1,721,046 research outputs found
Force-based seismic design of mixed CLT/Light-Frame buildings
No full textThis paper presents the results of a numerical study aimed to investigate the seismic behaviour of mixed multistorey
wood buildings made of CLT and Light-Frame shear walls acting at the same level. Eurocode 8 provides
little information on the seismic design of buildings with different lateral load resisting systems working at the
same level. A suggestion is given to perform non-linear static or non-linear dynamic analysis to design the
structure. The application of linear analysis methods using the force-based procedure is not possible since the
value of the behaviour factor q of the mixed system is unknown. The aim of this investigation is to propose a
simple analytical formulation to estimate the value of the q-factor of the mixed system, so as to enable the use of
the force-based philosophy of Eurocode 8 for the seismic design of mixed CLT/Light-Frame buildings. This was
achieved by analysing the results of non-linear dynamic (time-history) analyses performed on a four-storey casestudy
building with different combinations of CLT and Light-Frame shear walls. Finally, the validity of the
proposed formulation is checked by means of non-linear dynamic (time-history) analyses performed on the same
four storey case-study building in one of the hybrid combinations of CLT and Light-Frame shear walls
"Wenn die Dichtkunst für Vernunft redet". Herder von Iduna zu Adrastea
No full textDer Artikel konzentriert sich auf die Metamorphose des Mythos in Herders Werk, von "Adrastea" bis "Iduna oder der Apfel der Verjüngung"
An upgrade of existing practice-oriented FE design models for the seismic analysis of CLT buildings
No full textPractice-oriented finite element (FE) modelling strategies represent a fundamental tool for the seismic analysis
and design of Cross Laminated Timber (CLT) structures. Although substantial research has been undertaken
concerning the seismic behaviour of CLT buildings, practice-oriented FE modelling strategies are still at an early
stage. This paper presents an upgrade of an existing practice-oriented FE design model for the seismic design of
CLT structures. The upgrade is supported through the same modelling strategy presented by Christovasilis et al.
(2020) adding some features of analytical equations models presented by Casagrande et al. (2016).
2D elements are used both for the modelling of CLT panels and for mechanical connections, which are represented
by a horizontal strip with a height smaller than 7% of the height of the panel. Analytical equations for
determining the elastic modulus of elasticity and the shear modulus of the horizontal strip are reported accounting
for both rocking and sliding behaviour for single- and multi-panel CLT shearwalls, including the effect
of the vertical loads by using a secant stiffness. The validation of the proposal is carried out in terms of the
shearwall lateral stiffness through the results of experimental tests on full-scale shearwalls published by other
authors and through a validation/comparison between a detailed non-linear model and the Christovasilis et al.
(2020) strategy on two multi-storey seismic-resistant lateral systems configurations with different amount of
vertical loads. Finally, a proposal for the initial layout of connections to reduce the iterative seismic design and
analysis process for CLT buildings is presented through a case study
Westward range expansion of the Lessepsian migrant Fistularia commersonii (Fistulariidae) in the Mediterranean Sea, with notes on its parasites
No full textOne adult female bluespotted cornetfish Fistularia commersonii was captured near the coast of Arbatax (Sardinia, Italy) in late October 2005. Macroscopic and microscopic analysis of the gonad revealed a postspawning ovary. Several body parts of the damselfish Chromis chromis were found in its stomach contents. Different developmental stages of 58 metazoan parasites belonging to Arthropoda, Nematoda and Platyhelminthes were detected in its mouth and digestive tract. The lepocreadiid Allolepidapedon fistulariae was reported for the first time from the Mediterranean and, with the exception of this species, all the parasites found were reported for the first time in this host. This new record of F. commersonii may confirm the rapid range expansion of this Lessepsian migrant in the western Mediterranean Sea, as well as the presence of its endoparasite A. fistulariae.One adult female bluespotted cornetfish Fistularia commersonii was captured near the coast of
Arbatax (Sardinia, Italy) in late October 2005. Macroscopic and microscopic analysis of the
gonad revealed a postspawning ovary. Several body parts of the damselfish Chromis chromis
were found in its stomach contents. Different developmental stages of 58 metazoan parasites
belonging to Arthropoda, Nematoda and Platyhelminthes were detected in its mouth and
digestive tract. The lepocreadiid Allolepidapedon fistulariae was reported for the first time from
the Mediterranean and, with the exception of this species, all the parasites found were reported
for the first time in this host. This new record of F. commersonii may confirm the rapid range
expansion of this Lessepsian migrant in the western Mediterranean Sea, as well as the presence
of its endoparasite A. fistulariae
North-easternmost record of Halosaurus ovenii (Actinopterygii: Notacanthiformes: Halosauridae) in the Mediterranean Sea, with notes on its biology
No full textA single adult female specimen of Halosaurus ovenii Johnson, 1864 was captured by trammel nets at a depth of about 200 m off the coast of Arbatax (Sardinia, Italy) in early April 2007. Macroscopic and microscopic analysis of the gonad showed a postspawning ovary. This is the fourth documented capture of this fish in the Mediterranean Sea, representing the north-easternmost record for this species in this geographic area. Furthermore, the present specimen was fished at the shallowest depth ever recorded before
“Seismic design of multi-storey CLT buildings according to Eurocode 8.”
