Indagine sperimentale su nodi di tralicci in acciaio di travi reticolari miste

Results of experimental tests on welded joints of steel truss of encased composite steel-concrete beams are presented. The welding of the inclined web bars to top bars, both of steel type B450C, and to bottom steel plate, the latter made of S355 steel type, are tested. Two analytical expressions for prediction of welding strength are derived: the one based on a resistance criterion and the other based on a limit domain of the welding section. Guidelines for choosing the effective dimensions of the fillet weld, necessary to determine the strength, are provided. A high precision digital scanner is used to validate the suggested guidelines to determine the geometrical characteristics of the fi…

Travi reticolari miste- Problemi locali nella trasmissione degli sforzi

Experimental test results on the local behavior of the typical Italian typology of hybrid steel-to-concrete beam are presented and discussed in order to provide insight on transfer mechanism between different components of the beam. Preliminarily, in order to investigate on the bearing capacity of the welding and on the local instability problems that can arise in the trusses before concrete casting, tensile tests on specimens reproducing different types of welded joints, and push-out tests on bare specimen have been performed. Then, the transfer mechanism between steel trusses and concrete is investigated by means of push-out tests carried out also in displacement controlled mode. Results …

Retrofitting of Existing Steel MR-Frames by Encasing the Columns

Summary The study concerns the behaviour of steel MR-frames subjected to vertical and lateral forces, not properly designed according to capacity design criteria, and upgraded by means of encasing the steel columns with concrete having different grade. The purpose of the paper is to examine if the proposed technique allows one to adequately increase the lateral stiffness and the resistance of the frames. Pushover analyses on multi-storey frames are performed trough a non-linear calculus program, able to take into account of the second order effects. The behaviour of frames with encased columns was compared with those of the bare frames, highlighting that with the proposed technique it is po…

Indagine sperimentale sul comportamento di travi reticolari miste

Nel lavoro sono presentati i risultati di indagini sperimentali condotte su travi ed elementi di travi reticolari miste in acciaio-calcestruzzo, svolte presso l’Università di Palermo, nell’ambito di un programma di ricerca tendente a validare criteri e metodi per la progettazione strutturale di tali sistemi. Preliminarmente si riporta una sintesi dei risultati, già presentati in altre memorie, ottenuti da indagini su problemi locali di trasmissione degli sforzi tra gli elementi che compongono la trave sia prima che dopo il getto di calcestruzzo; successivamente si presentano i risultati di una sperimentazione su trave continua opportunamente strumentata in modo da rilevare il comportamento …

Behavior of fiber reinforced concrete-filled tubular columns in compression

Experimental compression tests on steel tubular columns filled with plain concrete and fiber reinforced concrete are carried out. For each type of column three different lengths are considered in order to point out the influence of slenderness on the ductility in compression. The experimental investigations presented here have emphasized the improvement in ductility capacity obtained when fiber reinforced concrete is utilised instead of plain concrete. Moreover, the results obtained stress that the lateral displacements due to global instability are drastically reduced.

COMPRESSIVE BEHAVIOR OF LAMINATED GLASS COLUMNS

This paper examines the behavior in compression of glass columns having tee (T) transverse cross-sections. The work highlights the issues recurring in the design of glass columns in rapid diffusion in the transparent architecture such as: - flexural and torsional buckling; - long-term effects and effects related to the temperature; - glued connections between single panels. In the work expressions are given for the calculation of the loadcarrying capacity of columns. The cases of full connection and absence of connection between the panels are analyzed and discussed. The comparison between the analytical and the experimental results highlights that in the case of glass columns with T cross-…

Compressive behaviour of laminated structural glass members

Abstract Several experimental investigations in the past few years have highlighted the fact that the compressive strength of glass was significantly higher than its tensile strength, allowing new applications of glass in compression members. However, due to the high slenderness of structural glass elements made of thin glass panels, they tend to fail in a brittle manner. A substantial amount of fundamental research has been carried out in the past few years to investigate the stability behaviour of structural glass elements. However, although buckling of glass panels has been quite well studied, a very poor amount of research has been addressed to glass columns, which by contrast represent…

