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fabrizio paolacci

Assistant Professor

Graduated in Civil Engineering in 1992 at the University of Rome "La Sapienza" and Ph.D. in Structural Engineering in 1997, He is currently Assistant Professor in Structural Engineering at Roma Tre university – Department of Engineering. His main scientific interests are focused mainly...
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experience

Assistant Professor  
Università degli Studi Roma Tre, January 2005 to Present

Tecnica delle Costruzioni Structural Engineering

engineer in chief  
Università degli Studi Roma Tre, November 2000 to December 2004

technical and scientific responsible of experimental activities of the structural laboratory of the Departennt of Structures

Researcher  
University of Rome "La Sapienza", January 1998 to November 2000

Reserach grants for simulations of non-linear behaviour of structures equipped with dissipative devices

education

Università degli Studi di Roma 'La Sapienza'  
PhD, Structural Engineering, Jan, 1994 to Jan, 1997
Civil Engineering

Università degli Studi di Roma 'La Sapienza'  
laurea quinquennale, civil engineering, Jan, 1992 to Jan, 1992


projects

SEQBRI - PERFORMANCE-BASED EARTHQUAKE ENGINEERING ANALYSIS OF SHORT-MEDIUM SPAN STEEL-CONCRETE COMPO  by  fabrizio paolacci, University of Trento, University of Aachen, ArcelorMittal, SETRA, DOMI SA    
July, 2012 - Present
Nowadays, short-medium span steel-concrete composite I-girder bridges made of hot rolled steel beams are very popular, owing to their short construction time and reduced costs. Moreover, they are very adequate for seismic areas for their limited weight. With regard to static loading, these bridges can be designed based on recent Guidelines; however, seismic loading has not been yet investigated, and thus, they may exhibit damages even in low-seismicity zones. SEQBRI aims at applying the PBEE methodology to these bridges with S355M/N-S460M/N fine grain steels, to provide the foundation for a new generation of European seismic codes and to extend EN1998-1 and EN1998-2. Coordination: Fabrizio Paolacci

Assessment of the seismic vulnerability of an old r.c viaduct with frame piers and study of the effe  by  fabrizio paolacci, Luigi Di Sarno, Oreste S. Bursi, Giuseppe Abbiati, Cem Yenidogan, Mustafa Erdik, Raffele Derisi, Arkam Mohamad, Rosario Ceravolo, Luca Zanotti Fragonara, Daniele Corritore, Agostino    
January, 2012 - Present
The proposal aims to study the seismic behaviour of existing reinforced concrete (RC) bridges together with the analysis of the effectiveness of innovative and traditional retrofitting systems. The attention will be paid on old bridges generally not properly designed for seismic action. In particular viaducts with frame piers will be analyzed because of their high seismic vulnerability. On the basis of a previous experimental campaign consisting of cyclically imposed displacements on 1:4 reduced scale models of a frame pier belonging to a typical old RC highway viaduct, a new experimental activity is proposed. Two specimens (scale 1:2), a frame pier of 2 levels (height ≅7.5 m) and a frame pier of 3 levels (height ≅ 12.5 m), will be constructed and tested using the PsD technique with sub-structuring, which includes the modelling of the entire viaduct to which they belong. Asynchronous ground motion effects will be taken into account. Several test configurations will be considered: 1) a retrofitted viaduct using two isolation systems (Lead Rubber Bearings - LRB, Spherical Sliding Bearings -SSB) and 2) an “as-built” viaduct imposing a medium damage level. For each phase of the experimental campaign a proper dynamic identification will be performed. The aim is twofold: 1) increase the knowledge on the non-linear behaviour of RC frame piers details in presence of plain steel bars on which few studies have been conducted and 2) study the effectiveness of seismic isolation systems. Coordination: Fabrizio Paolacci

