Search results for "frp"

Seismic assessment and retrofit of a concrete building highly damaged by reinforcement corrosion

2020

In existing concrete structures damaged by corrosion, the limited quantity and poor distribution of reinforcements as well as a lack of seismic details are common to many cases because they are built before the advent of seismic codes. In this paper the seismic assessment and retrofit of a concrete building sited in Sicily is presented in order to show a case-study of a corroded reinforced concrete structure to be trans-formed with new structural elements for functional reasons linked to Civil Protection. After many decades of complete abandonment, the structure was strengthened with different strategies, allied to the construction of new steel-concrete composite floors: concrete and steel …

Experimental and numerical analysis of flexural behaviour of GFRP pultruded material

2014

Size effect in FRP-substrate material bonded joints

2008

Assessment of bonding defects in FRP reinforced structures via ultrasonic technique

2016

Fiber reinforced polymer (FRP) composite systems are widely used for the rehabilitation of concrete structures such as building that need to resist to seismic loads, bridges that have to carry heavier traffic loads. The technique consists in bonding the composite plate to the concrete surface element in order to increase the flexural capacity. A proper attachment of the FRP plate to the concrete surface is necessary for the efficiency of the load transfer between the reinforcement and the substrate. In this work, the quality of composite bonding is characterized through ultrasonic testing. The proposed technique is relative to a time domain analysis of the ultrasonic signals and couples the…

FRP-Substrate bonding quality investigation making use of ultrasonic waves

2016

Fiber reinforced polymer (FRP) composite systems are widely used to repair structurally deficient constructions thanks to their good immunity to corrosion, low weight and excellent mechanical properties. The quality of the FRP-substrate interface bond is a crucial parameter affecting the performance of retrofitted structures. In this framework, ultrasonic testing could be used to assess the quality of the bonding [1-2]. In the case of FRP laminates adhesively bonded to roughly inhomogeneous materials, such as concrete, high scattering attenuation occurs due to the presence of heterogeneities. The concrete behaves almost like a perfect absorber generating a considerable number of short-space…

Comportamento meccanico di una volta rinforzata con CFRP

2001

Il presente lavoro riguarda il progetto e l'esecuzione di un intervento di rinforzo di una volta a padiglione lunettata di una Villa di interesse storico-monumentale del 700. Tale volta è realizzata con conci di calcarenite inzeppati con cunei di legno e senza malta di connessione, tipologia molto diffusa in tutta l'area del mediterraneo. L’intervento è stato preceduto dallo studio del comportamento meccanico della volta in laboratorio e da prove dinamiche in sito. Particolare attenzione è stata rivolta al sistema di trasmissione dei carichi verticali allo scopo di rendere meno gravoso lo stato tensionale nella parte più alta della volta. Il sistema strutturale è stato analizzato per mezzo …

Nuove tecniche di rinforzo e adeguamento per elementi in calcestruzzo armato

2010

EXPERIMENTAL ANALYSIS OF SMALL CLAY BRICK CYLINDERS CONFINED BY BFRP GRID UNDER AXIAL COMPRESSION

2019

Many investigations have shown that fibre reinforced polymer (FRP) composites can be effectively used to induce a passive confinement action on masonry columns and improve their axial capacity and ductility. This paper presents the results of an experimental study on the compressive behaviour of clay brick masonry cylinders externally wrapped with basalt fiber reinforced polymer (BFRP) grids. The circular section shape was chosen to assess the pure confinement effect on the masonry material. Fourteen clay brick masonry cylinders, cored from two different masonry assembly types, were confined with one or two layers of BFRP grids. The two assemblies were used to investigate the effect of vert…

Sostenibilità di interventi di miglioramento sismico di strutture in c.a. non danneggiate

2012

Flexural behavior of R.C. columns externally wrapped with FRP sheets

2012

In the present paper the compressive and flexural behavior of R.C. columns externally wrapped with FRP layers is examined. The investigation refers to a short compressed R.C. member having circular transverse cross-section and reinforced with longitudinal bars and transverse hoops or spirals. A first phase of the investigation was addressed to describing the constitutive laws of constituent materials (confined concrete core, steel bars in compression and in tension, FRP in tension). The second phase of the research was addressed to deriving the compressive and flexural responses in terms of load-axial shortening curves and momentaxial force interaction domain, to be compared with experiment…