Self-camber of timber beams by swelling hardwood inlays for timber–concrete composite elements

A new concept of bio-based prestress technology with experimental Proof-of-Concept on Bamboo-Timber composite beams

“…There is a need to find a new route to prestress bio-based materials in construction. Despite several interesting research attempts [15][16][17][18][19], the prestress technology for pure bio-based material is still far from mature and very few practical projects have adopted this technology.…”

“…Apart from the above attempts following the conventional approach, there are a few recent new studies that focused on developing alternative, pure bio-based prestress technology. By using moisture induced expansion of a series of compression wood inserts preinstalled in the pre-cut slots or holes to generate the prestressed (or pre-camber) conditions [15][16][17][18][19], these studies are the first laboratory attempts to develop pure bio-based prestress technology for timber beams. However, the uncertainty of moisture level during the regular service of a building and the damage to the structural integrity for accommodating the wood inserts are among the key obstacles preventing the application of this technology in practical engineering.…”

Application of Graphic Statics and Strut-and-Tie Models Optimization Algorithm in Innovative Timber Structure Design

“…(b) Embedding dried hardtimber inserts into notches or slots milled on the top surface of timber elements, causing them to form curves. These inserts expand as they adjust to the moisture content (MC) and climate of the surrounding timber, creating pre-stress forces [11]. This approach compromises the mechanical performance of timber components from the outset.…”

Densified delignified wood as bio-based fiber reinforcement for stiffness increase of timber structures

“…It possesses a higher tensile strength (≈135 MPa) but an only moderately higher tensile stiffness (≈14 GPa) at the clearwood (defect-free) scale compared to more wellestablished wood species such as Norway spruce (Picea abies) (≈95 MPa; ≈11 GPa) [3]. Particularly for the application as timber products such as glued-laminated timber (GLT), e.g., for timber-concrete composite (TCC) slabs, the design is specifically limited by SLS deflection criteria [4,5]. Therefore, the use of beech wood would lead to oversizing of the required cross-section in terms of ULS.…”