Stefano BARONE

Liquified Natural Gas tanks (LNG) are lifeline facilities and strategically very important, since they have vital use in industries and nuclear power plants. These special structures are often located in seismic prone areas; in these cases, seismic isolation is worldwide extensively used to reduce the dynamic response of the tanks, thus avoiding typical forms of failure such as diamond-shaped buckling, elephant-foot buckling and roof damage due to sloshing. Moreover, base isolation, decoupling… Visualizza altro

Liquified Natural Gas tanks (LNG) are lifeline facilities and strategically very important, since they have vital use in industries and nuclear power plants. These special structures are often located in seismic prone areas; in these cases, seismic isolation is worldwide extensively used to reduce the dynamic response of the tanks, thus avoiding typical forms of failure such as diamond-shaped buckling, elephant-foot buckling and roof damage due to sloshing. Moreover, base isolation, decoupling the motion of the tank from that of the ground, allows to optimize and therefore to reduce costs, not only of the superstructure but also of the substructure, such as foundation piles. This paper describes the seismic isolation of 2 x 10130 m 3 working capacity LNG full containment storage tanks located at Corsini port, Ravenna, Italy, area characterized by medium seismicity. Each LNG tank consists of an inner steel tank, which contains the LNG, and an outer prestressed concrete tank that encases and protects the inner tank. 182 high-friction curved surface sliders (91/tank) were designed, manufactured and tested by Freyssinet Italy, to ensure high lateral flexibility and energy dissipation capacity to the isolation system. This works represents the first important example of seismic isolation of LNG tanks in Italy through friction-based devices. Meno dettagli

ABSTRACT
This paper presents a summary of the experimental dynamic response of curved surface sliders as resulting from more than 1000 dynamic tests on about 60 different types of devices performed at the laboratory of the EUCENTRE Foundation. Two different kinds of low-friction sliding materials have been employed in the devices, derived from polyamide (PA) or polyethylene (PE) materials. The rate of change of the dynamic friction coefficient as function of sliding velocity and contact… Visualizza altro

ABSTRACT
This paper presents a summary of the experimental dynamic response of curved surface sliders as resulting from more than 1000 dynamic tests on about 60 different types of devices performed at the laboratory of the EUCENTRE Foundation. Two different kinds of low-friction sliding materials have been employed in the devices, derived from polyamide (PA) or polyethylene (PE) materials. The rate of change of the dynamic friction coefficient as function of sliding velocity and contact pressure is assessed and the transition phase between dynamic and static friction, with the consequent possible evidence of static/stick-slip phenomena, has been carefully considered.

Keywords: Base Isolation, Friction-Based Devices, Polyamide (PA), Polyethylene (PE), Experimental Dynamic Response, Friction Coefficient, Contact Pressure, Sliding Velocity

DOI: 10.1080/13632469.2017.1387201
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ABSTRACT
Aim of this work is to characterize the frictional properties of different sliding materials employed in isolation devices, such as Curved Surface Sliders (CSS). This study is based on the results of a large experimental campaign of tests conducted on more than 70 different types of CSS, performed over several years at the experimental facility of the EUCENTRE Foundation. The friction sliding materials employed in the devices are derived from polyamide (PA), polyethylene (PE) or… Visualizza altro

ABSTRACT
Aim of this work is to characterize the frictional properties of different sliding materials employed in isolation devices, such as Curved Surface Sliders (CSS). This study is based on the results of a large experimental campaign of tests conducted on more than 70 different types of CSS, performed over several years at the experimental facility of the EUCENTRE Foundation. The friction sliding materials employed in the devices are derived from polyamide (PA), polyethylene (PE) or polytetrafluoroethylene (PTFE). The variation of the friction coefficient as function of sliding velocity and contact pressure has been carefully considered; the possible evidence of static/stick-slip phenomena at reversal phases is also assessed. Finally, experimental equations are derived to define friction - velocity - pressure surfaces for each sliding material considered.

Keywords: Experimental Response of Curved Surface Sliders (CSS), Friction Sliding Materials, Polyamide (PA), Polyethylene (PE), Polytetrafluoroethylene (PTFE).

