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This study focused on the mechanical performance of toothed metal-plate connected (MPC) laminated bamboo lumber (LBL) joints aiming to apply this metal-plate connection to the design and manufacturing of engineered bamboo trusses, due to the merits of the cost-effective and easy installation. A total of 212 MPC LBL and SPF (spruce-pine-fir) joints connected by the domestic toothed metal plates were tested in accordance with Chinese standards. Particular emphasis was placed on the load-slip behavior of metal plate teeth embedded in LBL with varied load direction related to the major axis of the toothed metal plate. Design values of the tensile and shear strength of the net section cross metal plate connector, and the anchorage and anti-slip strengths of the metal plate teeth embedded in LBL were presented in accordance with the existing timber design specification. Test results reveal that the metal plate orientation has a significant effect on the mechanical performance of MPC LBL joints. A new angular equation, expressed as the metal plate orientation, was proposed for evaluating the anchorage and anti-slip strengths of MPC LBL joints, which shows an obvious reduction in predicting error compared with the existing method. Design strength values of LBL joints are higher than those of the corresponding SPF joints, mainly due to the relatively smaller dispersion of LBL compared with SPF, indicating that the MPC LBL is expected to replace MPC timber in truss systems. The results of the comparison of MPC LBL and glubam (glued laminated bamboo) joints also suggest that arranging transverse bamboo strips is an available option for improving the anchoring mechanical performance of MPC LBL joints. • Total 212 MPC LBL and SPF joints connected by the domestic toothed metal plates were tested for developing engineered bamboo trusses. • Design strength values of LBL joints are higher than those of the corresponding SPF joints, indicating that the MPC LBL is expected to replace MPC timber in truss systems. • A new angular equation was proposed for evaluating the anchorage and anti-slip strengths of the MPC LBL joint. [ABSTRACT FROM AUTHOR]

• A total of 95 glubam joints with single glued-in GFRP rod were tested in a pull-pull tension loading program, aiming to shed light on the test parameters on the mechanical behavior. • Particular emphasis was placed on the initial stiffness analysis and the explanation of the bond-slip mechanism based on the strain distribution of GFRP rod. • Both strength and stiffness models are proposed for evaluating the bond strength and the initial stiffness of glubam joint with glued-in GFRP rod. Fiber reinforced polymer (FRP) rod is a reasonable alternative to steel rod used in glued-in rod engineered bamboo structures, mainly attributed to its significantly higher strength-weight ratio and excellent corrosion resistance, while this field of study is almost empty. To fill this research gap, a total of 95 glued laminated bamboo (glubam) joints with single glued-in glass FRP (GFRP) rod were tested in a pull-pull tension loading program, aiming to shed light on the influence of anchorage length, rod diameter, bonding length-diameter ratio, glue-line thickness and rod-to-grain angle on the mechanical behavior. Particular emphasis was placed on the initial stiffness analysis and the explanation of the bond-slip mechanism based on the strain distribution of GFRP rod. Approximately 30% and 65% of the glued-in glubam joints can be categorized as the pure bonding failure at the glubam-adhesive interface and the shear failure in the glubam, respectively. It is found that the shear strength and initial stiffness of glubam joint decrease with increasing of the bonding length, the bonding length-diameter ratio, and the glue-line thickness, but the two indexes increase with increasing of GFRP rod diameter. The shear strength and initial stiffness exhibit an initial upward and then downward trend when the rod-to-main fiber direction angle varied from 0° to 90°. The analysis results reveal that the distribution of the local slip stiffness is non-uniform along the bonding length, also meaning that the local bond-slip relationships are varied at different locations. Based on the single-parameter correlation analysis, a strength model and an initial stiffness model are proposed for predicting the mechanical performance of glubam joints with glued-in GFRP rod for a potential application in evaluating actual glubam joints. [ABSTRACT FROM AUTHOR]

• A novel structural nail-laminated panel constructed of engineered bamboo and local fast-grown Chinese fir was proposed in this study. • Static bending tests were performed on twelve nail-laminated bamboo and timber (NLBT) specimens. • This research provides a feasible and reasonable approach for developing local fast-grown species as structural components. This study attempts to develop a novel structural nail-laminated panel constructed of engineered bamboo and local fast-grown plantation Chinese fir. An experimental program is reported in this paper on static bending behaviors of such nail-laminated bamboo-timber (NLBT) panel. Twelve NLBT specimens, including five short span specimens without butt joints and seven long span specimens with different butt joints were manufactured and tested. The panel span, species of sawn timber boards, the cross sectional configuration, and reinforcement measures of butt joints were chosen as the experimental parameters in the current investigation. The typical failure mode of the short span NLBT panels exhibited a multiple-fracture process caused by the tension failure of timber layers, while the overall collapse was much delayed or avoided attributed to the residual bending capacity provided by glubam layers. Test results demonstrate that the use of fast-grown Chinese fir instead of imported dimension lumber to combine glubam does not obviously reduce the bending performance of NLBT panels. The proposed vertical nailing reinforcement for butt joints can significantly improve the bending stiffness of the long span NLBT panels, and it is convenient for processing and assembling of NLBT components. Based on the ratio of bamboo and timber, a simple linear relationship is proposed for predicting the elastic modulus of the NLBT through regression analysis. The observed performance evaluation also reveals that the bending performance of the proposed NLBT structural panels is sufficient to meet the design requirements for using as the structural floors in offices and residential buildings. This research provides a feasible and reasonable approach for developing local fast-grown species as structural components. [ABSTRACT FROM AUTHOR]