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Corrugated panels possess excellent thermomechanical properties, but, with presently no hygrothermal applications for building envelopes, their full potential still needs to be explored. This study characterized the physical properties of three biobased corrugated compositions to identify potential building applications. Flat samples of the same compositions were analyzed for certain properties to aid in understanding. As this characterization is groundbreaking, the testing was based on or inspired by established standards. Results suggest that the panels with two wood veneer cores and two kraft paper surfaces coated with polymers are the most promising, as such structures are less sensitive to water and possess a good moisture buffer value that should be advantageous for building construction. Corrugated panels are particularly interesting because their inner materials have properties comparable to those of conventional wood-based panels such as plywood. However, the apparent properties of corrugated panels become one to ten times smaller or larger, which opens up new design possibilities for building envelope applications.

Corrugated panels possess excellent thermomechanical properties, but, with presently no hygrothermal applications for building envelopes, their full potential still needs to be explored. This study characterized the physical properties of three biobased corrugated compositions to identify potential building applications. Flat samples of the same compositions were analyzed for certain properties to aid in understanding. As this characterization is groundbreaking, the testing was based on or inspired by established standards. Results suggest that the panels with two wood veneer cores and two kraft paper surfaces coated with polymers are the most promising, as such structures are less sensitive to water and possess a good moisture buffer value that should be advantageous for building construction. Corrugated panels are particularly interesting because their inner materials have properties comparable to those of conventional wood-based panels such as plywood. However, the apparent properties of corrugated panels become one to ten times smaller or larger, which opens up new design possibilities for building envelope applications.

A wood-based sandwich panel with a corrugated core was developed as a building material. A matched-die mold manufactured from commercial plywood was used to fabricate the corrugated panels through a cold-forming process. A cold-setting resin was applied on southern yellow pine (Pinus spp.) veneers with an average thickness of 4 mm, and four plies of them were formed into a corrugated geometry using a wooden mold. When the resin was cured, the corrugated panel of veneers retained the corrugated shape after load removal. Facesheets of the sandwich structures were fabricated using three plies of the same veneers. To evaluate the effect of this corrugated geometry on the structural performance, the same veneers — regarding number, thickness, and orientation — used for the sandwich panel were adopted to fabricate laminated flat panels. Both sandwich and laminated flat panels were submitted to a four-point bending test. The results confirmed the sandwich effect, i.e. a 1741% increase in the bending stiffness of sandwich panels compared to that of laminated flat panels. Sandwich panels developed in this study were compared to Structural Insulated Panels (SIPs), wood-framed structures known as stud walls, and sandwich panels produced using a hot-pressing technique. The cold-formed sandwich panels had higher structural performance than commercial building materials.

A wood-based sandwich panel with a corrugated core was developed as a building material. A matched-die mold manufactured from commercial plywood was used to fabricate the corrugated panels through a cold-forming process. A cold-setting resin was applied on southern yellow pine (Pinus spp.) veneers with an average thickness of 4 mm, and four plies of them were formed into a corrugated geometry using a wooden mold. When the resin was cured, the corrugated panel of veneers retained the corrugated shape after load removal. Facesheets of the sandwich structures were fabricated using three plies of the same veneers. To evaluate the effect of this corrugated geometry on the structural performance, the same veneers — regarding number, thickness, and orientation — used for the sandwich panel were adopted to fabricate laminated flat panels. Both sandwich and laminated flat panels were submitted to a four-point bending test. The results confirmed the sandwich effect, i.e. a 1741% increase in the bending stiffness of sandwich panels compared to that of laminated flat panels. Sandwich panels developed in this study were compared to Structural Insulated Panels (SIPs), wood-framed structures known as stud walls, and sandwich panels produced using a hot-pressing technique. The cold-formed sandwich panels had higher structural performance than commercial building materials.

A wooden matched-die mold was manufactured to develop wood-based corrugated panels. Wood veneers brushed with resin were cold pressed between the mold halves and formed into a corrugated geometry. The corrugated panels were used as a core and bonded to flat veneer-based facesheets to develop sandwich panels. The whole manufacturing process involved a cold-forming technique that allowed panels to be produced with no heat. Specimens cut from both corrugated and sandwich panels were submitted to a four-point bending test to evaluate their structural performance. Adopting the same number of layers used to make the sandwich panels, flat panels were fabricated and tested to find the effect of this corrugated geometry and cold-forming process on the load-carrying capacity of the sandwich structures. A comparison with flat panels made with the same stacking of veneers showed an increase of 272% of the bending stiffness of the sandwich panels, which is known as the sandwich effect. Comparison between the bending results of the panels developed in this study with those manufactured using thermoset resin and hot-pressing technique indicated that the cold-forming process using the wooden mold is an effective and inexpensive method to develop wood-based corrugated sandwich panels.

A wooden matched-die mold was manufactured to develop wood-based corrugated panels. Wood veneers brushed with resin were cold pressed between the mold halves and formed into a corrugated geometry. The corrugated panels were used as a core and bonded to flat veneer-based facesheets to develop sandwich panels. The whole manufacturing process involved a cold-forming technique that allowed panels to be produced with no heat. Specimens cut from both corrugated and sandwich panels were submitted to a four-point bending test to evaluate their structural performance. Adopting the same number of layers used to make the sandwich panels, flat panels were fabricated and tested to find the effect of this corrugated geometry and cold-forming process on the load-carrying capacity of the sandwich structures. A comparison with flat panels made with the same stacking of veneers showed an increase of 272% of the bending stiffness of the sandwich panels, which is known as the sandwich effect. Comparison between the bending results of the panels developed in this study with those manufactured using thermoset resin and hot-pressing technique indicated that the cold-forming process using the wooden mold is an effective and inexpensive method to develop wood-based corrugated sandwich panels.

A novel superimposed sine-wave (SSW) structure was designed and fabricated by selective laser melting (SLM) in this work. The energy absorption performance, deformation modes, and fracture mechanism of heat-treated SSW components under compression were studied. The formability was analyzed and the results showed that the SLM fabricated SSW components possessed nearly dense microstructure and smooth surface morphology. The numerical simulation model was established to show the stress distribution and deformation mechanism during compression, and the fracture morphologies of SSW components were investigated. Experimental results indicated that the SSW components exhibited a maximum crush force efficiency (CFE) of 73.06%, which was higher than most reported energy absorption structures. As the height of sinusoid 1 (H1) increased, the energy absorption (EA) and specific energy absorption (SEA) gradually increased to 37.73 J and 8.45 J/g, respectively. Simulation results revealed that the secondary trough had a large deformation during the compression process, which greatly enhanced the load uniformity of the structure. Fracture mode of SSW components was ductile fracture due to the post heat treatment. The SSW structures had the potential to be used in aerospace, protective armor, and automotive industries.