DOI 10.7414/7aese.T1.28
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ABSTRACT
High-seismicity regions require advanced earthquake protection systems. Turkey is one of the most seismically active regions in the world; its capital city, Istanbul, has an ever-increasing demand of public transportation between different parts of the city. The Alibeyköy and Kagithane viaducts are integral part of the new Istanbul metro line and represent an extraordinary worldwide example of base isolation and energy dissipation through the combination of different types of… Visualizza altro

ABSTRACT
High-seismicity regions require advanced earthquake protection systems. Turkey is one of the most seismically active regions in the world; its capital city, Istanbul, has an ever-increasing demand of public transportation between different parts of the city. The Alibeyköy and Kagithane viaducts are integral part of the new Istanbul metro line and represent an extraordinary worldwide example of base isolation and energy dissipation through the combination of different types of anti-seismic devices.
The seismic protection is obtained through spherical bearings able to support vertical loads up to 60.000 kN with maximum displacement capacity in longitudinal and transversal directions equal to ±350 mm. The bearings are equipped with CE marked anti-seismic devices with high hysteresis capacity and high strength sliding material with frictional properties to improve the overall dissipation capacity. The hysteretic dampers are made by “E” and “C” shaped steel elements. Some of these bearings are equipped with lock-up devices to allow service movements and to activate the hysteretic dampers during the seismic event. The paper describes in detail the need of multi-functional solution covering the full range of products available for seismic protection and all the tests performed to qualify the behavior of the devices.

Keywords: Base Isolation; Energy Dissipation; Viaducts; Anti-seismic Devices
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ABSTRACT
Large cities facing post-seismic event trauma frequently make the choice of base isolation technology for the retrofitting or reconstruction of their strategic facilities to guarantee the continuity of the services critical to their population. Consequently, most hospital and other emergency buildings are base isolated in earthquake prone cities. On the contrary, the technology is very seldom used for residential buildings. In cities where a large part of the private housing… Visualizza altro

ABSTRACT
Large cities facing post-seismic event trauma frequently make the choice of base isolation technology for the retrofitting or reconstruction of their strategic facilities to guarantee the continuity of the services critical to their population. Consequently, most hospital and other emergency buildings are base isolated in earthquake prone cities. On the contrary, the technology is very seldom used for residential buildings. In cities where a large part of the private housing building stock is made of 8 to 12-storey high RC frame buildings, two reasons are usually put forward to discard retrofitting by base isolation: the supposed high cost of the isolation system and its low efficiency due to the flexibility of the RC frame. Two recent case studies demonstrate the relevance of base isolation for the retrofitting of typical RC frame housing building. The design of the retrofitting of an 11-storey RC frame structure in Mexico City will first be presented. The second case study will detail the Moda Building in Istanbul, a 10-storey RC structure for which seismic retrofitting has recently been completed by Freyssinet using base isolation. The base isolation retrofitting of these two flexible buildings will be detailed in this paper, demonstrating the efficiency of such retrofitting solution for residential building, both in terms of cost and dynamic behaviour.
Keywords: Structural Engineering; Seismic Isolation; Residential Buildings; RC Frame Structures; Practice Case Studies
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ABSTRACT
The dynamic response of seismically-isolated buildings and infrastructures is mainly controlled by the anti-seismic devices provided in structures. For this reason, these special devices must be accurately engineered and manufactured to be compliant to the design characteristics provided by the designer. In this context, the European Standard EN 15129:2009 is one of the most advanced worldwide code which specifies functional requirements, general design rules of the devices for… Visualizza altro

ABSTRACT
The dynamic response of seismically-isolated buildings and infrastructures is mainly controlled by the anti-seismic devices provided in structures. For this reason, these special devices must be accurately engineered and manufactured to be compliant to the design characteristics provided by the designer. In this context, the European Standard EN 15129:2009 is one of the most advanced worldwide code which specifies functional requirements, general design rules of the devices for seismic design situations, material characteristics, manufacturing and testing requirements, as well as assessment and verification of constancy of performance, installation and maintenance requirements. Moreover, the EN15129:2009 is integrated with other harmonized standards for CE marking to ensure anti-seismic devices conformity and access to the entire European market. For this reason, this standard is increasingly adopted even in non-European countries, with the aim of imposing and ensuring high levels of quality and performance of the devices.
This paper illustrates the application of European Standard to an extraordinary project outside Europe: the Jakarta-Cikampek elevated toll.

