Introduction to the use of wood in construction
The use of sustainable building materials including wood, recycled steel and aluminium, rammed earth and biodegradable plastics has increased in recent years, with many builders favouring wood as a preferred material. Wood is a highly sustainable building material that has been used for thousands of years. It has a high strength-to-weight ratio, making it ideal for buildings in active seismic zones. Furthermore, wood provides better sound and thermal insulation, it is readily available in urban areas and is fire resistant.
Prefabricated timber-concrete composite flooring is one popular way of using wood in construction. This method combines the advantages of both materials, with timber frames and trusses providing tension zone strength and concrete providing compression zone strength, connected by shear connectors. This design has several advantages, including being lighter than concrete beams and having greater timber durability than timber bridges.
Overview of the timber-concrete composite flooring method
Previous research has primarily focused on assessing the system’s performance using various types of timber products, including glulam, solid timber, laminated veneer lumber, cross-laminated timber, and built-up joists. Adhesives, screws, punched metal plates, notched connections, steel mesh connections, or a combination of these connections are commonly used to connect the timber to the concrete (hybrid systems).
Common methods used to connect timber to concrete
Metal dowel-type fastener connections were used in approximately 45% of previous studies to increase bending stiffness and reduce joist self-weight. The solid wood joist is replaced by a variety of built-up section joists, including the I-shaped joist, box-shaped joist, and open web truss joist (OWTJ). When compared to other built-up sections, the OWTJ appears to be the most promising in terms of load-bearing capacity. The OWTJ converts the bending and shear forces developed in the floor into truss action.
The advantages of using prefabricated elements in the system
The use of concrete materials in the timber-concrete composite floor is a novel approach to achieving a structure with high bearing capacity and stiffness. Furthermore, the use of prefabricated elements can simplify material transportation and construction, providing numerous benefits such as quick and easy installation, low production costs, no waste materials, and improved quality.
Conclusion and recommendation for the use of timber as a support for concrete floors
To support sustainable development, high-performance residential buildings must be built. Despite advances in timber technology, the use of low-strength timber as a construction material to address the housing and infrastructure shortage has yet to be implemented. It is suggested that a prefabricated composite floor system made of fast-growing timber be used in low-rise buildings.
Paraserianthes falctaria is a fast-growing wood species that can be used to support the prefabricated concrete slab floor in the OWTJ system. Lag screws connect all elements of the system. The use of this composite floor can significantly speed up the building construction process.