L'acciaio nel restauro del Convento di S. Agostino a Corleone (PA)

The paper describes the techniques adopted for the static and seismic retrofitting of the S. Agostino Convent in Corleone (PA), which is classified as II category seismic zone in the Italian Code. In this work many maintenances have been conducted with the use of inox steel and carbon steel. The main works consist in new decks, built with steel - concrete system, a new stair, two elevators and interventions in the masonry active ties with the use of stainless steel ribbons. This last method is named C.A.M.. A lot of details of the verification criteria and of the constructive solutions are showed.

Il recupero parziale di opere in muratura di interesse storico in zona sismica

Un metodo per il progetto di massima di dissipatori isteretici e viscosi e applicazione a casi concreti

Isolamento sismico di un serbatoio a Priolo Gargallo (SR)

The paper relates the operations made for the seismic isolation of a tank located in Priolo Gargallo, in the Siracusa industrial area. The tank, built during the end of the seventies, is formed by a cylindrical steel shell, filled by a low temperature liquid, rested on a concrete slab, embedded on 139 columns, fitted together with the same number of foundation piles driven in the soil for about 12 meters. The friction pendulum bearing seismic devices have been adopted, installed in the superior part of the columns through the cut of a small section of the same. The intervention foresees the execution of a concrete slab at grade level, which has the functions to link all the pile heads, to f…

Seismic response of steel frames with reduced beam sections

This study concerns the effectiveness of weakening on the beams of fully and partially restrained connection steel frames in order to locate plastic hinges far from the joints. Two types of non-linear analysis, for geometry and constitutive law are developed: static pushover analysis, in which the structure is subjected to constant vertical loads and to horizontal loads linearly increasing up to collapse; and incremental dynamic analysis, in which the structure is subjected to uniformly scaled ground motions. Applications for four-bay frames with three and nine stories designed according to the EC3 code and for Italian 1st-category seismic areas are developed in order to evaluate the influe…

Nicolò Scibilia - una vita per le costruzioni 1945-1999

L’esposizione comprende un arco temporale di circa un quarantennio e traccia un quadro sufficientemente completo di Nicolò Scibilia, ingegnere progettista e imprenditore. La sua vasta attività comprende un primo periodo di circa dieci anni dedicato prevalentemente alla ricostruzione del paese distrutto dalla guerra. In tale ambito si collocano gli importanti interventi sulle chiese di S, Francesco d’Assisi e dell’Olivella gravemente danneggiate dai bombardamenti del 1943. Seguirono interventi di costruzione di nuovi edifici residenziali sulla base del Piano di Ricostruzione e di piani di lottizzazione. Ampio spazio è dedicato alle progettazioni per l'edilizia religiosa, scolastica e assiste…

Indagine sperimentale sul comportamento di pareti sismiche in acciaio sottoposte a taglio

The paper concerns the experimental results performed on steel (S 235) zinc plated panels having 1500 x 1150 x 1.5 mm dimensions, linked to hinged steel frame. In order to the slenderness of plates, considerable displacements out-of-plane are evident at loads significantly lower of ultimate load. Considering the steel constitutive curves obtained from tensile tests, the comparison of experimental and numerical (ADINA) results is proposed. The results show the excellent seismic behaviour of the system having stable hysteresis loops.

INDAGINI TEORICHE E SPERIMENTALI SU PARETI SISMICHE IN ACCIAIO

La memoria riguarda il comportamento di pannelli sottili in acciaio utilizzati come pareti di controvento. Per tali sistemi sono previsti due tipi fondamentali di utilizzo: come elementi dissipativi e irrigidenti;come elementi irrigidenti. Il primo caso riguarda pannelli dotati di robusti irrigidimenti, tali da determinare lo snervamento delle lastre costituenti il pannello prima dell’insorgere di fenomeni di instabilità. Tale tipologia è stata utilizzata prevalentemente in Giappone. La tendenza ad adottare pannelli sottili, per i quali l’instabilità avviene in campo elastico, si è sviluppata prevalentemente negli USA ed in Canada, ove attraverso indagini sperimentali si è constatato il not…

