Search results for "Structural engineering"
showing 10 items of 1998 documents
Evaluation of infilled frames: an updated in-plane-stiffness macro-model considering the effects of vertical loads
2015
The influence of masonry infills on the in-plane behaviour of RC framed structures is a central topic in the seismic evaluation and retrofitting of existing buildings. Many models in the literature use an equivalent strut member in order to represent the infill but, among the parameters influencing the equivalent strut behaviour, the effect of vertical loads acting on the frames is recognized but not quantified. Nevertheless a vertical load causes a non-negligible variation in the in-plane behaviour of infilled frames by influencing the effective volume of the infill. This results in a change in the stiffness and strength of the system. This paper presents an equivalent diagonal pin-jointed…
FE Calculation Methodology for the Thermodynamic Fatigue Analysis of an Engine Component
2006
Thermo mechanical fatigue problem is treated to define an analysis methodology permitting the strength evaluation by reliability viewpoint. The main difficulty is the lack of both theoretical and experimental information; consequently the problem is treated verifying continually the validity and the limits of the developing solution method. The main task of the activity described in this paper was the development of a numerical methodology, based on FE analyses, for the evaluation of the structural behavior of engine components subjected to thermo mechanical fatigue phenomena. The chosen application was the exhaust manifold of an IC engine; FE analyses were executed following the standard m…
Experimental validation of a direct pre-design formula for TLCD
2014
The passive control of vibrations has received in recent years a great deal of attention from researchers. Several types of devices have been proposed in order to reduce the dynamic responses of different kinds of structural systems. Among them, the Tuned Liquid Column Damper (TLCD) has proved to be very effective in reducing vibration of structures. However, since the equations governing the TLCD controlled systems response is nonlinear, the calibration of TLCD parameters is time consuming and not convenient to perform in a pre-design phase. In this context, it has recently been introduced by the authors a formula that allows to choose the optimal parameters of TLCD in a direct and fast wa…
Use of finite element models for estimating thermal performance of façade-integrated solar thermal collectors
2016
Abstract Research on building-integrated solar thermal collectors is attracting increasingly more interest. Many efforts have been focused at the design level for obtaining specific building-orientated products, but there is a significant lack of standardised methods for evaluating how the efficiency of solar collectors changes when a wall is an integral part of the solar component itself. Generally speaking, experimental tests on integrated components are not easy to realise and are, in any case, expensive in terms of time and money. Physical and numerical methods can be utilised, but at the moment, there is no common approach. The present work addresses a method for the calculation of a b…
Using FEM simulation to predict structural performances of a sailing dinghy
2017
The use of finite element method (FEM) tools is proposed to investigate the structural response of an eco-sustainable sailing yacht to different loading conditions, typical of those acting during regattas. The boat is, in particular, a 4.60 m dinghy with the hull and the deck made of an hybrid flaxâcork sandwich and internal reinforcements made of marine plywood. A preliminary activity has consisted in the refitting of an existing model in order to reduce the hull weight and to improve performances during manoeuvrings. These tasks have been interactively simulated in the virtual environment of the boat CAD model, where longitudinal and transversal reinforcements were enlightened and the m…
Thermal stress analysis of different full and ventilated disc brakes
2015
During the braking phase, the heat produced by friction between pads and disc cannot be entirely dissipated. Consequently, the brake disc, especially if very hard braking occur, can accumulate large amounts of heat in a short time so producing high gradients of temperature on it. Under these conditions, functionality and safety of the brake system can be compromised. The object of this study is to investigate, under extreme working conditions, the thermomechanical behaviour of different brake rotors in order to evaluate their efficiency and stability and to identify any compromising weakness on them. In particular, by means of FEM thermo-mechanical coupled analyses, one full disc and three …
Rotor-bar breakage mechanism and prognosis in an induction motor
2015
© 1982-2012 IEEE. This paper proposes a condition-based maintenance and prognostics and health management (CBM/PHM) procedure for a rotor bar in an induction motor. The methodology is based on the results of a fatigue test intended to reproduce in the most natural way a bar breakage in order to carry out a comparison between transient and stationary diagnosis methods for incipient fault detection. Newly developed techniques in stator-current transient analysis have allowed tracking the developing fault during the last part of the test, identifying the failure mechanism, and establishing a physical model of the process. This nonlinear failure model is integrated in a particle filtering algor…
Field Testing of a Simple Flume (SMBF) for Flow Measurement in Open Channels
2008
In this paper the stage–discharge relationship of a new flume named SMBF (Samani, Magallanex, Baiamonte, Ferro), originally proposed by Samani and Magallanez and tested by Baiamonte and Ferro, for measuring flow discharge in open channels is reviewed. The flume is obtained inserting two semicylinders in a rectangular cross section. The results of some experimental runs carried out using horizontal flumes characterized by different values of the contraction ratio (ranging from 0.17 to 0.81) are used for determining the two coefficients of the power stage–discharge equation. The stage–discharge equation is tested using flow measurements carried out in the period between December 2004 and Marc…
Capacity and safety analysis of hard-shoulder running (HSR). A motorway case study
2016
Abstract Operational motorway conditions can be improved by introducing traffic flow management and control systems, such as ramp metering (RM), high occupancy vehicle (HOV) lanes, real-time variable speed limits (VSLs), reversible lanes (RL), automated highway systems (AHS) and hard-shoulder running (HSR). The effects of such devices need to be examined in terms of capacity and safety. This paper examines the case study of the Italian motorway A22, which is supposed to be equipped with an HSR system implemented along 128 km in order to reduce congestion with consequent improvement in levels of service (LOS). We studied the traffic processes (capacity, flow distribution between lanes, relia…
Estimation of air pollutant emissions in flower roundabouts and in conventional roundabouts
2013
Abstract The road pollutant emissions, above all in urban context, are correlated to many infrastructural parameters and to traffic intensity and typology. The research work on road junction geometry, carried out in European research centres, has recently allowed to design new road intersection types which are of undoubted interest, especially in terms of traffic functionality and safety, like the flower roundabouts (in which right-turn manoeuvres do not conflict with the circulating flow). The main objective of this paper is to propose a model for the estimation the capacity, delay, levels of service and the pollutant emissions into flower roundabouts. A comparative analysis between conven…