The LVL-concrete composite (LCC) structure is a hybrid in system which the LVL member is well connected to the concrete slab by a connector to produce composite action. Various types of connector with different stiffness and shear capacity are available in the market currently. The stiffness of the connector is identified through the push-out experiment. The notch connections for LVL concrete composite beams have higher stiffness and strength compared to mechanical fasteners. This paper discusses the experimental results of symmetrical push-out tests on 3 different types of connector, 150mm rectangular notch with 10mm diameter screw, 100mm rectangular notch with 8mm diameter screw and 100mm triangular notch with 8mm diameter screw. The experimental test was shear push out to failure and the type of failure was discussed. The 150mm rectangular notch was found to be strongest among all and low cost. The 100mm rectangular notch was found to be slightly stiffer than 100mm triangular notch but 100mm triangular notch is easier to construct with only 2 cut. The maximum strength and stiffness at ultimate limit states and serviceability limit states of each type of connection were discussed in this paper.
As part of its research work on wood buildings, FPInnovations has recently launched a Design Guide for Timber-Concrete Composite Floors in Canada. This technique, far from being new, could prove to be a cost-competitive solution for floors with longer-span since the mechanical properties of the two materials act in complementarity. Timber-concrete systems consist of two distinct layers, a timber layer and a concrete layer (on top), joined together by shear connectors. The properties of both materials are then better exploited since tension forces from bending are mainly resisted by the timber, while compression forces from bending are resisted by the concrete. This guide, which contains numerous illustrations and formulas to help users better plan their projects, addresses many aspects of the design of timber-concrete composite floors, for example shear connection systems, ultimate limit state design, vibration and fire resistance of floors, and much more.
In this paper a novel and efficient structural system, that comprises steel beams and prefabricated timber slabs is developed and tested under short-term service and ultimate limit state loading conditions. In the proposed steeltimber composite (STC) system, bolt and coach screws are employed to transfer shear between steel beam and prefabricated timber slab and provide a composite connection. A series of experimental push-out tests were carried out on cross-banded LVL-Steel and CLT-Steel hybrid specimens to investigate the behaviour of different connection types. Furthermore, the load-deflection response of full-scale STC beams was captured by conducting 4-point bending tests on STC beams. The failure modes of connections and composite beams have been monitored and reported. The results illustrate advantages of using timber panels in conjunction with steel girders in terms of increasing strength and stiffness of composite beams
This paper presents the development of two new types of hybrid cross-laminated timber plates (HCLTP) with an aim to improve structural performance of existing cross-laminated timber plates (Xlam or CLT). The first type are Xlam plates with glued timber ribs and the second type are Xlam plates with a concrete topping. A numerical...
This thesis investigated light-frame wood/concrete hybrid construction as part of the NSERC Strategic Network on Innovative Wood products and Building Systems (NEWBuildS). A review of eight wood/concrete niche areas identified three with potential to be used in mid- to high-rise structures. Light-frame wood structures of seven or more storeys with wood/concrete hybrid flooring seem to have little feasibility unless a concrete lateral-load-resisting system is provided and material incompatibilities are solved. Non-load-bearing light-frame wood infill walls in reinforced concrete frame structures were recognized to have potential feasibility in mid- to high-rise structures. A full-scale, single frame test apparatus was successfully designed and constructed at the Insurance Research Lab for Better Homes. The frame is statically loaded to accurately replicates realistic horizontal sway and vertical racking deformations of a typical eight storey reinforced concrete frame structure at SLS and ULS. A linear-elastic analysis of the test apparatus was generally able to predict the results during testing. The 2.4m x 4.8m (8 ft. x 16 ft.) infill wall specimen did not satisfy serviceability deflection limitations of L/360 when subjected to representative out-of-plane wind pressures of +1.44/-0.9 kPa. The out-of-plane response was not significantly affected by horizontal sway deflections of +/-7.2mm or vertical racking deflections of +9.6mm. Although a nominal 20mm gap was provided to isolate the wall from the surrounding frame, insulation foam sprayed in the gap facilitated load transfer between them.