Isolamento sismico di serbatoi di impianti chimici a Priolo Gargallo (SR)

I serbatoi di stoccaggio degli impianti petrolchimici costituiscono una seria minaccia alla salvaguardia dell’ambiente, a causa delle conseguenze disastrose derivanti da un loro collasso, come messo in luce dai recenti eventi catastrofici. Pertanto, l’ENEA ed il GLIS hanno intrapreso un’intensa attività di ricerca e di informazione per sensibilizzare l’opinione pubblica su tali importanti pericoli. Tra le cause più frequenti di collasso si citano le azioni sismiche, particolarmente rilevanti in zone prossime a faglie attive, come risulta quella di Priolo Gargallo, in provincia di Siracusa, già sede di sismi distruttivi. I danni sono stati spesso ingigantiti dagli incendi sviluppatisi in seg…

Prove di Push-Out su travi reticolari miste

Results of push-out experimental tests on typical italian typology of hybrid steel-to-concrete beam are presented and discussed in order to provide insight on transfer mechanism between concrete and steel truss. Two specimens of a shallow beam are tested and experimental relationships between interaction force, total slip and strain in truss elements are shown; moreover, behaviour of specimens at failure is discussed.

Indagine sperimentale sul comportamento ciclico di pannelli sottili di controvento di telai in acciaio

The paper concerns the experimental results performed on steel (S 235) zinc plated panels having 1500 x 1150 x 1.5 mm dimensions, linked to hinged steel frame. In order to the slen-derness of plates, considerable displacements out-of-plane are evident at loads significantly lower of ultimate load. Considering the steel constitutive curves obtained from tensile tests, the comparison of experimental and numerical (ADINA) results is proposed. The results show the excellent seismic behaviour of the system having stable hysteresis loops.

Shear-to-Moment Interaction in Glass Beams with Open Cross Sections

An experimental investigation regarding the flexural behavior of glass beams with a length of 1,200 mm and rectangular, T-shaped, or I-shaped cross sections is presented and discussed. T-shaped and I-shaped cross sections were obtained by assembling laminated glass (LG) panels of 200 mm depth and 12.76 mm thickness through an acrylic adhesive. Three specimens for each series investigated were tested in flexure, focusing on the flexural and shear response of beams through the determination of the load-deflection curves and crack patterns at rupture. The shear span to depth ratio a/d was 2.25, which is a very low value, and interaction of shear and bending moment occurred during the tests. An…

LONG-TERM STRUCTURAL DEFICIENCIES IN A MAT FOUNDATION ON CLAY SOIL

A 3-story building with a mat foundation consisting of a slab on a grid of grade beams performed poorly on clay soil. Cracking of the slab became rogressively worse as a result of the incorrect esign and fluctuations in the groundwater pressure under the foundation. The cyclic presence and absence of water rusted the steel reinforcement, and the sulfates in the clay soil caused formation of ettringite in the concrete. Plastic hinges formed in the slab and settlements occurred, causing damage to the beams. The situation is still in progress and may lead to the collapse of the structure under normal service conditions. The geotechnical and structural investigations performed to survey and ass…

Behavior of beam-column concrete filled steel tubes with square and rectangular cross-section

COLONNE IN VETRO STRATIFICATO: CRITERI DI PROGETTAZIONE

This paper concerns the key aspects of the design of laminated glass structural elements subjected to axial forces of compression. An analysis of the Italian and European design-code frame is conducted with the analysis of experimental results reported in literature. The present study shown the existing of many problems in the implementation of these structural elements, such as a significant reduction of the theoretical value of compressive strength. Finally, we report the design process and the numerical analysis of laminated glass columns of a canopy prototype designed by the authors, starting by the definition of the loads and boundary conditions, the definition of the supporting struct…

Tecnica del sovracarotaggio per pilastri compressi in c.a.

