Glulam beams reinforced with FRP strips and their application in architecture

Abstract

This paper emphasizes the advantage of using carbon polymers while producing and strengthening glulam beams. Due to advanced research carried out in this field, the first application of carbon polymers based products was implemented in Western countries. Structural elements containing carbon polymers, or being reinforced by them, show higher resistance and durability properties, as well as the ability to be produced in various shapes. These features can find best application in architecture so the architects? imagination in design could be realized. Many attractive buildings were constructed over the last decade, each of them showing exceptional safety, resistance to atmospheric influences, durability and cost-efficiency. Beside application of carbon polymers in the construction of new buildings, they are even more important in the field of historic heritage restoration. The original research carried out on ten samples in the laboratory is presented in the second part of the paper. Position of the reinforcement on the samples was chosen as it would be done in practical retrofit cases. Deformations of the samples exposed to pure bending were measured, so their behaviour in the elastic range could be analysed based on the results. Measured results were compared to those calculated by using FEM model, developed with software package AxisVM. Based on performed analysis, the conclusion was made that by strengthening timber glulam beams with FRP strips, the simple and efficient static load bearing capacity upgrade is gained.

Behavior of glulam timber beam strengthened with carbon fiber reinforced polymer strip for flexural loading

“…Additionally, other studies have reported results on the condition of FRP sheets placed in slits from the outside. [21][22][23][24][25] Nowak et al 23 conducted a study with CFRP sheets embedded in lateral slits in the tensile zone; three sheets were inserted on each side, and an approximately 21% increase of the flexural capacity was obtained, with a significant increase of the midpoint deflection and plastification area of the beam. Nowak et al 24 reported up to 19% improvements in flexural load capacity by expanding these results for the case of reinforcement vertically inserted in slits.…”

“…When the literature is examined, many studies on wooden beams are formed as solid, 5,8,[13][14][15][16][17][18][20][21]24,[30][31][32] and there are many scientific studies in this area. When examined in Table 1, 4,13,19,22,25,29,34 glulam wood layers, which are more preferred in practice and less in academic studies, draw attention. Seven 27 and ten 33 glulam wood layers are less preferred, and as the number of layers increases, the weakness points at the interfaces increase.…”

Enhancement of bending properties of Douglas-fir and poplar laminate veneer lumber (LVL) beams with carbon and basalt fibers reinforcement

“…Furthermore, previous works have demonstrated the importance of the quality of the wood used in laminated lumber under bending stresses [15]. The use of carbon and basalt fiber reinforced polymers (CFRP and BFRP, respectively) has been studied in sawn wood and technological products such as glulam and LVL elements, demonstrating the improvement of mechanical properties under different reinforcement configurations [16][17][18][19][20][21][22][23][24][25].…”

Acoustic Emission and Numerical Analysis of Pine Beams Retrofitted with FRP and Poplar Wood

“…Many of the existing wooden structures are made of pine, being the Pinus Sylvester widely used in many areas of the Iberian Peninsula. For several decades, many works have demonstrated the enormous advantages of FRP (fiber reinforced polymer) composite materials for retrofitting and repairing of structural elements (mainly beams) of concrete or timber, whether embedded in the structural element by means of artificially grooves (near-surface mounted technique), or externally applied (usually on the tension face but also on lateral sides of the element for shear reinforcement) [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16].…”