Hybrid multistory buildings are every day more common in the construction industry. However, there is little understanding of the performance of the hybrid connections. In this research, the static and dynamic response of cross-laminated timber (CLT) composites combined with reinforced concrete (RC), hollow steel profiles and laminated strand lumber (LSL) has been investigated. In addition, the effects of posttensioning stresses as well as distinct types of connectors such as nails, self-tapping screws and self-tapping dowels has been accounted for. After experimental work, numerical modelling for simulating the static and dynamic behavior for these hybrid connections was also investigated. Results indicate that such massive timber composite connections behave reasonably similar to conventional timber connections, except in that inelastic deformations may increase up to 200%. In addition, it has been found that existing hysteretic models like the modified Stewart hysteretic model (MSTEW) fit for modelling purposes except that very asymmetric hysteretic behavior can be found for timber-concrete hybrid connections.

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The effectiveness of seismic dampers to improve the lateral performance of timber structures may be heavily diminished if restrictive lateral drift limits as set by building codes, governs the design of the structure. This paper presents an innovative approach to improve the performance of seismic dampers installed in stiff wood-frame shear walls. U-Shape Flexural Plate dampers with a novel internal restraint system, were installed in a 4880x2475 mm wood-frame shear wall with an Eccentric Lever-Arm System which aimed at amplifying the displacements by transferring them from the shear wall to the dampers. Cyclic tests were conducted to four specimens. Initial test results showed that the presented amplifying system suffered concentrated losses of stiffness at some connections joints reducing its real efficiency. The loss of displacement transmission to dampers was retrofitted, and the results showed a great benefit in terms of resilience for the damped shear wall in contrast with unprotected ones. It was found that this approach provides a feasible solution to enhance the lateral performance of wood-frame structures.

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The mechanical properties of 2219-T87 and 2219-T6 aluminum were determined after soak times from 0 to 300 sec at temperatures from 300 deg F (149 deg C) to 600 deg F (316 deg C). Specimens were tested also at ambient temperatures after a soaking period of 300 sec at temperatures of 200 deg F (93 deg C) to 700 deg F (371 deg C). In general, the tensile strength of the 2219 aluminum alloy decreased with increasing temperature. The tensile properties were not significantly influenced by variations in the soak times used through 500 deg F (260 deg C). At 600 deg F (316 deg C), increasing the soak time affected the strength slightly. For relatively short time exposures, this material can be recommended for load-bearing applications to 400 deg F (204 deg C), at which temperature 70 percent of the ambient temperature strength is still retained. When tested at ambient temperature after exposure to 400 deg F (204 deg C) for 300 sec, 2219-T87 retained approximately 97 percent of its original ambient temperature strength.

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