The paper shows the results of an experimental investigation on the behaviour of compressed concrete columns subjected to the overcoring technique. Extraction of cylindrical concrete cores in perpendicular direction to the column surface, was achieved by rotary drilling using a diamond tipped hollow barrel. Core is gradually isolated from the stress field in the surrounding concrete and at every advancing step the re-equilibrium deformation response is measured by means of four strain-gauges, placed on its external surface and near the hole. Finally the original stress state is computed in the elastic phase on the basis of recorded strains, knowing the elastic properties of concrete and by …

Risposta sismica di edifici prefabbricati isolati con dispositivi elastomerici

The paper concerns the seismic behavior of precast concrete industrial buildings with an elevation equipped with seismic isolators. It’s examined a building with rectangular plan of m 40x 50. The structure is constituted of columns of square cross-section of 0.6 m, with continuum beams foundation. The desk is made with T section beams for each frame connected by Gerber joints in the main direction and they support precast pre-tensioned tiles with  shape. A plate of concrete is casted of the wing tiles for obtain a connected rigid deck. At the top of the pillars will be placed rubber bearings having high dissipation capacity (HDRB). The dynamic behavior of the structure under recorded real …

Experimental behavior of concrete filled-columns in compression

Coperture in vetro stratificato: criteri di progettazione

This paper concerns the design activity about laminated glass structures for the evaluation of criteria to optimize the design. This target is reached by using a preliminary study of the normative frame in national and international field. Forward by studying the bibliography on laminated glass structure. Application is on canopy designed by authors. Here are reported the step design procedures starting by definition of load, the restraints condition for structure element and a 3d model is produced by using a FEM method.

INDAGINE SPERIMENTALE SU ELEMENTI IN VETRO STRUTTURALE COMPRESSI

Several experimental investigations in the past few years have highlighted the fact that the compressive strength of glass was significantly higher than its tensile strength, allowing new applications of glass in compression members. However, due to the high slenderness of structural glass elements made of thin glass panels, they tend to fail in a brittle manner. A substantial amount of fundamental research has been carried out in the past few years to investigate the stability behaviour of structural glass elements. However, although buckling of glass panels has been quite well studied, a very poor amount of research has been addressed to glass columns, which by contrast represent the most…

A innovative laterals hydro floating tilting systems for USV or surface nautical vehicles

The proposed project shows the results obtained in the implementation and testing in lacustrine and marine environment of an innovative laterals hydro floating tilting systems control for USV or remote/autonomous surface nautical vehicles. This vehicle is based on a pending patent belonging to Palermo University (Patent Pending RM2012A000209 and RM2012A000209). The system allows, during operation as a vehicle USV, set changes sailing trim and make turns with very narrow angle with little shunting movements. In fact the main benefits obtained were able to change or adjust the navigation structure by changing the tilt of one or two hydro floating during navigation without intervening directly…

TELAI DISSIPATIVI IN ACCIAIO PER LA MITIGAZIONE DEL RISCHIO SISMICO DI SISTEMI MURARI DI INTERESSE STORICO

Il lavoro riguarda la possibilità di impiego di dispositivi fluido viscosi per il miglioramento o l’adeguamento sismico di edifici in muratura appartenenti all’edilizia storico monumentale. In questi casi, per evidenti motivi legati alla tutela dei valori architettonici dell’opera, non è possibile adottare interventi di tipo tradizionale per il rinforzo statico della muratura (FRP, CAM). Una soluzione alternativa, di maggiore efficacia, può essere ottenuta attraverso l’inserimento di dispositivi fluido viscosi, con il risultato di aumentare la capacità dissipativa della struttura con conseguente riduzione della domanda di spostamento. A riguardo, si descrive una procedura, già proposta da a…