European Research Project: Structural safety of industrial steel tanks, pressure vessels and piping  by  fabrizio paolacci, Md Shahin Reza, Benno Hoffmeister, Nol Gresnigt, Kumar Anil, private private    
September, 2009 - Present
The INDUSE project aimed at developing design guidelines/recommendations for safeguarding structural integrity of industrial equipment steel structures, namely industrial tanks, pressure vessels and piping, under strong seismic action. The work combines structural seismic engineering concepts with mechanical engineering practice, considering the particularities of industrial systems and their support structures (shape and geometry, high internal pressure, interaction with liquid containment and the supporting structural system, material defects and damages that reduce significantly deformation capacity). Coordination: Spyros Karamanos

European Union Research Project: Seismic Engineering Research Infrastructures for European Synergies  by  fabrizio paolacci, Md Shahin Reza, Oreste S Bursi, Giuseppe Abbiati    
September, 2009 - Present
European seismic engineering research suffers from extreme fragmentation of research infrastructures (RI) between countries and limited access to them by the S/T community of earthquake engineering, especially that of Europe’s most seismic regions. A 23-strong consortium of the key actors in Europe’s seismic engineering research (including 3 industrial beneficiaries) addresses these problems in a sustainable way via a 4-year programme of activities at an annual cost to the EC less than 1.35% of the total present value (€190m) of the RIs’ material resources. The scope covers all aspects of seismic engineering testing, from eight reaction wall pseudodynamic (PsD) facilities and ten shake table labs, to EU’s unique tester of bearings or isolators, its two major centrifuges and an instrumented site for wave propagation studies.

INDUSE-2-SAFETY: Component fragility evaluation, seismic safety assessment and design of petrochemic  by  fabrizio paolacci, Md Shahin Reza, Oreste S. Bursi, Spyros A. Karamanos, Benno Hoffmeister    
December, 2013 - Present
INDUSE-2-SAFETY aims at developing a quantitative risk assessment methodology for seismic loss prevention of “special risk” petrochemical plants and components, e.g., support structures, piping systems, tanks and pressure vessels, flange and tee joints, etc. The proposed probabilistic based methodology will ensure safe functioning/shutdown under ground motions of increasing spectral acceleration through extensive analytical, FE and experimental investigations. Related harmonized importance factors γI and limit state probabilities will provide a uniform hazard versus a uniform risk basis for EN 1990/EN 1998. Coordinator: Oreste S. Bursi

publications

Experimental investigation on the seismic response of a steel liquid storage tank equipped with floa     
Published by (Wiley InterScience)
Authors: fabrizio paolacci, De Angelis Maurizio, Renato Giannini.  Published August 14, 2010

In this paper, the effectiveness of the base isolation on steel storage tanks has been investigated through numerical models and then checked by shaking table tests on a reduced scale (1:14) model of a real steel tank, typically used in petrochemical plants. In the experimental campaign the floating roof has also been taken into account. The tests have been performed on the physical model both in fixed and isolated base configurations; in particular two alternative base isolation systems have been used: high-damping rubber bearings devices and sliding isolators with elasto-plastic dampers. Finally, a comparison between experimental and numerical results has also been performed.

Seismic Reliability Assessment of a High-Voltage Disconnect Switch Using an Effective Fragility Anal     
Published by (Taylor and Francis group)
Authors: fabrizio paolacci, Renato Giannini.  Published February 02, 2009

This article deals with evaluation of the seismic vulnerability of a high-voltage vertical disconnect switch, one of the most vulnerable elements of electric substations. The main objective of the research is to evaluate the seismic fragility of the apparatus using a new effective method. By combining standard reliability methods for time-invariant problems with the response surface technique, this original procedure called “EFA” (Effective Fragility Analysis) permits the evaluation of fragility curves using a very limited number of numerical simulations. On the basis of experimental tests, to determine the mechanical characteristics of the disconnect switch components (ceramic, joints, etc.) the fragility curves of the equipment analyzed are carried out. The results are discussed and compared with the results of Monte Carlo simulations, which confirm the reliability of the procedure.

