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AbstractThe present work identifies the qualitative hydro-elastic contributions to fatigue damage on large volume monopiles intended for use in the offshore wind energy industry. Although aerodynamic effects cannot be neglected in a complete dynamic analysis of the structure, the scope of this work is limited to wave loads and soil effects on a turbine in simplified operational conditions. As the rotors are scaled up to improve effciency and reduce the overall costs in wind farms, the foundation and support structure dimensions are increased. As a result, the fluid-structure interaction becomes important for wave-lengths comparable to the characteristic size of the structure. The importance of including diffraction effects is present in the results. Also, the contributions from ringing type response in a fatigue-limit sea-state is investigated by applying the third order Faltinsen, Newman, Vinje (FNV) formulation. Hydrodynamic loading is applied as particle velocities in a spatial time variant grid for first and second order wave theories in long crested irregular waves. Additionally, the second order diffraction forces are calculated using an internationally recognized panel code for second order sum-frequency diffraction forces.

AbstractThe present work identifies the qualitative hydro-elastic contributions to fatigue damage on large volume monopiles intended for use in the offshore wind energy industry. Although aerodynamic effects cannot be neglected in a complete dynamic analysis of the structure, the scope of this work is limited to wave loads and soil effects on a turbine in simplified operational conditions. As the rotors are scaled up to improve effciency and reduce the overall costs in wind farms, the foundation and support structure dimensions are increased. As a result, the fluid-structure interaction becomes important for wave-lengths comparable to the characteristic size of the structure. The importance of including diffraction effects is present in the results. Also, the contributions from ringing type response in a fatigue-limit sea-state is investigated by applying the third order Faltinsen, Newman, Vinje (FNV) formulation. Hydrodynamic loading is applied as particle velocities in a spatial time variant grid for first and second order wave theories in long crested irregular waves. Additionally, the second order diffraction forces are calculated using an internationally recognized panel code for second order sum-frequency diffraction forces.

Abstract The presented work deals with hygro-thermal numerical simulation and mould growth risk evaluation between concrete foundation and frame of multi-story building made of CLT element modules. Structural CLT modules represent an approach towards wood material utilization in construction as its strength achieves markedly higher values then common structural wooden elements and makes rapid erection of the building possible. Although there are great promises that the novel CLT structures will gain ground in high-rise buildings market with apparent benefits in sustainability and inhabitant comments regarding ambience and acoustics, it is important to analyse their structural health and hygro-thermal conditions. The highest risk of unfavourable hygro-thermal conditions is usually presented in location characterized by thermal bridge, such as foundation, window-wall, wall-roof and wall-floor junctions. It is also of significant importance to analyse junctions between materials, whether wood, composite, mortar or concrete. A certain combination of thermal and humidity conditions in exposed time causes mould growth initiation that may lead to deterioration of structural material and unhealthy indoor environment. In this case study, the moisture content and air-flow in the junction and open space in structural design details between the first floor (of concrete) housing joint warehouse and technical spaces and the residential upper floors made of CLT modules is analysed. Conditions leading to probable moisture-derived mould issues and design parameters leading to sufficient ventilation according to Mould Index modelling are presented.

Abstract The presented work deals with hygro-thermal numerical simulation and mould growth risk evaluation between concrete foundation and frame of multi-story building made of CLT element modules. Structural CLT modules represent an approach towards wood material utilization in construction as its strength achieves markedly higher values then common structural wooden elements and makes rapid erection of the building possible. Although there are great promises that the novel CLT structures will gain ground in high-rise buildings market with apparent benefits in sustainability and inhabitant comments regarding ambience and acoustics, it is important to analyse their structural health and hygro-thermal conditions. The highest risk of unfavourable hygro-thermal conditions is usually presented in location characterized by thermal bridge, such as foundation, window-wall, wall-roof and wall-floor junctions. It is also of significant importance to analyse junctions between materials, whether wood, composite, mortar or concrete. A certain combination of thermal and humidity conditions in exposed time causes mould growth initiation that may lead to deterioration of structural material and unhealthy indoor environment. In this case study, the moisture content and air-flow in the junction and open space in structural design details between the first floor (of concrete) housing joint warehouse and technical spaces and the residential upper floors made of CLT modules is analysed. Conditions leading to probable moisture-derived mould issues and design parameters leading to sufficient ventilation according to Mould Index modelling are presented.

AbstractIn this paper a new approach is presented to detect damage of transmission tower. Models are created in sap2000,and white noise is adopted as stimulus signal.A number of monitoring points are arranged on primary steels to receipt signal.Empirical mode decomposition (EMD) is used to decompose response signal that has occurred in the same position on transmission tower before and after damage. The response signal of various intrinsic mode function is got. shape factor is used to quantitate analysis the response signal of the structure of intrinsic mode functions. To contrast shape factor of the intrinsic mode function of response signal that the structure is damaged before and after. Then it can judge the damage on the structure intuitively. The method can better carry out the transmission tower of the damage identification.

AbstractIn this paper a new approach is presented to detect damage of transmission tower. Models are created in sap2000,and white noise is adopted as stimulus signal.A number of monitoring points are arranged on primary steels to receipt signal.Empirical mode decomposition (EMD) is used to decompose response signal that has occurred in the same position on transmission tower before and after damage. The response signal of various intrinsic mode function is got. shape factor is used to quantitate analysis the response signal of the structure of intrinsic mode functions. To contrast shape factor of the intrinsic mode function of response signal that the structure is damaged before and after. Then it can judge the damage on the structure intuitively. The method can better carry out the transmission tower of the damage identification.

Abstract Several clayey materials incorporating different percentages of leaves and small branches derived from the pruning of olive trees were prepared and tested in Thermophysical Laboratory of Polytechnic University of Bari. Hygrothermal properties were measured according to technical standards. In order to consider the potential of earthen materials to improve indoor comfort, the software WUFI ® Plus was used to simulate the hygrothermal behavior of a Test Building, placed in a Mediterranean climate. The analysis was carried out considering the internal surface of the walls of the building covered by two different plasters i.e. gypsum plaster and clayey plaster with 6% of olive waste. Results demonstrated that when considering an unconditioned scenario (without HVAC system) the clayey plaster lead up to a greater improvement of the hygric performances, unlike traditional coverings as gypsum plaster. However, in presence of HVAC system any significant variations occurs in terms of energy saving.