Gianvittorio Rizzano

• Phd - Full Professor
• Professor (Full) at University of Salerno

Traditional seismic design methods, suggested by current codes and conventionally applied worldwide, rely on damage to building structures to dissipate the seismic input energy. This strategy allows meeting the life safety requirements but often results in post-earthquake scenarios where building structures are severely damaged with significant dir...

Recent destructive seismic events have underlined the need for increasing research efforts devoted to the development of innovative seismic‐resilient structures able to reduce seismic‐induced direct and indirect losses. Regarding steel Moment Resisting Frames (MRFs), the inclusion of Friction Devices (FDs) in Beam‐to‐Column Joints (BCJs) has emerge...

This paper presents a dataset of cyclic tests and FE simulations of T-joints with Circular-Hollow-Section (CHS) chords and passing-through plates. These specimens were designed to be representative of components of beam-to-column joints between CHS columns and passing-through IPE beams, subjected to the cyclic load protocol proposed by AISC 341. Sp...

Recent studies highlighted the importance of an accurate assessment of the remaining life of historical steel riveted bridges to plan and design their maintenance. Such structures are usually prone to fatigue damage due to the high number of cumulated cyclic stresses over their service life. Currently, limited guidelines are available for evaluatin...

Bridges are vital components of any existing infrastructure, enabling essential links for transportation and commerce. In Italy, a nation renowned for its historical bridges, the importance of proper risk classification, safety assessment and monitoring of existing structures is of paramount importance. Risk classification involves categorizing bri...

In recent decades, low-yielding seismic devices based on the use of friction dampers have emerged as an excellent solution for the development of building structures with improved reparability and resilience. Achieving an optimal design for such low-yielding seismic devices requires precise control of bolt preloading levels and predictability of th...

Metal foams are newly developed engineered materials with attractive mechanical properties such as lightness, high resistance-to-weight ratio, and insulation capabilities. Lately, applications of these technologies have demonstrated the possibility of obtaining high-performance sandwich panels with steel skins and metal foam core, with potential ap...

This manuscript explores the stiffness and strength of Square Hollow Section (SHS) tubes subjected to localised transverse actions applied to the open side of a rectangular hole created using 3D laser cutting technology (3D-LCT). Understanding the behaviour of this specific detail is crucial as it is a key component in the connections between SHS c...

The usage of non-destructive techniques for structure's state assessment is highly desirable because they offer the possibility to monitor continuously and in a non-invasive manner the sign of failures of any structure. Among the several techniques proposed over the years, Acoustic Emission (AE) seems very promising. Such a technique, which applies...

Steel structures can be designed according to different framing methods depending on the location of Moment‐Resisting‐Frames (MRFs). In Europe and the United States, one‐way MRFs are widely exploited due to their ability to clearly identify the seismic and gravity frames and limit the use of expensive joints only in MRFs. Furthermore, this is the m...

This paper investigates the cyclic behaviour of a novel typology of steel beam‐to‐column connection made by welding circular hollow section (CHS) columns and through I‐beams. In fact, due to the novelty of this configuration and the lack of design equations in the current codes, the application of this innovative solution is limited in common pract...

The use of Square‐Hollow‐Section (SHS) members as columns of moment‐resisting frames is a very interesting solution thanks to several benefits they can provide. However, especially in Europe and the USA, the use of SHS columns is limited by the complexity related to the realisation of beam‐to‐column connections. Nevertheless, the recent use in civi...

In the last few decades, increasing research efforts have been devoted to the definition of innovative seismic resilient design strategies with the aim of reducing direct and indirect losses. Among others, the use of Friction Devices (FDs) for Beam‐to‐Column joints (BCJs) has emerged as an effective solution to ensure the damage‐free behaviour of s...

Old‐steel riveted bridges are part of the heritage asset in many countries. Assessing the remaining life and fatigue strength of their structural riveted details is crucial in managing these structures. According to JRC‐ECCS document Assessment of Existing Steel Structures: Recommendations for Estimation of Remaining Fatigue Life , fatigue class 71...