An experimental and numerical investigation on the cyclic response of a portal frame pier belonging     
Published by (Wiley & Sons)
Authors: fabrizio paolacci, Renato Giannini.  Published September 28, 2011

This paper deals with the assessment of the seismic response of a portal frame pier belonging to an old reinforced concrete viaduct. A series of tests, consisting of cyclically imposed displacements, were carried out on three 1:4 scale mock-ups. The objective of the experimental campaign is twofold: (1) identification and evaluation of the local failure mechanisms and (2) calibration of a numerical model including all observed nonlinear phenomena. The experimental results show that the shear strength of the transverse beam and of the beam–column joints characterizes the post-elastic behavior of the piers. Other phenomena, like bond-slip and buckling of the longitudinal bars of the columns, typical of old reinforced concrete structures have also been observed. Finally, a numerical model, built in OpenSEES, was calibrated to reproduce in a satisfactory way the experimental results and to provide a reliable tool for the evaluation of the seismic response of the pier.

Seismic Performance of Bolted flange Joints in Piping Systems for Oil and Gas Industries     
Published by (15th World Conference on Earthquake Engineering. Lisbon, Portugal, 24-28 September 2012.)
Authors: fabrizio paolacci, Md Shahin Reza, Oreste S. Bursi, Anil Kumar.  Published September 24, 2012

Recent seismic events showed a quite high vulnerability of industrial piping systems and components, wheredamage ranges from simple failure of joints to failure of supporting structures. The performance of the whole piping system strictly depends on the functionality of its individual components. Moreover, the behaviour of bolted joints is complex and critical under seismic actions. Therefore, they need special attention and deepinvestigation. In addition even for refinery industries, it is also important to know the leakage behaviour of typical flanged joints. Currently, both American and European codes are available to design flanged joints under static loading. Nonetheless, there is no code available to take into account seismic loading effects on these joints.Along these lines, we intend to present in this paper the results of a test campaign on two different types of flanged joints carried out at the University of Trento(Italy), by means of bending and axial loading, respectively.Test results were favourable and were analysed and compared with: 1) the demand provided by piping systemsconnected to a typical support structure, 2) allowable, yielding and ultimate design values provided by availablecodes

Seismic Performance of Bolted flange Joints in Piping Systems for Oil and Gas Industries     
Published by (15th World Conference on Earthquake Engineering. Lisbon, Portugal, 24-28 September 2012.)
Authors: fabrizio paolacci, Md Shahin Reza, Oreste S. Bursi, Anil Kumar.  Published September 24, 2012

Recent seismic events showed a quite high vulnerability of industrial piping systems and components, wheredamage ranges from simple failure of joints to failure of supporting structures. The performance of the whole piping system strictly depends on the functionality of its individual components. Moreover, the behaviour of bolted joints is complex and critical under seismic actions. Therefore, they need special attention and deepinvestigation. In addition even for refinery industries, it is also important to know the leakage behaviour of typical flanged joints. Currently, both American and European codes are available to design flanged joints under static loading. Nonetheless, there is no code available to take into account seismic loading effects on these joints.Along these lines, we intend to present in this paper the results of a test campaign on two different types of flanged joints carried out at the University of Trento(Italy), by means of bending and axial loading, respectively.Test results were favourable and were analysed and compared with: 1) the demand provided by piping systemsconnected to a typical support structure, 2) allowable, yielding and ultimate design values provided by available codes

Main Issues on the Seismic Design of Industrial Piping Systems and Components (in press)     
Published by (Proceedings of the ASME 2013 Pressure Vessels & Piping Division Conference, PVP 2013, July 14-18, 20)
Authors: fabrizio paolacci, Md Shahin Reza, Oreste S. Bursi, Nol Gresnigt, Anil Kumar.  Published May 26, 2011

A significant number of damages in piping systems and components during recent seismic events have been reported in literature which calls for a proper seismic design of these structures. Nevertheless, there exists an inadequacy of proper seismic analysis and design rules for a piping system and its components. Current seismic design codes are found to be over conservatives and some components, e.g., bolted flange joints, do not have any codes for their seismic design. Along this line, this paper discusses about the main issues on the seismic analysis and design of industrial piping systems and components. Initially, seismic analysis and component design of refinery piping systems are described. A review of current design approaches suggested by European (EN13480:3) and American (ASME B31.3) codes is performed through a case study on a piping system. Some limits of available codes are identified and a number of critical aspects of the problem e. g., dynamic interaction between pipes and rack, correct definition of the response factor and strain versus stress approach, are illustrated. Finally, results of experimental investigations carried out by the University of Trento, Italy on some bolted flange joints and on a piping system under earthquake loading are reported and discussed.