No full textLe strutture in Cross Laminated Timber (CLT) – o Legno Lamellare Incrociato – sono sempre più utilizzate in tutto il mondo e principalmente in Europa, dove il sistema ha avuto origine. Tuttavia, nonostante questa diffusione abbia portato alla realizzazione di un gran numero di edifici multipiano in tutta Europa, mancano ancora all’interno degli Eurocodici indicazioni e regole di progettazione per questa tipologia di edifici, soprattutto per quanto concerne la progettazione antisismica. Cionondimeno l’Eurocodice 8 richiede in molti casi, a causa del non soddisfacimento dei criteri di regolarità per la maggior parte degli edifici, l’uso dell’analisi modale con spettro di risposta, ossia l’analisi dinamica lineare. Questo metodo richiede la stima corretta della rigidezza laterale
dell’edificio al fine di calcolare esattamente le forze sismiche di progetto, che possono essere significativamente sottovalutate o sovrastimate in funzione delle dimensioni dell’edificio e della forma dello spettro di progetto. A questo scopo è necessario modellare ogni singola connessione basandosi su risultati sperimentali disponibili, che non sono però facilmente accessibili per un progettista. In questo articolo viene proposto un metodo di progettazione per la modellazione dinamica lineare di strutture in CLT utilizzando SAP 2000. Le formule proposte sono basate sui riferimenti normativi e bibliografici disponibili, e vengono utilizzate per la progettazione di un caso studio di un edificio di 3 piani. Vengono inoltre presentate ulteriori indicazioni per la progettazione sismica di edifici in CLT che non sono attualmente incluse nell’Eurocodice 8. Infine, il modello di progettazione proposto è anche confrontato con i risultati di prove sismiche su tavola vibrante condotte su un edificio in CLT di tre piani nel 2006 in Giappone dal CNR-IVALSA.Cross Laminated Timber (CLT) structures are nowadays increasingly used worldwide and mostly in Europe where the system originated. However, in spite of this diffusion which led to the construction of a great number of multi-storey buildings all over Europe, still Eurocodes are almost completely missing provisions for CLT designers, especially regarding the seismic design. Nevertheless, Eurocode 8 requires in most cases, due to the regularity criteria being not fulfilled for most of the buildings, the use of the modal response spectrum analysis method, i.e. the linear dynamic analysis. This method requires the correct estimation of the lateral stiffness of the building in order to accurately calculate the design seismic forces in the building, which may be significantly underestimated or overestimated depending on the size of the building and the shape of the design spectrum. This can be done by modelling each connection with different methods that are often based on available test results, which are not easily accessible by a practicing engineer. This paper provides a design approach for dynamic linear modelling of CLT structures using SAP 2000. Equations are proposed based on available design codes and literature references, and used to design a 3-storey case study building. Further provisions for the seismic design of CLT buildings which are not included in Eurocode 8 are also given. Finally, the proposed design model is also compared with the results of the shaking table tests conducted in 2006 in Japan by CNR-IVALSA on a three-storey CLT building
“Seismic design of multi-storey CLT buildings according to Eurocode 8.”
No full textLe strutture in Cross Laminated Timber (CLT) – o Legno Lamellare Incrociato – sono sempre più utilizzate in tutto il mondo e principalmente in Europa, dove il sistema ha avuto origine. Tuttavia, nonostante questa diffusione abbia portato alla realizzazione di un gran numero di edifici multipiano in tutta Europa, mancano ancora all’interno degli Eurocodici indicazioni e regole di progettazione per questa tipologia di edifici, soprattutto per quanto concerne la progettazione antisismica. Cionondimeno l’Eurocodice 8 richiede in molti casi, a causa del non soddisfacimento dei criteri di regolarità per la maggior parte degli edifici, l’uso dell’analisi modale con
spettro di risposta, ossia l’analisi dinamica lineare. Questo metodo richiede la stima corretta della rigidezza laterale
dell’edificio al fine di calcolare esattamente le forze sismiche di progetto, che possono essere significativamente
sottovalutate o sovrastimate in funzione delle dimensioni dell’edificio e della forma dello spettro di progetto. A questo scopo è necessario modellare ogni singola connessione basandosi su risultati sperimentali disponibili, che non
sono però facilmente accessibili per un progettista. In questo articolo viene proposto un metodo di progettazione per la modellazione dinamica lineare di strutture in CLT utilizzando SAP 2000. Le formule proposte sono basate
sui riferimenti normativi e bibliografici disponibili, e vengono utilizzate per la progettazione di un caso studio di un edificio di 3 piani. Vengono inoltre presentate ulteriori indicazioni per la progettazione sismica di edifici in CLT che non sono attualmente incluse nell’Eurocodice 8. Infine, il modello di progettazione proposto è anche confrontato
con i risultati di prove sismiche su tavola vibrante condotte su un edificio in CLT di tre piani nel 2006 in Giappone dal CNR-IVALSA.Cross Laminated Timber (CLT) structures are nowadays increasingly used worldwide and mostly in Europe where the system originated. However, in spite of this diffusion which led to the construction of a great
number of multi-storey buildings all over Europe, still Eurocodes are almost completely missing provisions for CLT designers, especially regarding the seismic design. Nevertheless, Eurocode 8 requires in most cases, due to the regularity criteria being not fulfilled for most of the buildings, the use of the modal response spectrum analysis method, i.e. the linear dynamic analysis. This method requires the correct estimation of the lateral stiffness of the building
in order to accurately calculate the design seismic forces in the building, which may be significantly underestimated or overestimated depending on the size of the building and the shape of the design spectrum. This can be done by
modelling each connection with different methods that are often based on available test results, which are not easily accessible by a practicing engineer. This paper provides a design approach for dynamic linear modelling of CLT structures using SAP 2000. Equations are proposed based on available design codes and literature references, and used to design a 3-storey case study building. Further provisions for the seismic design of CLT buildings which are not included in Eurocode 8 are also given. Finally, the proposed design model is also compared with the results of
the shaking table tests conducted in 2006 in Japan by CNR-IVALSA on a three-storey CLT building
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