Footbridge design in Viale Regione Siciliana in Palermo

The paper investigates some solutions designed by the author, as structural consulting engineer of the municipal administration of Palermo, to build a footbridge over Viale Regione Siciliana, in the section between Via Perpignano and Viale Leonardo Da Vinci. The pedestrian underpass put in place in the 1990s, during the construction of the new road, was considered to be unsatisfactory for pedestrian safety due to possible robberies. In the last few years the administration has been oriented towards the creation of footbridges, designed to be accessible to the differently abled too. This is possible in relationship to the definitive abandonment of the project of a flyover. The paper shows so…

Flexural behavior of laminated glass beams with T cross-sections

INTERVENTI STRUTTURALI PER L'ADEGUAMENTO DEL TEATRO MASSIMO DI PALERMO

La nota riferisce su alcuni interventi strutturali eseguiti nel corso dei lavori di ristrutturazione del Teatro Massimo Vittorio Emanuele di Palermo, per adeguarlo alle nuove esigenze sceniche e impiantistiche. Dopo una sintetica descrizione delle caratteristiche costruttive dell’edificio e di alcune soluzioni tecniche adottate da Giovan Battista Filippo Basile nel corso della costruzione, si descrivono le vicende e le opere legate agli interventi sul palcoscenico, sulle torri quadrangolari adiacenti, sulla copertura del pronao e per l’utilizzo della sala sottocupola. Si prendono in considerazione aspetti legati alla resistenza delle murature e del terreno di fondazione ed al progetto delle…

Influence of concrete cover on the compressive strength of fiber reinforced concrete columns

The paper focuses on the influence of the concrete cover on the strength of confined compressed columns made of fiber reinforced concrete. A mechanical model has been developed based on the ultimate state conditions of concrete core, concrete cover and transverse steel. The cases of plain concrete and fiber reinforced concrete are analysed and focus on the beneficial effects due to the presence of fibers. The model has been verified against data obtained from concentric compressive tests on concrete specimens reinforced with transverse steel and fibers.

Upgrading of existing steel MR-frames by encasing the columns

INTERVENTI DI MIGLIORAMENTO SISMICO DEL PALAZZO BONAGIA DI PALERMO

La memoria riguarda gli interventi progettati per la ricostruzione del Palazzo Bonagia sito in Via Alloro, nel centro storico di Palermo, che costituisce uno degli edifici più significativi dell’architettura civile tardo barocca siciliana e testimonia dei terribili danni inferti alla città dai bombardamenti del 1943, dall’incuria dei proprietari nel mantenere in vita le parti risparmiate dalla guerra e degli atti di vandalismo di cui sono stati oggetto un gran numero di monumenti. Nei primi anni del Settecento iniziò l'opera di successive aquisizioni di immobili, che vennero poi riuniti e riconfigurati attraverso un progetto unitario. La realizzazione del nuovo edificio venne commissionata …

Indagine sperimentale su travi in calcestruzzo fibroso sottoposte a carichi monotonici e ciclici

COMPORTAMENTO DI IMPALCATI DA PONTE A CASSONE IN ACCIAIO-CALCESTRUZZO CON ANIMA ONDULATA

La memoria riguarda il comportamento di un impalcato di ponte stradale a cassone avente le anime sagomate secondo una sinusoide, con soletta in c.a. collaborante. L'impalcato presenta schema statico longitudinale di trave continua su 4 appoggi. The paper concerns the behaviour of a box-girder bridge deck road having a steel box and a concrete slab. The steel webs are shaped according to a sine wave. The deck has a width of 13.70 m and a length of 182 m, with the longitudinal static scheme as a continuous beam on four supports. The study highlights the reliability of this constructive solution.