Bolts in tapped holes (BTH) use threads on the bolt hole wall as an anchorage instead of nuts used in standard bolt assemblies. Requirements for BTH application are given in the draft version of new Eurocode prEN 1993‐1‐8, including the definition of minimum thread engagement lengths. BTH connected T‐stubs under tension were investigated in analyti...

The capacity of steel Moment Resisting Frames (MRFs) to survive to extreme load is strictly linked to the moment‐rotation capacity of the beam‐to‐column connections. In those conditions, i.e., in extreme loading conditions, catenary actions develop in the connected beam leading in large joint rotations. The current European code, the Eurocode 3 Par...

Metal foam is a relatively new and potentially revolutionary material due to its properties such as the low weight‐to‐stiffness ratio, high damping and energy dissipation capacity. Even if this material is widely used in mechanical, aerospace and automotive industries, it is still not frequently used in civil engineering applications. The large ene...

The component method is a powerful tool for designing and modelling steel beam-to-column connections. Its widespread use is ensured by several formulations currently included in Eurocode 3 part 1.8 for welded and bolted joints. However, the recent use of 3D Laser Cutting Technology (3D-LCT) in the construction market has enlarged the range of solut...

Background Recent computing improvements have allowed a considerable use of numerical models to predict phenomena concerning various topics. In particular, considering the field of civil engineering, the possibility of having greater computational capabilities has guaranteed to explore both the global and local behaviour of buildings with greater a...

3D laser cutting technology is a new automatised industrial process allowing the development of a range of novel applications in civil engineering. Its main advantage derives from the possibility to manufacture easily tridimensional cutting shapes with high precision (accuracy of about 10μm), minimising the hole size, optimising the welding quantit...

In recent years there have been significant advancements in the definitions of innovative seismic-resilient structural systems, chasing the urgent need to reduce repair costs and downtime in the aftermath of severe earthquake events. In this regard, self-centring Column Bases (CBs) represent a promising solution to improve the seismic performance o...

To provide a tool able to deliver an accurate prediction of the response of bolted T-stubs, a novel mechanical model based on a step-by-step integration algorithm is presented. It explicitly considers some complexities occurring in the large displacement range, with detailed non-linear modelling of the sources of strength and deformability. As show...

This paper is devoted to a brief presentation of the main results obtained within the FREEDAM research project. The project has been completed and, recently, also the dissemination of the results has reached the finish line. The project was devoted to the development of low-damage beam-to-column connections based on the use of friction dampers conc...

The application of tubular columns in steel structures offers many advantages. However, this potential has not been fully utilized due to a lack of access for the installation of standard bolts in end-plate beam-to-column joints. Blind bolts are an alternative way of connecting the beam end-plate to hollow section column, for they can be installed...

The aim of the work is the evaluation of the ultimate behaviour of aluminium channel sections subjected to local buckling under uniform compression. In particular, two different approaches are presented to predict the inelastic response of aluminium members: the Deformation Theory of Plasticity (DTP) and the Effective Thickness Method (ETM). The fi...

Many recent research studies have focused on the development of innovative seismic-resilient structural systems to reduce repair costs and downtime in the aftermath of severe earthquake events. In this regard, dealing with steel Moment Resisting Frames (MRFs), recent experimental and numerical studies have demonstrated the benefits deriving from th...

Nominated for Eurosteel 2021 Best Paper Award In recent decades, innovative seismic‐resilient structural systems have been proposed to reduce the direct and indirect losses related to seismic events. Among others, steel moment‐resisting frames (MRFs) equipped with damage‐free self‐centring column bases (SC‐CBs) represent a promising solution. Altho...

