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The design and modelling of 10-, 15-, and 20-storey wood buildings with cross-laminated timber and glulam structural members are presented in the present study. The system is platform-type construction with a cross-laminated timber core, perimeter walls as lateral load resisting system, and glulam columns as the gravity system. The designed buildings satisfy requirements stipulated in applicable design codes in Canada. The hysteretic models and the associated parameters used to model the fasteners for wood members are developed. Assessments of the nonlinear inelastic seismic responses and capacity curves of the designed buildings are carried out using the incremental dynamic analysis (IDA) and nonlinear static pushover analysis (NSPA) methods. The results indicate that the NSPA curve closely approximates the mean capacity curve estimated using the IDA curves for wood buildings. The post-yield stiffness ratio to initial stiffness for the wood buildings ranges from approximately 0.35 to 0.55. The results also show that the effect of the record-to-record variability on the IDA curves is substantial. Key words: capacity curve, cross-laminated timber, hysteretic model for the connectors, inelastic responses, seismic excitations. La conception et la modelisation de batiments en bois de 10,15 et 20 etages avec bois lamelle-croise et elements de charpente en lamelle-colle sont presentees dans la presente etude. Le systeme est un type de construction a plateforme avec un noyau en bois lamelle-croise, des murs de perimetre comme systeme de resistance a la charge laterale et des colonnes en lamelle-colle comme systeme de gravite. Les batiments concus satisfont aux exigences stipulees dans les codes de conception applicables au Canada. Les modeles d'hysterese et les parametres associes utilises afin de modeliser les attaches pour les elements en bois sont elabores. Les evaluations des reponses sismiques non lineaires non elastiques et des courbes de capacite des batiments concus sont effectuees a l'aide des methodes d'analyse dynamique incrementale (<>) et d'analyse statique non lineaire (<>). Les resultats indiquent que la courbe NSPA se rapproche de la courbe de capacite moyenne estimee a l'aide des courbes IDA pour les batiments en bois. Le rapport de la rigidite post plasticite et la rigidite initiale des batiments en bois varie entre 0,35 et 0,55. Les resultats montrent egalement que l'effet de la variabilite d'un enregistrement a l'autre sur les courbes IDA est considerable. [Traduit par la Redaction] Mots-cles : courbe de capacite, bois lamelle-croise, modele d'hysterese pour les assemblages, reponses inelastiques, excitations sismiques., Introduction Wood is a construction material traditionally used for houses and low-rise buildings. Engineered wood composites such as structural composite lumber, laminated veneer lumber (LVL) and cross-laminated timber (CLT) could [...]

The strength and stiffness of wide flange beams to rectangular tube column joints are reduced significantly if the connections are not reinforced. However, the reinforcement for the connections can be complex and increase the fabrication costs significantly because the tube columns are closed sections. This paper describes the force transfer mechanism and the cyclic performance of wide flange beams to square concrete-filled tube column joints reinforced with stiffening plates around the column. The first phase of this research program was to assess the force transfer mechanism at the joint using an analytical yield line method. An experimental program was conducted to verify the proposed model. The test results showed that the derived nominal strength equation provided a reasonable prediction. As the second phase of the research program, full-scale joint subassemblage tests were conducted to assess the cyclic performance of the joints. A total of seven specimens were tested under cyclic loading. Test results showed that total rotation of 0.04 rad which is required for special moment resisting frames could be obtained. CE Database subject headings: Experimentation; Steel beams; Joints; Concrete; Steel plates; Tubes.

A series of tests is performed on composite beams with web openings. The beams have ribbed slabs with the ribs oriented transversely. The effects of slab width and moment-shear ratio on failure mode and strength are studied. Failure mode of concrete slabs depends on the slab width. Pullout failure around the shear connectors at the high-moment end occurs in the beams with wide slab width, while diagonal tension-type failure occurs in a beam with narrow slab width. Based on the test results, a strength model is developed. The maximum shear capacity is approximated as the sum of the individual shear capacity of the steel beam and the concrete slab. The shear contribution of the concrete slab is taken as the lesser of the shear strength of the slab and the pullout capacity of the studs. Strength predictions of the proposed model are compared with test results and predictions of other strength models. The proposed model is easy to use and gives satisfactory predictions. CE Database subject headings: Composite beams; Slabs; Failure modes; Ultimate strength; Webs.

A new hot-forming process has been studied to produce anisotropic Nd-Fe-B-based magnets from melt-spun ribbons. The ribbon fragments were inserted in a Cu tube and hot-deformed together with one-stroke. At a height reduction ratio of 0.44, the melt-spun ribbons were densified into a magnet with a density of 7.14 g/[cm.sup.3], and showed a [(BH).sub.max] of 14.6 MGOe. With further deformation, the magnets were plastically deformed with Cu tubes in the lateral direction, and crystallographic anisotropy was introduced. The magnets with a height reduction ratio of 0.75 exhibited magnetic properties of [(BH).sub.max] = 32.1 MGOe, [B.sub.r] = 11.7 kG, and i[H.sub.c] = 10.6 kOe. This process shows the possibility that the conventional hot-pressing and subsequent die-upsetting for anisotropic magnets can be simplified into a one-step process.

The two morphologically distinguishable forms of finless porpoise (genus Neophocaena) are studied to demonstrate the significance of studying the recent speciation events in for understanding the Earth's biodiversity. The two forms are shown to exhibit completely different genetic characteristics and hence are considered as two different species.