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This paper illustrates static and free vibration analysis of a cross-ply laminated composite plate embedded in piezoelectric layers based on three dimensional theory of elasticity. In this approach, a semi-analytical solution is presented for the hybrid plate with arbitrary boundary condition. For analysis a differential quadrature method (DQM) is used in two directions and state space method is employed along the thickness direction. The method is validated by comparing numerical results with the one obtained in the literature and also the results of DQM are compared with the results of analytical solution obtained by Fourier series solution. In parametric study, the effect of boundary condition, mechanical load, electric voltage, length to thickness ratio and piezoelectric thickness on both vibration and static behavior of plate are investigated. [ABSTRACT FROM AUTHOR]

This paper presents experimental and analytical studies on trusses made of glue-laminated bamboo or glubam, which is a new type of structural material unlike conventional steel or timber. Six full-scale model trusses with two types of configurations and sizes were tested to failure under gradually increased vertical load. The failure of the model trusses was caused by lateral buckling of the top compressive chords. Tests show that the model glubam trusses have adequate stiffness and strength. Analyses were also conducted to model the truss behavior with considering different joint conditions, such as pinned, rigid as well as semi-rigid joint using fictitious members. The analytical results for deformation at the design load level agree with the test results favorably well using all types of joint models. The semi-rigid joint model provides a slightly better prediction to the load carrying capacities of the model trusses. However, the analytical truss model based on pinned joints generally provides conservative prediction to load carrying capacities. [ABSTRACT FROM AUTHOR]

Three series of AlO/Al laminated ceramic matrix composites, named SPA, SPV and HP, were fabricated by different methods. SPA and SPV were prepared using AlO slices and Al slurry via screen printing and subsequent heat treatment in air or vacuum. HP samples were made by hot pressing the layered stack of Al foils and AlO slices. SEM and XRD were applied to analyze the microstructure and the interlayer crystal phase. The bending strength, fracture toughness and fracture work of the samples made by the three methods were measured and compared. The results show that the composites have much better toughness and higher fracture work than the AlO slice. Among the samples made by the three methods, the samples made by hot pressing have the optimum mechanical performance. The displacement-load curves and fracture mechanism were analyzed. [ABSTRACT FROM AUTHOR]

Lightweight laminated composites containing a ceramic front layer and a metallic backing layer were used in order to protect people, moving equipment, and mobile vehicles from high velocity impact and the increased mobility of mobile vehicles. In this study, by adding10 vol% SiC and 500 ppm MgO nanoscale particles on the microstructure of Al O matrix and applying optimum sintering conditions, ceramic performance against high-speed projectile impact was improved. To perform this investigation, a number of target samples with two different types of front layers (alumina and Al O- SiC- MgO nanocomposite ceramic) were produced. Impact tests were conducted on these samples using 7.62 mm projectiles with a velocity of 820 ± 15 m/s. The amount of bulge and bending of the backing layer caused by impact tests was measured. The results of the impact tests on the samples made of Al O- SiC- MgO nanocomposite ceramics and alumina were also compared and analyzed. The results indicate that the substitution of Al O- SiC- MgO ceramic layer - which is proffered in this paper - instead of pure alumina ceramic layer, decreases the areal-density of the samples by at least 30% and improves mechanical properties by about a 60% increase in flexural strength and 100% growth of the energy distribution factor, which impressively increases impact energy absorption. [ABSTRACT FROM AUTHOR]

The influence of structural configuration on vibration responses of smart laminated beams under random loading is studied. The effect of laminate configurations and locations of sensors/actuators in the smart system is also investigated. The layer-wise approximation for displacement and electric potential is utilized to construct the finite element model. The closed-loop control response is determined through an optimal control algorithm based on the Linear Quadratic Regulator (LQR). The correlation coefficient between the input random force and the applied actuating voltage for various configurations is also computed. It is revealed that for softer configurations, the correlation coefficient is higher than that for harder configurations. The study on the effect of sensor/actuator collocation pairs on optimal vibration control reveals that as the actuator shifts away from the sensor location, the peak of power occurs at higher frequency and becomes more distributed through all the frequencies in the domain. [ABSTRACT FROM AUTHOR]

Laminated ZrB2/Mo composites, alternately consisting of matrix layers of 80 vol.% ZrB2 + 10 vol.% nano-SiC whiskers + 10 vol.% SiC particles and Mo interlayers, with the addition of Si and B as interlayer adjusting agent, were prepared by roll-compaction and spark plasma sintering (at 1600°C) process. XRD and SEM techniques were used to characterize the phases and microstructure of the obtained composites. The results showed that without the addition of Si and B in the interlayer, interfacial debonding between the matrix layer and interlayer often occurred due to the thermal mismatch between the two kinds of layers. However, the interfacial mismatch could be effectively inhibited by the addition of Si and B to the Mo interlayers. The laminated ZrB2/Mo composites with 6 at.% Si and 4 at.% B in the interlayers showed the highest bending strength at (451±20) MPa and the highest fracture toughness at (7.52±0.12) MPa·m½. MoB, ZrB and Mo5SiB2 were formed by the reactions among ZrB2, Mo and the additions. [ABSTRACT FROM AUTHOR]

By using the methods of asymptotic splitting, the 3D problem on the transverse-longitudinal bending of elastic anisotropic laminated bars under the action of longitudinal and transverse loads is split into a number of plane boundary-value problems, whose solution allows one to construct asymptotic approximations for all components of the displacement vector and the strain tensor at each point in the bars. A system of ordinary differential equations of transverse-longitudinal bending is obtained for laminated bars with arbitrary anisotropy of its layers. A condition for the edge compatibility of materials in laminated orthotropic bars is deduced. [ABSTRACT FROM AUTHOR]

The article examines a study related to symmetrically laminated composite plates on elastic foundation. According to the study, classical theory of plates (CPT) assumes that plane sections initially normal to the mid surface before deformation remain plane and normal to surface after deformation. It was inferred that bending analysis of cross-ply rectangular thick plates resting on elastic foundation has been done by using first order shear deformation theory.

Equations governing deformation of an elastic inhomogeneous laminated body of revolution are proposed. Each layer is a domain bounded by convex equidistant surfaces of revolution. [ABSTRACT FROM AUTHOR]