Nominated for Eurosteel 2021 Best Paper Award The introduction to the market of metal foams represents a significant opportunity to increase the use of metal in the construction market. In fact, the development of new products made of metal foams and steel could improve the performance of conventional buildings in terms of stiffness and resistance....

The recent earthquakes have underlined the need for more advanced design philosophies able to avoid or reduce direct and indirect costs related to the occurrence of destructive seismic events. According to the traditional seismic design approach, under rare and very rare seismic events, the onset of damage to structural components is usually accept...

The use of circular hollow section (CHS) members as columns of moment-resisting frames is limited by the complexity related to the realization of beam-to-column connections. Nevertheless, the recent use in the field of civil engineering of the Laser Cutting Technology (LCT) has offered the opportunity to manufacture welded connections by properly c...

In the last two decades, increasing efforts have been devoted to the definition of innovative seismic design philosophies, with the aim of reducing seismic induced direct and indirect losses. Among others, beam-to-column connections equipped with friction devices have emerged as an effective solution to dissipate the seismic input energy while also...

The brittle fracture experienced by the welds of full-strength joints belonging to steel moment-resisting-frames (MRFs) during the earthquakes of Northridge (1994) and Kobe (1995) represented a turning point in the seismic design of steel structures. In fact, after these events, different strategies have been proposed to solve this drawback. The us...

Earthquake resilient steel frames, such as Self-Centring Moment Resisting Frames (SC-MRFs) or Concentrically Braced Frames (SC-CBFs), have been widely studied during the past few years while little attention has been paid to the development of self-centring solutions based on Eccentrically Braced Frames (EBFs). The present paper investigates a poss...

In the last two decades many researchers focused on the development of innovative building structures with the aim of achieving seismic resilience. Among others, steel Moment Resisting Frames (MRFs) equipped with friction devices in beam-to-column joints have emerged as an effective solution able to dissipate the seismic input energy while also ens...

Low‐damage and self‐centring column base connections have been proposed in the last two decades as innovative solutions able to provide the seismic resilience in Moment Resisting Frames (MRFs). Although many works have demonstrated the benefits deriving from the adoption of these systems, only a few research studies investigated the significant par...

The introduction in the market of metal foams represents a significant opportunity to increase the use of metal in the construction market. In fact, the development of new products made of metal foams and steel could allow improving the performances of conventional buildings in terms of stiffness and resistance. The first structural applications of...

In the last two decades many researchers focused on the development of innovative building structures with the aim of achieving seismic resilience. Among others, steel Moment Resisting Frames (MRFs) equipped with friction devices in beam-to-column joints have emerged as an effective solution able to dissipate the seismic input energy while also ens...

After the earthquakes of Kobe (1995) and Northridge (1994) many research efforts have focused the attention on the seismic behaviour of partial strength beam-to-column joints because, in these seismic events, brittle fractures of welds of full-strength joints belonging to MRFs have been observed. One of the most popular solutions developed in the a...

This paper investigates the mechanical behaviour of a novel typology of steel beam-to-column connection made by welding circular hollow section (CHS) columns with through-all double-tee beams. Such connection represents an alternative to the classical configuration with the I-beam simply welded to the external surface of the hollow profile for whic...

The recent earthquakes have underlined the need for more advanced design philosophies able to avoid or reduce direct and indirect costs deriving from the occurrence of destructive seismic events. In fact, the traditional seismic design approach is based on performance levels implying the onset of damage which can be, in many cases, difficult to rep...

Low-damage and self-centring column base connections have been proposed in the last two decades as innovative solutions able to provide the seismic resilience in Moment Resisting Frames (MRFs). Although many works have demonstrated the benefits deriving from the adoption of these systems, only a few research studies investigated the significant par...

In steel structures, owing to technological aspects, frequently bolting access is difficult. To overcome these issues, technological research has proposed in the last decades several blind bolt systems that allow the installation of a bolt working only on one side of the connection. The simplest type of blind bolt is the thread-fixed one side bolt...