Seismic Analysis and Component Design of Refinery Piping Systems     
Published by (III ECCOMAS Thematic Conference on Computational Methods in Structural Dynamics and Earthquake Engin)
Authors: fabrizio paolacci, Md Shahin Reza, Oreste S. Bursi.  Published May 26, 2011

In petroleum industries, especially in refineries installations, hundreds of miles of pipes are installed to transfer row and refined material (fluid and gas) from a point to another of the plant, connecting all the components involved in the transformation process (tanks, distillations columns, furnaces, etc..).Recent seismic events showed a quite high vulnerability of these structures, where damage ranges from the simple failure of joints to the failure of supporting structures. For these reasons, initially the seismic analysis and component design of refinery piping systems is here analysed. A review of the current approaches imposed by European (EN13480:3) and American (ASME B31.3) standards is illustrated by using a proper case study of a piping system on a pipe-rack. The analysis permitted to identify the limits of the design standards and to identify the critical aspects of the problem, i.e., dynamic interaction between pipes and rack, correct definition of the response factor, strain versus stress approach. Finally, the preliminary phases of an experimental investigation on flanged joints are also illustrated.

Aftershock risk assessment and the decision to open traffic on bridges     
Published by (Earthquake Engng Struct. Dyn. / John Wiley and Sons)
Authors: fabrizio paolacci, Renato Giannini, fabrizio paolacci.  Published December 01, 2013

Critical issues in emergency management after a seismic event are assessing the functionality of the main infrastructures (hospitals, road network, etc.) and deciding on their usability just after the mainshock. The use of a pure analytical tool to assess the aftershock risk of a structure can be contrasted with the limited time available to make a decision about the usability of a structure. For this reason, this paper presents a method for evaluating post-earthquake bridge practicability based on a rational combination of information derived from numerical analyses and in situ inspections. In particular, we propose an effective tool to speed up the decision-making process involved in evaluating the seismic risk of mainshock-damaged bridges in the context of aftershocks. The risk is calculated by combining the aftershock hazard using the Omori law and the fragility curves of the structure, which are calculated using the regression analysis of a sample of results obtained with data randomly generated by the Latin Hypercube Sampling technique and updated based on the results of in situ inspection. Different decision criteria regarding the practicability of bridges are discussed, and a new criterion is proposed. This tool was applied to an old highway RC viaduct. There are two main findings, including the high sensitivity to Bayesian updating (especially when the damage predicted by numerical analysis does not match the real damage) and the criteria used to decide when re-open bridges to traffic.

Seismic response mitigation of chemical plant components by passive control techniques     
Published by (Journal of Loss Prevention in the Process Industries / Elesevier)
Authors: fabrizio paolacci, Renato Giannini, Maurizio Deangelis.  Published March 13, 2013

This paper deals with the applicability of seismic passive control in major-hazard chemical installations. The objective is to show numerically and experimentally the applicability of Passive Control Techniques (PCT) in industrial plants. Consequently, the main components of a process plant are classified and collected into a limited number of classes; for each class, the main damages caused by past earthquakes are described and the most vulnerable components are identified. A synthesis of the effects of earthquakes on the different typologies of process components is also presented and the most suitable innovative seismic protection systems, in particular passive control techniques (PCT), are acknowledged. Finally, the effectiveness of PCT in reducing the seismic response of process plant components is proved by three representative case studies: a base isolated above-ground storage tank, a distillation column connected by elastoplastic dampers to the adjacent service frame and an application of non-conventional Tuned Mass Dampers to a support frame.

