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The deformation and contact behavior between concrete face and rockfill are important to the safety of concrete face rockfill dams. Based on the monitoring data of Shanxi concrete face rockfill dam, the stress of concrete face, deformation of rockfill and facing joints were studied. It is shown that the rockfill deforms under the water pressure and weight, and the concrete face is compressed in central and otherwise around abutment during the reservoir filling. As the upstream concrete face deforms as the result of the rockfill deformation, the peripheral joints appear tensile, shear and settlement deformation. In addition, the main deformation of peripheral joints is settlement, which has a significant relationship with water level, especially for the upper ones.

Vertically aligned carbon nanotubes (VACNT) arrays were designed to mimic natural foot-hairs of geckos in order to elucidate the adhesion mechanism. We fabricated and systematically investigated adhesive properties of the VACNT arrays with different top structures. Balancing the gas ratio and pressure used for low pressure chemical vapor deposition (CVD) processing controls the top structures of VACNT arrays which determine the strength of adhesion. Their contact behaviors were observed using a scanning electron microscope (SEM). The VACNT arrays attached the target surface by different contact behavior based on the different top structures. The different contact behavior varied adhesive properties of VACNT arrays. VACNT arrays with free top structure present higher adhesion strength due to the side contact with target surface, which indicated that the top structure is an important factor enabling generation of a strong adhesion. These results present clear implications for the role of top structures in VACNT arrays based synthetic gecko systems, which is important for fabrication of gecko-inspired dry adhesives.

The vector form intrinsic finite element (V-5) method and the gap element method are combined to solve the static wheel/rail contact in two-dimensions in this paper to obtain the wheel/rail normal contact pressure, which would be compared with the normal contact pressure of ABAQUS and Hertz theory. The results showed that the contact pressure distribution of V-5 was consistent with ABAQUS and Hertzs, and the mechanical behavior of contact area was reasonable under the circumstance of different axle loads. Besides, it also verified the feasibility of adopting gap elements method to solve the static wheel/rail contact on the basis of vector form finite element method, which with the superiority of large rotation and large deformation, and laid the foundation of rolling wheel-rail contact behavior analysis.

Despite the fact that total knee arthroplasty has become the major treatment for degenerative arthritis, damage to the patellar components remains an unsolved problem as the weight and the postures of a patient keep bringing about stresses on specific points, lines and planes between the patellar and the femoral components and thus lead to the wear and breakage of the former or even an additional knee arthroplasty surgery in a critical situation. To fulfill the need to have an in-depth examination on the contact behavior of the patellofemoral components, the current study conducted in vitro simulation on patellofemoral components with varied designs to mimic different real-life knee flexion angles and to explore the contact behavior in the patellofemoral components. The results of the study showed a higher stability in onlay patellar component when compared to inset patellar component at different knee flexion angles.

The assembly of proton exchange membrane fuel cell (PEMFC) is the important factor for the performance. The achievement of proper design will improve the pressure distribution and the electrical contact resistance between fuel cell parts. The assembly pressure affects the contact behavior between of bipolar plate and gas diffusion layer (GDL). In this study, finite element analysis (FEA) was used to analyze the behavior of single cell fuel cell under the variation of assembly pressure. It shows 3D of deformation, and the compression pressure every part of the fuel cell components. The simulation varied the torque assembly from 1 Nm to 3 Nm with increment 0.5 Nm. The simulation using FEA shows that high assembly pressure also affects to the high deformation and stress in the components of fuel cell. This phenomenon affects to the performance of PEM fuel cell.