Many recent research studies have focused on developing innovative seismic-resilient structural systems to reduce repair costs and downtime in the aftermath of an earthquake. In this regard, dealing with steel Moment Resisting Frames (MRFs), recent research works have demonstrated the benefit deriving from the adoption of both low-damage and self-c...

Metal foams are engineered materials with attractive mechanical properties such as lightness, energy dissi-pation capacity, high resistance and stiffness. To date, the applications of these materials are mainly limited to aeronautic and mechanical engineering. However, their features can provide significant advantages also for the development of ne...

This paper investigates the development of second (2nd) order effects, arising from geometric and material non-linearities of T-stubs bolted to a rigid support, through a combination of experimental, numerical and analytical approaches. Experimental data is presented for a broad range of T-stub geometries, designed to ensure that significant 2nd or...

Free from damage beam-to-column joints: Testing and design of DST connections with friction pads

This work aims to enhance the energy-dissipation capacity of classical rectangular T-stubs by proposing an hourglass shape for the T-stub flange according to the approach usually adopted for added damping and stiffness (ADAS) devices. A new type of axial damper is developed. First, a mechanical model of the device is set up and a finite-element mod...

In this paper, the friction coefficient and the cyclic response of different interfaces for friction devices are investigated by means of experimental tests under displacement control. In particular, six interfaces have been tested: steel–steel, brass–steel, sprayed aluminum–steel and three different rubber based friction materials adopted, respect...

The behavior of steel structures is significantly affected by the connections between the steel members. For this reason, special attention to the prediction of the joint rotational behavior is devoted by Eurocode 3 which provides the well-known component method. In EC3, starting from the results of several researches, the formulations for the char...

The work is aimed at the prediction of the cyclic response of bolted beam-to-column joints starting from the knowledge of their geometrical and mechanical properties. To this scope a mechanical model is developed within the framework of the component approach already codified by Eurocode 3 for monotonic loadings.Accuracy of the developed mechanical...

This article aims to propose an innovative type of angle to be used in substitution of the hold-down in cross-laminated timber (CLT) panel buildings. The new connection, called XL-stub, applies a concept similar to the classical ADAS (added stiffness and damping) device. In order to characterize the force-displacement response under cyclic loads of...

This work deals with the prediction of the bearing resistance of elementary shear connections constituted by gusset plates and square hollow sections fastened with long bolts. The research is motivated by the lack of specific rules in international codes for this particular configuration. In fact, while in lap shear connections, single or double-si...

Beam-to-column joints equipped with friction dampers are promising solutions to improve the performance of steel moment resisting frames due to the possibility to guarantee large dissipation capacity limiting the structural damage under severe seismic conditions. In this paper, the experimental tests and the numerical simulations of two types of jo...

In this paper, the results of an experimental analysis regarding beam-to-column joints equipped with friction dampers is presented. Even though the overall concept is not new, the connection structural detail and the friction pad material are different from previous proposals. In particular, the beam is connected to the column with a classical fixe...

The sliding hinge joint (SHJ) is a supplemental energy dissipation system for column bases or beam-to-column connections of steel Moment Resisting Frames (MRFs). It is based on the application of symmetric/asymmetric friction dampers to develop a dissipative mechanism alternative to the column/beam yielding. This typology was initially proposed in...

Many recent research studies focused on the development of innovative seismic resilient structures by chasing the objectives of minimising both seismic damage and repair time, hence allowing the definition of structures able to go back to the undamaged, fully functional condition, in a short time. In this context, the present study investigates an...

In the last few decades, increasing efforts have been devoted to the development of beam-to-column connections able to accommodate the local ductility demand dissipating, contemporaneously, the seismic input energy. Among the typologies proposed, the so-called RBS (Reduced Beam Section) has gained wide acceptance in the construction market, leading...