Keywords: Base Isolation; Anti-seismic Devices; Lead Rubber Bearing (LRB); EN 15129:2009; CE marking
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ABSTRACT
Anthropic activities such as hydrocarbon production, gas storage, subterranean seizure of CO2, can produce seismic events of two different nature: induced earthquakes that occur because of the above-mentioned activities (not linked to the movements of faults) and triggering earthquakes, that is, linked to fault ruptures. In the last case, the anthropic activity may have disturbed a naturally almost critical situation (e.g. it changed the rupture time), thus the nature of the ground… Visualizza altro

ABSTRACT
Anthropic activities such as hydrocarbon production, gas storage, subterranean seizure of CO2, can produce seismic events of two different nature: induced earthquakes that occur because of the above-mentioned activities (not linked to the movements of faults) and triggering earthquakes, that is, linked to fault ruptures. In the last case, the anthropic activity may have disturbed a naturally almost critical situation (e.g. it changed the rupture time), thus the nature of the ground shaking is the same of natural seismicity. On the contrary, induced earthquakes produce shaking scenarios significantly different from the ones of natural events and are characterized by low magnitude and focal depth and few significant cycles. Therefore, given the low severity, it is expected damage to non-structural elements only. Focus of this work is the calibration of parameters for the determination, through the mechanical methodology SP-BELA, of fragility curves for reinforced concrete (RC) buildings with variable number of floors, subjected to induced seismicity. In particular it is defined a fragility curve representative of a limit state that activates minor damages to infill panels. The calibration is obtained through non linear time-history analysis performed on a 4-storey RC building selected to be representative of the Italian as built, designed for gravity loads only, infilled with unreinforced masonry panels. For Italian sites, there are currently no signals of relevant intensity; therefore, to perform time-history analysis, artificial accelerograms were generated according to specific induced seismicity spectral shapes.

Keywords: Induced seismicity; RC buildings; Fragility curves; Non-structural elements Meno dettagli

ABSTRACT
The growing of the goods traffic by shipping in Northern Italy stressed the need of having wide logistic platforms for the management of the goods, organizing their stock, ships docking and link with infrastructures. The new logistic platform based in Trieste will improve the movement of goods from central Europe and Turkey with an estimated yearly turnover of 15 million euros. It is is made by a 50 cm thick post-tensioned concrete slab. Base isolation was chosen to fully protect… Visualizza altro

ABSTRACT
The growing of the goods traffic by shipping in Northern Italy stressed the need of having wide logistic platforms for the management of the goods, organizing their stock, ships docking and link with infrastructures. The new logistic platform based in Trieste will improve the movement of goods from central Europe and Turkey with an estimated yearly turnover of 15 million euros. It is is made by a 50 cm thick post-tensioned concrete slab. Base isolation was chosen to fully protect the structure from strong earthquakes. For this purpose, 850 CE marked curved surface sliders were supplied by Freyssinet. These anti-seismic devices allow large relative displacements through sliding on special frictional surfaces. Moreover, the double surface configuration allowed to significantly reduce the overall dimensions of the device while maintaining high displacement capacity.
This paper describes the isolation system from the seismic analysis of the overall structure to the tests performed on the devices as well as the post-tensioning system and the expansion joints. This project is a great example of application of post-tensioning and seismic isolation techniques, a complete solution that allows to drastically reduce shear demand at the foundation level, a fundamental target for marine structures that require deep foundations.

Keywords: Harbor Logistic Platform; Post-Tensioning; Base Isolation; Curved Surface Sliders; Full-Scale Tests

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