An energy-based design for seismic resistant structures with viscoelastic dampers     
Published by (Earthquake and Structures / Technopress)
Authors: fabrizio paolacci.  Published April 01, 2013

The present paper aims at studying the seismic response of structures equipped with viscoelastic dampers (VED). The performance of such a passive control system is here analyzed using the energy balance concept, which leads to an optimal design process. The methodology is based on an energy index (EDI) whose maximization permits determination of the optimal mechanical characteristics of VED. On the basis of a single degree of freedom model, it is shown that the maximum value of EDI corresponds to a simultaneous optimization of the significant kinematic and static response quantities, independently of the input. By using the proposed procedure, the optimal design of new and existing structures equipped with VED, inserted in traditional bracing systems, are here analyzed and discussed.

Assessment of concrete strength combining direct and NDT measures via Bayesian inference     
Published by (elsevier)
Authors: renato giannini, lorena sguerri, fabrizio paolacci, silvia alessandri.  Published January 01, 2014

Assessment of the seismic vulnerability of an old RC viaduct with frame piers and study of the effec     
Published by (Luxembourg: Publications Office of the European Union, 2014)
Authors: fabrizio paolacci, pierre pegon, Francisco J. Molina, Martin Poljansek, Renato GIannini, Luigi Di Sa.  Published January 01, 2014

The RETRO project aims at studying the seismic behaviour of existing reinforced concrete bridges (RC) and the effectiveness of innovative retrofitting systems. Emphasis has been paid on old bridges generally not properly designed for seismic action. On the basis of a previous experimental campaign consisting of cyclically imposed displacements on 1:4 reduced scale models of a frame pier, belonging to a typical old RC highway viaduct, a new experimental activity has been proposed. Two specimens (scale 1:2.5), a frame pier of 2 levels (height 5.8 m) and a frame pier of 3 levels (height 10.3 m), have been built and tested using the PsD technique with sub-structuring technique, including the modelling of the entire viaduct to which they belong. Two test configurations have been considered: 1) retrofitted viaduct using Friction Pendulm Isolators, and an 2) “as-built” configuration imposing a Serviceability and Ultimate limit state conditions. For each phase of the experimental campaign model identification has been performed. The aim of the campaign was twofold: 1) increasing the knowledge on the non-linear behaviour of RC frame piers in presence of plain steel bars and detailing of the late 1950’s for which few studies have been carried out, and 2) study the effectiveness of seismic isolation systems for the seismic response mitigation.

Enhanced seismic performance of non-standard bolted flange joints for petrochemical piping systems     
Published by (elsevier)
Authors: fabrizio paolacci, Oreste S. Bursi, Md Shahin Reza, Anil Kumar.  Published June 03, 2014

This paper presents an experimental test campaign carried out on a number of seismically enhanced Bolted Flange Joints. In particular, two non-standard Bolted Flange Joints, comparatively thinner than standard ones, were designed and their performance was evaluated through several monotonic and cyclic tests. Experimental results exhibited a favourable performance of the examined joints under bending and axial loading and moderate internal pressure; a good capacity in terms of strength, ductility, energy dissipation and leakage was observed. A comparison between experimental results and Codebased design loads proved the usability of the proposed joints during and after Operating Basis Earthquake ground motions. Finally, a comparison between capacity and seismic demands of these joints adopted in a piping system of a realistic Case Study suggested their suitability for seismic applications as well as some building code deficiency with respect to response modification factors

MORTAR-BASED SYSTEMS FOR EXTERNALLY BONDED STRENGTHENING OF MASONRY     
Published by (Springer)
Authors: Gianmarco Defelice, Stefano de Santis, Leire Garmendia, Bahman Ghiassi, Pello Lar rinaga, Paulo B. L.  Published June 03, 2014

Mortar-based composite materials appear particularly promising for use as externally bonded reinforcement (EBR) systems for masonry structures. Nevertheless, their mechanical performance, which may significantly differ from that of Fibre Reinforced Polymers, is still far from being fully investigated. Furthermore, standardized and reliable testing procedures have not been defined yet. The present paper provides an insight on experimental-related issues arising from campaigns on mortar-based EBRs carried out by laboratories in Italy, Portugal and Spain. The performance of three reinforcement systems made out of steel, carbon and basalt textiles embedded in inorganic matrices has been investigated by means of uniaxial tensile coupon testing and bond tests on brick and stone substrates. The experimental results contribute to the existing knowledge regarding the structural behaviour of mortar-based EBRs against tension and shear bond stress, and to the development of reliable test procedures aiming at their homogenization/standardization