Procedure esecutive in presenza di convogli eccezionali su ponti stradali privi di documenti progettuali

La presente nota riguarda le procedure adottate per verificare l'ammissibilità del transito di convogli eccezionali su quattro viadotti esistenti lungo la S.S. 640 Agrigento-Caltanissetta per il trasporto di componenti della Tunnel Boring Machine (TBM) per la realizzazione della nuova Galleria Caltanissetta. Si descrivono le ispezioni ed i rilievi effettuati al fine di determinare le caratteristiche geometriche delle opere d'arte, le indagini sui materiali al fine di caratterizzarne la resistenza. Inoltre, facendo riferimento alla normativa in vigore all'epoca di progettazione, si sono disposte prove di carico preliminari tali da indurre sollecitazioni prossime a quelle indotte dal transito…

Influenza del coefficiente di poisson sul comportamento in compressione di colonne composte acciaio-calcestruzzo a sezione circolare

In the paper an analytical model able to predict the whole compressive response of stub CFT subjected to uniaxial compression is presented and discussed. Cases examined re-ferred to member with circular cross-section having length 400 mm and diameter ranging be-tween 88.9 and 457 mm and wall thickness between 6 and 8 mm. Two steel grades of 275 and 460 MPa yielding stress were examined and four concrete grades were investigated (20, 28, 40 and 45 MPa). The proposed model take into account of the variable confined pressures exercised by steel wall on concrete core and of the biaxial state of stresses induced in steel wall. The model was verified both in term of load-shortening curves with da…

COMPORTAMENTO CICLICO DI PANNELLI SOTTILI IN ACCIAIO

abstractita La memoria riporta i risultati di indagini sperimentali su pareti sottili in acciaio sottoposte ad azioni cicliche, ponendo in risalto le capacità dissipative. Le prove sono state condotte presso il laboratorio DISMAT di Canicattì (AG)su modelli in scala 1:2. I risultati evidenziano le riserve di resistenza dei pannelli in fase post critica. Results of experimental tests on Steel Plate Shear Wall (SPSW) placed in steel frames subjected to cyclic actions are presented, stressing the dissipative capacity of the system. The tests were performed at the DISMAT laboratory in Canicattì (AG) on scale specimens. The surrounding frame is made by HEA 160 beam and columns with pinned joint,…

Strength and Ductility of Hollow Circular Steel Columns Filled with Fibre Reinforced Concrete

Publisher Summary This chapter investigates the behavior of hollow circular steel cross-sections filled with Fiber Reinforced Concrete (FRC), subjected to monotonic loads. The casting of different types of composite members—steel columns, steel columns filled with Normal Strength Concrete (NSC), and steel columns filled with Fiber Reinforced Concrete (FRC) was employed. The columns were tested in uniaxial compression utilizing a universal testing machine operating in displacement control. The maximum strength of composite members filled with FRC was 20% higher than that recorded for steel pipes filled with FRC. After the peak load was reached, failure was due to the crushing of concrete and…

TRAVI CONTINUE IN ACCIAIO CON ANIMA ONDULATA PER IMPALCATI MISTI IN ACCIAIO CALCESTRUZZO

La memoria riguarda gli impalcati per ponti stradali con travi in acciaio saldate, aventi l’anima sagomata secondo una sinusoide e soletta in c.a. collaborante. L’attenzione è focalizzata su impalcati aventi schema statico longitudinale di trave continua su 4 appoggi, costituiti da due sole travi in acciaio, e da una soletta in c.a.. Il progetto è sviluppato per un ponte stradale di I categoria, avente larghezza di 12.10 m e lungo 182 m. Lo studio consente di confrontare le soluzioni costruttive rappresentate da travi con anima tradizionale piana o sinusoidale e di porre in luce alcuni vantaggi di tale ultimo sistema.

VALUTAZIONE DELLA RESISTENZA IN SITU DEI CALCESTRUZZI STRUTTURALI

La memoria riguarda la valutazione della resistenza in situ dei calcestruzzi e riveste notevole importanza per giudicare la sicurezza e la durabilità delle strutture in cemento armato. Essa riporta alcuni criteri di valutazione della resistenza in situ dei calcestruzzi strutturali che è possibile determinare a posteriori attraverso prove di compressione su provini cilindrici ricavati da carote estratte dalle strutture da esaminare. Si evidenziano i principali fattori che influenzano i risultati delle prove di laboratorio e come questi vadano interpretati per la determinazione più attendibile della resistenza in situ dell’opera. Con riferimento ad indagini riguardanti opere realizzate in Sic…

