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Structural behavior of the old masonry bridge in the Gulf of Castellammare
No full textMasonry arch bridges represent a very significant part of the heritage of road and railway artworks all over the word and especially in the Mediterranean area, both in terms of: numbers; reduced environmental impact; and static efficiency. In these cases, the cost of maintenance is often limited to the content and channeling of surface water and control of vegetation, which can eventually take root on the joints of the masonry at the shoulders. In masonry bridges, there are no expansion joints or hinges with support equipment or trolleys, as in metal bridges and reinforced concrete ones, or paint, or resin surface protection, all items that affect the cost of maintenance. The permanent weight of these bridges is very high and, together with the mechanical characteristics of the structure, results in very high strength and stiffness against moving loads. This is one of the most valuable aspects of masonry arch bridges, making it possible to keep open to traffic safely, without repair actions, bridges that are centuries old and which are now subject to vehicular traffic and trains producing actions that are considerably higher than those for which they were originally designed.The purpose of this work was a static check on the old Gate Bridge, a road bridge in masonry which links Corso Garibaldi and Via Giacomo Puccini in the town of Castellammare del Golfo (Trapani province). An extensive experimental research was carried out for in situ mechanical characterization of the constituent materials and static tests were also carried out to study the structural response (load-deflection curves) of the arch bridge. Finally, analytical and numerical analyses were carried out for safety verification of the arch stone and for verification of the serviceability condition. © 2015
In-situ NDT testing procedure as an integral part of failure analysis of historical masonry arch bridges
No full textA nineteenth-century masonry arch bridge was analyzed as an illustrative example to explain the role of in-situ test campaigns in failure analysis and retrofit design. Test results were studied to find out the advantages of each technique, with the aim of proposing an optimized in-situ testing procedure. Standard static penetrometer, flat jack, thermographic and georadar in-situ tests were conducted. Traffic effects were analyzed by means of vibrational tests. The experimental analysis performed to investigate damage on the bridge structures shows the degree of reliability offered by each technique in evaluating specific information and reproducing the global behavior of the structure
Retrofitting a Short Span Bridge with a Semi-Integral Abutment Bridge: The Treviso Bridge
No full textThere are a number of bridges which are designed according to codes without seismic provisions being considered. Such bridges are mostly found deficient and may need seismic retrofitting. Bridges that were built before the 1970 S, either in the USA or Japan or Europe, were designed with little or no consideration for seismic demands. The majority of these bridges are supported on reinforced concrete bents at the abutments and pier walls that lack the ductility and strength to resist earthquakes. Besides most of these bridges have short spans (6-18 m) to medium spans (18-90 m). A bridge with a short span may be built with timber girders or with a concrete slab superstructure, whereas a bridge with a medium span is often built with steel girders, precast concrete girders, or cast-in-place box girders. Bridges in general consist of two structural components: a superstructure including the elements above the support and a substructure including the elements that sustain the superstructure. In this paper, the retrofitting of an existing short bridge is discussed; it is situated in Treviso (a town in the Venice area) near the vital new airport "Antonio Canova". Retrofit consists of building a new semi-integral bridge type with micro-piers on the bridge heads
"Dolcèviaduct": Pier seismic analysis with the Italian code and Euro-Codes ["Il viadotto di Dolcè": Analisi sismica delle pile secondo la normativa italiana e l'Eurocodice]
No full textDamages due to seismic action on bridges are a direct consequence of the elastic approach of their design. The introduction of the new seismic norm in Italy and in the world have prescribed a ductile behavior for the piers subjected to action of earthquake. The bridge design based on a ductile behaviour of piers uses the formation of plastic hinges to reduce seismic action by dissipation of energy. The design of the "Dolcè"Viaduct, an important bridge of next realization in Verona area. This viaduct has medium span and composite structure steel-concrete, for it is evaluated the different security level and ductility of the seismic response depending on the configurations of the piers. The study takes into account the Euro-codes and the Italian norm
Testing of “Global Young's Modulus E” on a rehabilitated masonry bell tower in Venice
No full textThis 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 masonry bell tower. Rayleigh's method, using as input data the natural frequency obtained with an experimental accurate validation like the dynamic identification, was utilized to determine the global Young's modulus
Retrofit with FRP elements and seismic performence assessment of the historic "Castagnara" Bridge in Padua, Italy
No full textThe paper deals with the application to "Castagnara" masonry bridge in Padua, Italy of an originally developed methodology to retrofit and repair. In this paper the investigations related to the damage of the bridge, the retrofit by FRP elements and the results of the consolidation are shown. A non-linear analysis of the bridge has been performed to see the effective benefits due to the retrofit
THE SYMPTOM MANAGEMENT MODEL(SMS) TOOL FOR PREDICTION AND ASSESSMENT OF CERTAIN SYMPTOMS THAT AFFECT QUALITY OF LIFE OF PATIENTS WITH SMALL AND NON SMALL CELL LUNG CANCER CANDIDATES FOR RADIOCHEMOTHERAPY
No full textSeismic assessment of a venetian bell tower taking into account soil-structure interaction
No full textThe paper gives a preliminary insight into the seismic vulnerability of bell towers, discussing a real case study, namely a masonry tower built in XIX century and located in the Province of Venice (Italy). Such a case study is fully investigated using different advanced FE strategies. The case study shows structural features often common in other cases, such as the foundation rotation due to soft soils, which causes the tower to lean. Both these parameters, the soil-structure interaction and the inclination, are expected to play a crucial role in the dynamic response and the lateral bearing capacity reduction. The present literature suggests different approaches to model and to account for such parameters, whereas technical codes mostly seem to propose simplified procedures that result in an underestimation of the real effect. The role of the soil is observed to be crucial in the shape and excited mass changes of the natural modes, thus implicitly modifying the seismic response. Furthermore, in general, the out-of-verticality of a tower causes the concentration of the vertical stresses and a significant capacity drop. In the present paper, different FE simulations are performed in order to investigate the actual dynamic behavior of the tower under study, to be compared with standard modeling used for bell towers
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