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Wood–plastic composites (WPCs) are environmentally friendly materials with good weather resistance and low cost. To investigate the feasibility of their use in different environments, a WPC was designed and subjected to a uniaxial compression test at seven temperatures to obtain the failure mode, uniaxial compressive strength, elastic modulus, proportional limit stress, peak stress, and ultimate strain. The results showed the following. The failure modes of the WPC specimens at various temperatures were mainly shear compression failure, double shear failure, and end compression failure. The uniaxial compressive strength and elastic modulus decreased with increasing temperature. Specifically, at temperatures of −60°C, 20°C (normal temperature), and 60°C, the WPC had an average compressive strength of 73.55, 33.7, and 13.51 MPa, respectively, and an average elastic modulus of 7819.11, 6141.71, and 2650.17 MPa, respectively. In terms of the WPC's stress–strain relationship, at a temperature greater than the normal temperature, the WPC had a small peak stress but good ductility; at the normal temperature and below, the WPC had a large peak stress but poor ductility. Based on these findings, the experimental phenomena and characteristic constants were analyzed to establish models of factors that reduce the uniaxial compressive elastic modulus and compressive strength of WPC at different temperatures, to provide a theoretical basis for the mechanical calculations for the application of WPC in various extreme environments. [ABSTRACT FROM AUTHOR]

This paper presents an investigation on the mechanical properties of wood plastic composites under uniaxial stress. Experimental studies of test pieces with tensile and compressive load were performed. Failure modes, stress–strain relationship, and other crucial parameters were recorded and analyzed. The results indicated that brittle failure was the typical failure mode of the tensile test specimens, however, shear‐compression failure and wedge double shear failure were commonly observed for samples under compressive load. Mechanical properties of WPC are better than those of timber according to different national standards. Different analytical models were proposed for evaluating the stress–strain response of the specimens. The fitting between the experimental results and calculations was good. [ABSTRACT FROM AUTHOR]

Aluminum–wood–plastic composite (A-WPC) beams are a novel type of structural components formed by the co-extrusion of a wood–plastic composite (WPC) on the surface of a hot-rolled aluminum plate. In this study, composite beams of three different spans were designed to examine the flexural performance of A-WPC beams. For each group of specimens, the four-point flexural test was conducted to determine and analyze the failure mode, yield load, flexural bearing capacity, strength utilization, deformability, and strain distribution. The results show that when the span–height ratio is low, folding failure occurs on the compression side of the reinforced A-WPC composite beam, whereas when the span–height ratio is large, deformation and cracks occur on the tension side of the reinforced A-WPC beam first. Compared to the specimen with a span–height ratio of 18, the average ultimate load of the specimen with a span–height ratio of 12 was higher(66.75%), while the average deflection at failure was lower(38.03%). Compared to the specimen with a span–height ratio of 12, the average ultimate load of the specimen with a span–height ratio of 6 was higher(65.97%), while the average deflection at failure was lower(43.86%). The strength utilization of the reinforced A-WPC beam is 8.71%–9.26% higher than that of various engineered wood beams, and 3.46%–8.61% higher than that of various glulam beams. Based on these results, this paper proposed a method for calculating the flexural bearing capacity of the A-WPC beam. The calculation and test results indicate that the reinforced A-WPC beam exhibits excellent flexural performance and can be used as a model for composite beam design. • The reinforcement design of composite beam with aluminum–woodplastic​ composite. • The failure modes and experimental characterization of flexural test of reinforced aluminum–wood–plastic composite beam. • The flexural bearing capacity calculation of reinforced aluminumwood–plastic-composite beam. [ABSTRACT FROM AUTHOR]

• Wood structure. • SPF columns. • Columns with hollow cross section. • Combined bending and compression. • Inelastic analysis. A rectangular hollow wood column made of Spruce-Pine-Fir (SPF) lumbers was developed, for the purpose of improving the utilization efficiency of timber. The present work conducted experimental investigations of the columns under centrically and eccentrically compression. A wide range of slenderness ratios of columns and eccentricities of loads was considered to carefully examine the failure modes in columns. The results indicated that combined material failures and buckling failures were observed for the intermediately slender columns under axial compression, while buckling failures were observed for the long columns. The ultimate strength of columns under axial compression significantly decreased with the increase of slenderness ratios. The predicted results by the tangent modulus theory closed to those of experiments. The bending failure, which underwent a pronounced nonlinear process, was the major characteristic of the intermediately slender column with an eccentric compressive load. Typically, the load carrying capacity of columns showed a decreasing trend with an increasing in eccentric ratios. Both the secondary bending and material nonlinearity were important factors that impacted the nonlinear response of the column. An analytical model was proposed for evaluating the load carrying capacity of the rectangular hollow columns under the interaction between compression and bending. There was good agreement between the results of the experiments and calculations. [ABSTRACT FROM AUTHOR]