Pseudo-dynamic testing with non-linear substructuring of a reinforced concrete bridge.     
Published by (SERIES Concluding Workshop joint with NEES-US “Earthquake Engineering Research Infrastructures”, JRC)
Authors: fabrizio paolacci, Giuseppe Abbiati, Oreste S. Bursi, Enrico Cazzador.  Published 

Seismic vulnerability assessment of a high voltage disconnect switch     
Published by (Elsevier)
Authors: fabrizio paolacci, Renato Giannini, Silvia Alessandri, Gianmarco De Felice.  Published December 01, 2014

This paper deals with the seismic vulnerability of high voltage equipment typically installed in electric substations. In particular, the seismic response of a 380 kV vertical disconnect switch has been investigated based on the results of an experimental campaign carried out at Roma Tre University. According to a series of non-linear analyses, the influence of the most significant parameters on the seismic behavior of this apparatus has been analyzed and the corresponding fragility curves have been evaluated by using the Effective Fragility Analysis method. The results showed a limited vulnerability of the disconnect switch, whose most critical parts are the bottom joint of the ceramic support column and the steel column base.

ON THE EFFECTIVENESS OF TWO ISOLATION SYSTEMS FOR THE SEISMIC PROTECTION OF ELEVATED TANKS     
Published by (ASME 2014 Pressure Vessels & Piping Conference PVP2014)
Authors: fabrizio paolacci.  Published July 20, 2014

This paper deals with the effectiveness of two isolation system for the seismic protection of elevated steel storage tanks. In particular the performance of High Damping Rubber Bearings and Friction Pendulum isolators has been analyzed. As case study an emblematic example of elevated tanks collapsed during the Koaceli Earthquake in 1999 at Habas Pharmaceutics plant in Turkey has been considered. A time-history analysis conducted using lumped mass models demonstrated the high demand in terms of base shear required to the support columns and their inevitable collapse due to the insufficient shear strength. A proper design of HDRB and FPS isolator and a complete non-linear analysis of the isolated tanks proved the high effectiveness of both isolation systems in reducing the response of the case tank. Actually, a reduced level of displacements of isolators and a reduced level of convective base shear obtained with the second isolation typology, suggested the used of FPS isolators rather than HDRB.

PERFORMANCE-BASED ANALYSIS OF PETROCHEMICAL PIPING SYSTEMS LOCATED IN EARTHQUAKE-PRONE ZONES     
Published by (2 EUROPEAN CONFERENCE ON EARTHQUAKE ENGINEERING AND SEISMOLOGY - ISTANBUL)
Authors: Oreste S. Bursi, fabrizio paolacci, Md Shahin Reza.  Published August 25, 2014

plants, where they are often employed to transport dangerous goods like oil and gas. A single failure in such systems may cause serious accidents both to the environment and human lives. During past earthquakes, piping systems and their components suffered significant damages causing severe consequences, as reported in several publications. Thus, seismic assessment/evaluation of these structures has become an imperative for their proper design to safeguard them against seismic events. Nevertheless, there exists an inadequacy of proper seismic analysis and design rules for petrochemical piping systems, and designers have to follow seismic standards conceived for other structures such as buildings and nuclear plants. Moreover, the modern performance-based design approach is still not widely adopted for piping systems, where the allowable design method is the customary practice. Along these lines, this paper presents a performance-based seismic analysis of petrochemical plants through two case studies. Initially, main issues on seismic analysis and design of industrial piping systems and components are addressed followed by a discussion on the selection of proper seismic inputs. The current allowable stress and strain based seismic verification methods are presented afterward. Then, nonlinear finite element analyses of two typical petrochemical piping systems under modern design earthquake levels are presented. Finally, performance of these piping systems is commented by comparing the maximum stress and strain levels -found from the analyses- with the allowable design values that exhibited a favourable behaviour of the analysed systems under earthquake limit state levels.