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Using a two‐step molding process, wood plastic composite (WPC) were prepared under temperatures ranging from 160 to 180°C. Uniaxial compression tests of WPC were conducted at temperatures of −20°C, 0°C, 20°C, and 40°C, determining stress levels of 30%, 45%, and 60% based on the test results. Subsequently, 24‐hour compression creep tests were performed for WPC under 12 different conditions. The Findley power law model was employed to fit the experimental results, indicating that creep deformation increased with both stress level and environmental temperature. Notably, specimens at 0°C failed after sustaining a load for 13.6 hours at 60% stress, while those at 20°C failed after only 0.72 hours under the same conditions. Overall, the Findley model effectively predicted the creep behavior of WPC under all temperature conditions and stress levels. Highlights: The influence of temperature variation on the strength of WPC.Short term creep of WPC under different stress levels.Creep of WPC at different temperatures.Prediction of creep performance under different operating conditions. [ABSTRACT FROM AUTHOR]

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]

Five specimens were cut from an aluminum alloy thin-walled hollow column to complete a tensile test, and the strength of the aluminum alloy was measured to be 200.18 MPa. The Ramberg–Osgood model was compared with the stress-strain relationship of the test results, and the fitting regression coefficient was more than 0.99. Four groups of axial compression trials of aluminum alloy thin-walled hollow columns with different heights were accomplished, and the test phenomena and data were concurrently observed and recorded. The results show that the axial compressive bearing capacity of aluminum alloy thin-walled hollow columns does not change with the change in column height, the mean value is 73.72 kN, and the corresponding covariance is only 2.14%. Local buckling failures appeared in all of these columns, and the failure locations were distributed at each height of the test pieces. The stiffness of the column decreased with the increase in height and width ratio, and the varying trend between them obeys exponential distribution. The displacement that corresponds to the ultimate load increased with the increase in the height-width ratio, and the increasing trend follows a linear relationship with the change in column height. [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]

Bamboo fiber (BF) possesses advantages such as environmental friendliness, renewability, economic viability, and favorable mechanical properties, making it a promising material for improving the brittleness and tensile strength of concrete. Previous investigations have demonstrated a limited exploration of BF-reinforced lightweight aggregate concrete (LWAC). Current study concentrates on investigating the mechanical properties and stress-strain relationship of BF-reinforced LWAC. To achieve this, 7 groups of BF-reinforced LWAC specimens were subjected to compressive tests, splitting tensile tests, and prism compressive tests. The influence of BF content and length on the compressive performance, failure modes and stress-strain curves was studied. BFs effectively suppressed the development of internal cracks in LWAC, playing a role in crack resistance and toughness enhancement. Furthermore, BFs significantly improved the splitting tensile strength of concrete, while the compressive strength slightly decreased with the increase of BF content. After adding BFs, the splitting tensile strength of concrete increased by 8.2∼23.7%, and the compressive strength decreased by 3.6∼11.1%. Moreover, the BF length had almost no effect on the compressive strength of concrete, while when the BF length was 10–30 mm, the tensile strength increased by 5.3∼17.6%. Based on existing researches, strength conversion equations and stress-strain constitutive models of BF-reinforced LWAC were proposed, and the models provide a theoretical basis for the calculation and analysis of BF-reinforced LWAC components and structures. • Bamboo fiber (BF)-reinforced lightweight aggregate concrete (LWAC) was examined. • BFs significantly improved the splitting tensile strength and ductility of LWAC. • The failure modes of specimens were analyzed based on SEM images and DIC technology. • The stress-strain models of BF-reinforced LWAC were established. [ABSTRACT FROM AUTHOR]