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• Experimental investigation of CLT-concrete composite connections with steel pads. • Comparison of different methods for determining yield points. • Establishment of analytical models for predicting the load-carrying capacity. Cross-laminated timber (CLT)-concrete bolted connections are crucial components of safe and economical composite structures. This work investigates the mechanical behaviour of CLT-concrete connections comprised of CLT panels, concrete blocks and bolt connectors. Fourteen different configurations were tested under the monotonic loading perpendicular or parallel to the grain. The test results indicated that the bending deformation of the bolts mainly occurred at the interface between the CLT panel and concrete block; some cracking appeared in the adhesive layer of all the CLT panels. When calculating the initial stiffness, the secant modulus between 10% and 40% of the peak force is more reasonable than the secant modulus between the origin and 40% of the peak force. The yield points of the CLT-concrete connections were determined by six different methods, and the results were compared and discussed. Furthermore, an analytical model was developed for predicting the load-carrying capacity of CLT-concrete connections with different failure modes. A comparison with experimental results showed that the proposed model can provide a rational estimation of the load-carrying capacity. The outcomes of this study can provide valuable references for future research and structural design of CLT-concrete composite connections in building construction. [ABSTRACT FROM AUTHOR]

• A novel eucalyptus-based oriented oblique strand lumber (ESWood) was proposed. • Considering various eccentricities, the buckling performance of intermediate ESWood columns was presented. • A calculation approach for predicting the inelastic buckling load of intermediate ESWood columns was introduced. Engineered wood-based products manufactured from fast-growing wood species have gained increasing attraction as the demand for using wood in building constructions continues to grow. An innovative oriented oblique strand laminated lumber called Eucalyptus Strand Wood (ESWood) made from fast-growing eucalyptus is presented in this paper. A series of material tests using small clear specimens were carried out to study the basic mechanical properties of the ESWood, while experiments on full-scale columns were conducted to study the buckling behavior of intermediate ESWood columns under centric and eccentric compression. The failure modes and load-carrying capacity of the columns with various eccentricities were reported and evaluated. Efforts were also made to provide a preliminary calculation approach for predicting the critical buckling load of intermediate ESWood columns under both centric and eccentric compression. Based on the analyses presented in this paper, it appears that the oblique strand lamination of ESWood results in great compactness and strength. Compared with the engineered Spruce-pine-fir, wood scrimber, and Glubam, the ESWood has comparable strength to serve as a construction and building material, especially as structural columns. For intermediate ESWood columns under centric and eccentric compression, buckling was observed as the primary failure mode. As the eccentricity increased, the critical buckling load decreased gradually with increasing critical deflection. To predict the inelastic buckling load, Newlin's formula with either the Newlin-Gahagan approach or Yoshihara approach was adopted. The influence of the yielding stress and critical buckling stress estimation was discussed, and the results show that Newlin's formula with Yoshihara approach provides good predictions for the critical load of ESWood intermediate columns. The presented test results and analyses provide basic knowledge for supporting more applications of such fast-growing eucalyptus-based material in building constructions. [ABSTRACT FROM AUTHOR]

• Failure modes of concrete-CLT connections under cyclic loading. • The mechanical properties of connection are investigated. • The UKF is employed to identify the parameters of SAWS model. • Two assessment methods are proposed to evaluate the estimation results. The mechanical characteristics of concrete to cross laminated timber (CLT) connections plays an essential role in a hybrid structure. This study mainly deals with an experimental and numerical study on the load-slip behaviour of concrete-CLT connections under cyclic loading, where six specimens with two different loading types (i.e., parallel and perpendicular to the grain of CLT) were executed. The failure modes of all specimens were the bolts shear off at the location of the interface between concrete and CLT, associated with the cracking and splitting of CLT panels depending on loading directions. Then the numerical model whose nonlinearity is concentrated on the spring element is created. To calibrate the model parameters, the procedure of parameter estimation using unscented Kalman filter (UKF) is employed to identify the parameters of a hysteresis model. Two assessment methods, including the equivalent energy elastic-plastic curve assessment and an energy-based damage assessment, are used to comprehensively evaluate the estimated result. The model estimate is consistent with the experimental result, demonstrating the identified parameters having good accuracy. The calibrated parameters of a hysteresis model provide a good database when such type of connections are incorporated into a finite element model of a structural system. [ABSTRACT FROM AUTHOR]