Structural timber-concrete composites

Structural timber-concrete composites (e.g., timber-concrete composite slabs and timber wall-concrete deck composite in which the connection between the two common constmction materials is made through a bonded joint). The aim is to replace traditional mechanical fasteners by an adhesive connection, which has several advantages in comparison with the former for instance, a bonded joint is able to distribute the applied load over the entire bonded joint area, resulting in a more uniform distribution of stress (compared to mechanical point connections), requires little or no damage to the adherends, adds very little weight to the structure, and has a superior stiffness and fatigue resistance. 

Composite rehabilitation systems (CRS), i.e., structural hybrid systems involving advanced polymer composite (APC) materials (generally referred to as fibre-reinforced polymer, FRP), structural adhesives (SA) and conventional construction materials (CCM) (e.g., timber, concrete, masomy, steel, iron), constitute one such technology. 

Advanced fibre-reinforced polymer (FRP) composites for the rehabilitation of timber and concrete structures assessing strength and durability... 

Key words on-site bonded composite systems, repair, reinforcement and seismic retrofit, timber and concrete structures, limitations and requirements, performance and durability. 

The materials, systems/applications and design/regulations presented in the following sub-sections are concerned primarily with the rehabilitation of timber and concrete structures. In spite of this, a brief section is also added to very succinctly discuss the use of composite rehabilitation systems in metallic and masonry structures. 

Structural rehabilitation of timber and concrete structures with composite systems can be generally accomplished in one of two ways (Karbhari and Seible, 2000) using wet lay-up or cured in-situ systems, by application of composite overlays, fabrics, sheets or fibre tows (Fig. 22.4) and using systems involving the bond of prefabricated APC materials, such as straight pultruded strips, and factory-made curved or shaped elements (Fig. 22.5). 

The main applications of composite rehabilitation systems in the rehabilitation of timber structures are described in Table 22.1 and Fig. 22.6, and of concrete structures in Table 22.2 and Fig. 22.7. 

As already evidenced in the above text, currently and at a European level, no well-established design and detailing calculation methods embracing all techniques have been developed for the on-site use of composite rehabilitation systems in timber and concrete structures. Nevertheless, the development of suitable design guidance standards is far more advanced in the case of the rehabilitation of concrete structures than of timber stmctnres. Therefore, for most applications the designers of timber structures composite rehabilitation... 

Structural materials—Materials for foundations can be timber, precast concrete, cast-in-place concrete, compacted dry concrete, grouted concrete, posttension steel, H-beam steel, steel pipe, composite, etc. 

Among the ten EN-Eurocodes, two cover the basis of structural design and the loadings ( actions ), one deals with geotechnical and fotmdation design, while five cover aspects specific to concrete, steel, composite (steel-concrete), timber, masonry, or aluminum construction. Instead of distributing the seismic design aspects to the EN-Eurocodes on... 

In terms of composition, earthquake waste is predominantly construction and demolition waste, that is, waste generated from the demolition of earthquake-affected structures and infrastructure. Waste materials may include metal, concrete, brick, timber, plasterboard, pipes, asphalt, etc. In some cases, where buildings collapse during the earthquake or where buildings are not safe to enter following the earthquake, the waste will include the contents of the building. This could include personal property (e.g., essential documents, money, mobile phones), carpet, furniture, electronic and electrical equipment, plastics, paper, whiteware, putrescible waste, and potentially hazardous materials stored on site (e.g., gas cylinders, oils, pesticides). The exact composition of this waste will depend on the type of building construction and nature of the earthquake impacts. 

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