A novel solution offered by the 3D Laser Cutting Technology, in the field of civil engineering, consists in the possibility of coupling hollow section columns with through I-beams. Such a kind of joint is alternative to the configuration with the I-beam simply welded to the external surface of the hollow profile for which Eurocode 3 part 1.8 provid...

This paper deals with the study of the mechanical behaviour of a novel typology of steel beam-to-column connection made by welding circular hollow section (CHS) columns with through-all I-beams. Such connection represents an alternative to the classical configuration with the I-beam simply welded to the external surface of the hollow profile for wh...

In the case of steel Moment Resisting Frames (MRFs), the adoption of beam-to-column joints equipped with friction dampers represents an efficient alternative to traditional joint typologies. In fact, the introduction of devices able to dissipate the seismic input energy providing only low or negligible damage leads to significant benefits in terms...

Background The performances of composite steel-concrete slabs are strongly influenced by the connection between the concrete and the steel decking, which is essentially assured by bonding, interlocking, and adhesion. The connection can be continuous or localized by means of connectors. In order to increase the bonding between steel and concrete ele...

Background Forthe reliable prediction of the non-linear response of structures, severe seismic events have proven to be a challenging task. Although much non-linear analysis software exists, the accuracy of the results depends on the assumptions made in the characterization of the members. Typically, the analytical models are calibrated using exper...

Double-tee profiles are the most popular members in Europe and the USA for steel structures. However, more efficient cross-sections, such as circular hollow sections (CHSs), could be adopted, since they can provide higher aesthetic, economic and mechanical benefits, with the only drawback of more complex connections such as in the case of I-beams w...

Among the accidental loading scenarios, the vehicle collision in the ground column of a building is surely one of the most common. When a building is subjected to such an action, the beam-to-column connections are responsible for the transfer of the actions through an alternative path, thus, playing an important role in the robustness of the buildi...

The paramount role of beam-to-column joints on the seismic response of MRFs is universally recognised and many studies have been devoted to the improvement of their ductility and energy dissipation capacity, mostly after the seismic events of Northridge and Kobe. Nevertheless, while much experimental work has been already carried out on the seismic...

The studies related to the behaviour of steel connections subjected to extreme conditions originated from impact loads have increased in the last few years. However, there is still no consensus on how exactly the whole connection and its individual components behave when subjected to high strain rates, which is translated by the lack of codified de...

Hybrid Steel Trussed Composite Beams represent a technical solution in use in numerous countries since many years. They are able to join the advantages of prefabrication with those of cast in place structures: they are easy to manufacture, fast to realize, monolithic and with no need of formwork. The behavior of these beams has been recently topic...

Dealing with steel Moment Resisting Frames (MRFs) the current European seismic design rules suggest, in case of severe earthquakes, to enforce the formation of plastic zones in members or joints. When joints are the main source of energy dissipation, a thorough knowledge of their inelastic behaviour is needed. This is the reason why, in past years,...

In this paper, an experimental campaign devoted to the response of a friction damper subjected to uniaxial quasi-static and impact tension loads is presented. The friction damper analysed in this paper constitutes the dissipative part of a new type of dissipative beam-to-column connection, called Sliding Hinge Joint. A total of 8 quasi-static tests...

In the last two decades many researchers focused on the development of innovative building structures with the aim of achieving seismic resilience. Among others, steel Moment Resisting Frames (MRFs) equipped with friction devices in beam-to-column joints have emerged as an effective solution able to dissipate the seismic input energy while also ens...

Abnormal loading, such as impact, can induce failure in the elements directly exposed to the hazard or even cause the progressive collapse of the building. Therefore, the structural robustness of buildings to such loading conditions should be checked. In this regard, connections play a fundamental role and, consequently, the knowledge of their resi...

The aim of this paper is to provide a contribution to the knowledge of steel connections subjected to rapidly applied dynamic loads up to failure. In particular, the attention is focused on the behaviour of the dissipative component of a friction joint, i.e. the friction damper. An analytical model based on the component method of the Eurocode 3 pa...