Search results for "structural"
showing 10 items of 5047 documents
Energy Optimization of BIPV Glass Blocks: a Multi-software Study
2017
Abstract The aim of this paper is to show the results of the performance analyses carried out on four patented glass block configurations integrated with third-generation Dye-sensitized Solar Cell (DSC) modules. The analyses take into account the thermal, optical and electrical performance by using three different software (COMSOL Multiphysics, WINDOW, Zemax), also enabling to take into consideration the peculiar three-dimensional geometry of this innovative glazed product. Starting from these results, new configurations improved as for the thermal insulation, are also introduced and studied, in order to make further considerations about the applicability of this building component for the …
PCM thermal storage design in buildings: Experimental studies and applications to solaria in cold climates
2017
Abstract As energy availability and demand often do not match, thermal energy storage plays a crucial role to take advantage of solar radiation in buildings: in particular, latent heat storage via phase-change material is particularly attractive due to its ability to provide high energy storage density. This paper analyzes the performance of a building-integrated thermal storage system to increase the energy performances of solaria in a cold climate. A wall opposing a highly glazed facade (south oriented) is used as thermal storage with phase change materials embedded in the wall. The study is based on both experimental and simulation studies. The concept considered is particularly suited t…
Testing of “Global Young's Modulus E” on a rehabilitated masonry bell tower in Venice
2017
Abstract This paper shows the effectiveness of the techniques chosen for the rehabilitation of the historic “Sant'Andrea” masonry bell-tower in Venice. The achieved rehabilitation projects based on the indenting technique consisting in removing and replacing bricks in bad conditions, and on the isolation of the bells at the belfry quote, respect all the constraints represented by the aesthetic and structural features of the building. Moreover, the experimental analyses used to define the existing state of the structure are described in detail. The tower is also an interesting case study for the validation of the proposed method to determine the global young's modulus in a rehabilitated maso…
Sequential design of multioverlapping controllers for structural vibration control of tall buildings under seismic excitation
2012
In this article, a computationally effective strategy to obtain multioverlapping controllers via the inclusion principle is applied to design a state-feedback multioverlapping linear-quadratic regulator controller for a 20-story building. The proposed semidecentralized controller only requires state information of neighboring stories to compute the corresponding control actions. This particular information exchange configuration allows introducing a dramatic reduction in the transmission range required for a wireless implementation of the communications system. More specifically, just a one-story transmission range is required by the proposed multioverlapping controller, while a full-buildi…
A comparative evaluation of crashworthy composite sandwich structures
2007
Abstract This paper describes an experimental evaluation of the energy absorption properties of a series of novel designs for cost-effective crashworthy composite sandwich structures. All the designs are based on the concept of the “tied-core” sandwich, i.e. the use of additional core reinforcements that act to tie the opposing facings of a sandwich together, thus preventing catastrophic failure under edgewise loading. The design, manufacture and crush testing of hollow rectangular tubes fabricated from six different tied-core concepts is described. Factors that are shown to promote high energy absorption include large, continuous areas of contact between the facings and the ties, non-thin …
A multilayer anisotropic plate model with warping functions for the study of vibrations reformulated from Woodcock's work
2013
Abstract In this paper, a suitable model for static and dynamic analysis of inhomogeneous anisotropic multilayered plates is described. This model takes into account the variations of the transverse shear strains through the thickness of the plate by means of warping functions. Warping functions are determined by enforcing kinematic and static assumptions at the interfaces. This model leads to: a 10×10 stiffness matrix coupling to each other the membrane strains, the bending and torsion curvatures, and the x and y-derivatives of the transverse shear strains; and a classical 2×2 transverse shear stiffness matrix. This model has been proven to be very efficient, especially when high ratios be…
A PROCEDURE FOR THE EVALUATION OF INSTALLED PROPELLER NOISE
2001
Abstract A method for the prediction of the acoustics of a propeller in the flow-field of a wing is presented. The method is used to study the noise generated by the unsteady loading induced on the propeller as it passes through the wing flow-field. Both the aerodynamic and acoustic methods are previously proven techniques, the aerodynamic method being based on a combination of free wake analysis and a three-dimensional boundary element method, while the acoustic calculation is a full-surface, moving medium form of the Ffowcs Williams–Hawkings equation. Calculations are presented for a reference case of a four-bladed low-speed propeller in forward flight. The acoustic predictions are supple…
The control of indoor thermal comfort conditions: introducing a fuzzy adaptive controller
2004
The control and the monitoring of indoor thermal conditions represents a pre-eminent task with the aim of ensuring suitable working and living spaces to people. Especially in industrialised countries, in fact, several rules and standards have been recently released in order of providing technicians with suitable design tools and effective indexes and parameters for the checking of the indoor microclimate. Among them, predicted mean vote (PMV) index is often adopted for assessing the thermal comfort conditions of thermal moderate environments. Unfortunately, the PMV index is characterised by non-linear features, that could determine some difficulties when monitoring and controlling HVAC equi…
Studio delle prestazioni di giunzioni incollate ibride (Strength evaluation of structural hybrid bonded joints)
2013
The idea of “hybrid joints” arises from the need of joining together materials, producing a tough, stiff and lightweight joint. The core concept is: use two different joining techniques, with the aim to increase the strength and gather the advantages of each technique, reducing the drawbacks. In this work hybrid joints consist in joints produced with two different kinds of joining techniques: one of them being adhesive bonding and the other being one among Resistance Spot Welding, Pop Riveting, Clinching, Self Piercing Riveting. The performance of hybrid joints are compared with those of traditional joints for the single lap joint geometry, for different geometric (plates thickness, pitch o…
Influence of correlations between stresses on calculated fatigue life of machine elements
1996
The correlation between components of the random stress tensor and its influence on the calculated fatigue life of machine elements were analysed. Three covariance matrices of components of biaxial stress state were considered. They were determined from measurements of strains in an element of a vibrating screen for aggregate, in the back wall of a bus, and in a welded element of excavator fittings. Calculations were made according to four criteria of multiaxial random fatigue. Cycles were counted with the rainflow method, and damage was cumulated with the Palmgren-Miner hypothesis. It was found that convariances of random stress state components strongly influence the calculated fatigue li…