MASS-PRODUCED ELEMENT IN STRUCTURAL GLASS: “ARTIFICIAL VINEYARD”

The aim is to design an architectural element flexible and easily adaptable to different urban situations using a material such as glass that, for the last years, is being employed as a structural element. The mass-production is rarely applied to glass construction systems that instead are usually designed case by case. The paper reports the results of a research carried out by the Dipartmento di Architettura and Dipartimento DICAM (Dipartimento di Ingegneria Civile, Ambientale, Aerospaziale, dei Materiali), of the University of Palermo, within the project "VESTRA" (POFESR 2007/2013 - Action Line 4.1.1.1), that aims to the experimentation of mass-produced elements in structural glass. The p…

Some recent results on the compressive and flexural behaviour of composite members

Experiemntal results from compression and flexural tests on steel tubulare columns having circular or rectangular transverse cross-section and infilled with plain or fiber reinforced concrete (FRC) are analysez. for composite members differenti lengths and different dimensions of transverse cross-section were considered in order to assess the influence on behavior in flexure and in compression.The fiber investigated with different percentage were syntetic, carbon and deformed steel fibers. The constituent materials were characterised through compressive and split tests on conconcrete cylinders. Load.shortning and load-delection curves were determined including the sotnening response. Simpli…

PIETRO SCIBILIA Ingegnere Architetto (1889-1971)

Il volume analizza l’attività professionale di Pietro Scibilia (1889-1971), architetto e ingegnere palermitano che opera nell’arco temporale compreso fra gli anni venti e gli anni sessanta del Novecento, comparandone la produzione progettuale con il coevo panorama locale e nazionale. La ricerca, raccontata attraverso l’analisi dei suoi progetti e della sua vasta produzione architettonica, si è basata in primo luogo sullo studio del fondo documentario costituente l’archivio Scibilia, ed è stata supportata da un’indagine incrociata svolta anche presso altri archivi siciliani, primo fra tutti l’Archivio Storico del Comune di Palermo, che si è rivelato una fonte di primaria importanza per il re…

Interventi migliorativi in acciaio a tutela delle opere di interesse storico-monumentale dal rischio sismico

The research concerns the analysis of structural behaviour of some historic-monumental buildings in which steel structures are used for the seismic protection. A dynamic model has been made to individuate the macro-element with an high seismic risk, that is, for church studied, the drum-dome system. Then a scaled model has been tested to determinate the evolution of the lesions, the retrofitting works, that are constituted by steel frames, bare or braced, inserted inside door/window holes of the drum-dome system, and the variation structural ductility. An elastic linear analysis, with a FEM software, has been developed for other type of buildings, in which the vertical structures are made w…

Interventi di miglioramento e adeguamento sismico di edifici in c.a. dell’Azienda Ospedaliera Universitaria Policlinico “Paolo Giaccone” di Palermo

The paper shows the results of an experimental investigation on the behaviour of compressed concrete columns subjected to the overcoring technique. Extraction of cylindrical concrete cores in perpendicular direction to the column surface, was achieved by rotary drilling using a diamond tipped hollow barrel. Core is gradually isolated from the stress field in the surrounding concrete and at every advancing step the re-equilibrium deformation response is measured by means of four strain-gauges, placed on its external surface and near the hole. Finally the original stress state is computed in the elastic phase on the basis of recorded strains, knowing the elastic properties of concrete and by …

Progetto di Strutture in acciaio per le nuove costruzioni e per gli interventi di consolidamento. IV Edizione

The book is a state of the art summary of recent development in the behavior, analysis and design of steel and composite structures. The book provides advanced students, researchers al professionals in civil and structural engineering with the basic principles upon which the modern codes are based. In the first part, the materials, the actions and the sectional behavior are analyzed on the base of the limit state theory. Then the connections (bolted and welded)and the stability effects are examined. In this way is possible speak about seismic performance, retrofitting an refurbishment of existing buildings, referring to the italian rules, to the european codes EC3, EC4 and to the AISC rules.