Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 93-96). Also available via the Internet.

A timber-concrete composite (TCC) combines timber and concrete, utilising the complementary properties of each material. The composite is designed in such a way that the timber resists combined tension and bending, whilst the concrete resists combined compression and bending. This construction technique can be used either in new build construction, or in refurbishment, for upgrading existing timber structures. Its use is most prolific in continental Europe, Australasia, and the United States of America but has yet to be widely used in the United Kingdom. To date, the topping upgrades used have been 40mm thick or greater. Depending on the choice of shear connection, this can lead to a four-fold increase in strength and stiffness of the floor. However, in many practical refurbishment situations, such a large increase in stiffness is not required, therefore a thinner topping can suffice. The overarching aim of this study has been to develop a thin (20mm) topping timber-concrete composite upgrade with a view to improving the serviceability performance of existing timber floors. Particular emphasis was given to developing an understanding of how the upgrade changes the stiffness and transient vibration response of a timber floor. Initially, an analytical study was carried out to define an appropriate topping thickness. An experimental testing programme was then completed to: characterise suitable shear connectors under static and cyclic loads, assess the benefit of the upgrade to the short-term bending performance of panels and floors, and evaluate the influence of the upgrade on the transient vibration response of a floor. For refurbishing timber floors, a 20mm thick topping sufficiently increased the bending stiffness and improved the transient vibration response. The stiffness of the screw connectors was influenced by the thickness of the topping and the inclination of the screws. During the short-term bending tests, the gamma method provided a non-conservative prediction of composite bending stiffness. In the majority of cases the modal frequencies of the floors tested increased after upgrade, whilst the damping ratios decreased. The upgrade system was shown to be robust as cracking of the topping did not influence the short-term bending performance of panels. Thin topping TCC upgrades offer a practical and effective solution to building practitioners, for improving the serviceability performance of existing timber floors.

Thesis (Ph. D.)--OGI School of Science and Engineering at OHSU, 2001.

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Thesis (M.S.)--Brigham Young University. Dept. of Civil and Environmental Engineering, 2006. / Includes bibliographical references (p. 121-122).

In timber-concrete composite systems, timber and concrete are inherently brittle materials that behave linearly elastic in both tension and bending. However, the shear connection between the members can exhibit significant ductility. It is therefore possible to develop timber-concrete composite systems with ductile connection that behave in a ductile fashion. This study illustrates the use of an elastic-perfectly plastic analytical approach to this problem. In addition, the study proposes an incremental method for predicting the nonlinear load-deflection response of the composite system. The accuracy of the analytical model is confirmed with a computer model, and numerical solutions of the analytical model are compared to experimental results from the bending tests conducted by previous researchers. Reasonable agreement is found from the comparisons, which validates the capacity of the analytical model in predicting the structural behaviour of the timber-concrete composite systems in both elastic and post-elastic stages.

In timber-concrete composite systems, timber and concrete are inherently brittle materials that behave linearly elastic in both tension and bending. However, the shear connection between the members can exhibit significant ductility. It is therefore possible to develop timber-concrete composite systems with ductile connection that behave in a ductile fashion. This study illustrates the use of an elastic-perfectly plastic analytical approach to this problem. In addition, the study proposes an incremental method for predicting the nonlinear load-deflection response of the composite system. The accuracy of the analytical model is confirmed with a computer model, and numerical solutions of the analytical model are compared to experimental results from the bending tests conducted by previous researchers. Reasonable agreement is found from the comparisons, which validates the capacity of the analytical model in predicting the structural behaviour of the timber-concrete composite systems in both elastic and post-elastic stages.

Thesis (M. Phil.)--University of Hong Kong, 2007. / Title proper from title frame. Also available in printed format.

Thesis (Ph.D.)--University of Wyoming, 2008. / Title from PDF title page (viewed on August 5, 2009). Includes bibliographical references (p. 177-184).

Timber-concrete composite (TCC) floor systems consist of a bottom layer of wood that is connected to a top layer of concrete using shear connectors. The shear connectors resist slip between the layers, thus allowing wood and concrete develop composite action when subjected to flexure. The objective of this study is to determine the flexural strength and behavior of TCC floor systems that consist of a cross laminated timber wood layer connected to a concrete top layer using hexagonally headed self-tapping screw shear connectors. To accomplish the objective, coupon specimens and full-scale TCC floor panels were tested, and a finite element modelling approach was developed. The coupon tests were used to determine the stiffness of the shear connection and to determine the effect of the screw configuration. The results from the coupon tests indicated that the inclined screw configuration provided the largest shear strength compared to the normal, crossed, and nested screw configurations. Based on the results from the coupon tests, bending and vibration (heel drop) tests were conducted on full-scale panel specimens with an inclined screw configuration and with a strong-axis panel orientation. The results from the full-scale panel tests showed that the flexural stiffness and strength of the TCC floor system was consistent and that the composite floor panels have adequate stiffness to minimize transient floor vibrations that are caused by walking for typical span lengths and typical loading. A finite element model of TCC floor systems was developed to simulate TCC floor systems and calibrated with the test data. The simulated response matched the test response fairly well for partially composite single-span and double-span panels. Additional refinement of the model is needed to better match fully composite panels. The research demonstrated that hexagonal-headed self-tapping screws may be effectively used to connect wood and concrete layers in TCC floor systems.