabelaThe influence of the massive wall material, thickness and ventilation system on the Trombe wall thermal performance was analysed based on an analytical methodology. Results obtained from experimental work will also be added to this study. During the heating season, for the non-ventilated Trombe wall, the global heat gains decrease is not proportional to the thickness increase, and this ratio depends on the massive wall material heat storage capacity. A ventilation system in the massive wall leads to higher heat gains due to the air convection, but this growth is not in the same proportion for the different materials. If solid brick or earth is used, heat gain values are much higher than those obtained if there is no ventilation system, increasing to the double in the case of earth and 2.5 times more in the case of solid brick. When the massive wall is ventilated and made of granite, an increase in the gains of 44.06% is obtained when compared with the non-ventilated. During the cooling season, closing the ventilation system and the external shutter leads to heat gains considerably lower than those obtained during the heating season. In this case, earth can be a suitable material.
- Earth-based construction material field tests characterization in the Alto Douro Wine RegionPublication . Cardoso, Rui; Pinto, Jorge; Paiva, Anabela; Lanzinha, JoãoThe Alto Douro Wine Region, located in the northeast of Portugal, a UNESCO World Heritage Site, presents an abundant vernacular building heritage. This building technology is based on a timber framed structure filled with a composite earth-based material. A lack of scientific studies related to this technology is evident, furthermore, principally in rural areas, this traditional building stock is highly deteriorated and damaged because of the rareness of conservation and strengthening works, which is partly related to the non-engineered character of this technology and to the knowledge loosed on that technique. Those aspects motivated the writing of this paper, whose main purpose is the physical and chemical characterization of the earth-based material applied in the tabique buildings of that region through field tests. Consequently, experimental work was conducted and the results obtained allowed, among others, the proposal of a series of adequate field tests. At our knowledge, this is the first time field tests are undertaken for tabique technology. This information will provide the means to assess the suitability of a given earth-based material with regards to this technology. The knowledge from this study could also be very useful for the development of future normative documents and as a reference for architects and engineers that work with this technology to guide and regulate future conservation, rehabilitation or construction processes helping to preserve this important legacy.
- Structural and material characterization of a haussmann buildingPublication . Cardoso, Rui; Paiva, Anabela; Pinto, Jorge; Lanzinha, JoãoHaussmann buildings are representative of Paris urban architecture. However, those buildings being centenarians, present several pathologies which is preventing their adequate use. Moreover, an upgrade regarding users security, acoustic, thermal and fire requirements is, among others, urgently needed to meet the new standards. Additionally, there is actually, in Paris, an increasing demand for hotel rooms. For those previous reasons, Haussmann buildings are nowadays submitted to heavy operations relative to use changes, conservation, rehabilitation and strengthening. In this paper, a structural and material characterization of a Haussmann building complex located at La Madeleine in Paris is presented. This characterization is the result of a survey realized during the construction stage occurred between 2015 and 2017, relative to use change, rehabilitation and strengthening. The present study allows identifying the existing structural system, the materials and the geometry of the principal structural elements. The knowledge from this study would be very useful for the development of sustainable rehabilitation and strengthening techniques and at the same time helping to preserve this important heritage or similar ones existing in other countries.
- Structural and material characterization of a Haussmann Building Complex at la Madeleine, ParisPublication . Cardoso, Rui; Paiva, Anabela; Pinto, Jorge; Lanzinha, JoãoHaussmann buildings architecture spread throughout the city of Paris. Nevertheless, those buildings are nowadays submitted to heavy operations of use change, conservation and rehabilitation, justified by several reasons, among others are building aging and the increasing demand for hotel rooms in Paris. In this paper, a structural and material characterization of a Haussmann building complex located at La Madeleine in Paris is presented. This characterization is the result of several technical visits realized during construction works stage relative to use change, rehabilitation and strengthening which take place between 2015 and 2017. The present study allows identifying the existing structural system, the materials and the geometry of the principal structural elements in a structural engineering view. The knowledge from this study could be very useful for the development of sustainable rehabilitation and strengthening methodologies, helping at the same time to preserve this important legacy or similar ones existing in other countries.
- An experimental analysis of the Trombe wall temperature fluctuations for high range climate conditions: Influence of ventilation openings and shading devicesPublication . Briga-Sá, Ana; Cunha, José Boaventura; Lanzinha, João; Paiva, AnabelaDespite the studies already developed about Trombe walls, more research work is needed to contribute to the knowledge about their behaviour and optimize it according to the specific characteristics of each climatic region. The ventilation openings and the shading device operation decisively influence the temperatures fluctuation along the system and that impact should be discussed. In this context, a test cell with a classical Trombe wall was submitted to real climatic conditions in a Portuguese city. The effect of ventilation openings and shading devices in the temperatures fluctuation was analysed. The temperatures in the air layer and along the massive wall presented a similar oscillation pattern and exceeded 60 °C without ventilation and shading devices. For this configuration, temperature values at the top of the air layer were always higher than those obtained at the base and a differential of 19 °C was achieved. The temperature fluctuation across the massive wall was not proportional to its thickness due to its heat storage capacity. When the ventilation system was closed and the shading device was not activated, the temperature inside the test cell exceeded the outside temperature value in 9 °C, showing the system ability to store and release heat.
- Experimental and analytical approach on the Trombe wall thermal performance parameters characterizationPublication . Sá, Ana Briga; Cunha, José Boaventura; Lanzinha, João; Paiva, AnabelaAn analytical and experimental analysis on the Trombe wall thermal performance was carried out for different conditions of ventilation openings and occlusion device operation. Experimental results allowed to determine temperature fluctuation, heat flux, heat delay and air velocity at the ventilation openings. A calculation methodology was applied to estimate the heat gains and losses through the system using experimental data. Ventilation openings and occlusion device effect was immediately visible in the temperature fluctuation and, consequentelly, in the heat gains and losses. Experimental results showed that, when there was no occlusion device, massive wall external surface temperature values exceeded 60 °C and, when it was placed, reduced to 30 °C or less. Heat took almost 3 times more to achieve the interior of the test cell when the ventilation openings were closed. Air velocity increased following a diagonally pattern from the bottom to the top of the ventilation opening and its values varied between 0.10 m/s and 0.40 m/s, leading to air flow values between 0.002 m3/s and 0.008 m3/s. The calculation methodology application allowed to determine the total gains through the system for a continuous period. The impact of the system operation on the different thermal performance parameters was observed.