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This chapter introduces ultrasonic characterization of dynamic depth-dependent biomechanical properties of articular cartilage. The ultrasound-swelling and ultrasound-elastomicroscopy systems are used, which show potentials for the investigation of the transient deformations of articular cartilage at different depths under dynamic loading. Ultrasound approaches inherently provide non-destructive assessment of articular cartilage. With the miniaturization of the ultrasound probes, these ultrasound techniques can be potentially used together with arthroscopes for in vivo assessment of articular cartilage. Studies suggest that these ultrasound approaches can also be potentially applied for dynamic mechanical assessment of other biological tissues, tissue engineered tissues, biomaterials and non-biomaterials. [ABSTRACT FROM AUTHOR]

The behaviour of CFRP confined concrete column under axial compressive force and the longitudinal constraint mechanism of specimen on different CFRP wrapped ways were studied by tests of three CFRP confined concrete columns and one reference concrete column and by three-dimensional nonlinear FEM (finite element method) analysis. The result indicated that when the axial compressive stress is large than 0.8~0.9 times of peak stress, the lateral expansion deformation of concrete increases rapidly. The longitudinal strain-circumferential strain relationship curve is in linear convergence. There exists strain concentration of the strap wrapped specimens in the place where no CFRP is wrapped. Based on the distribution of the lateral tensile strains εF along the longitudinal axis at different relative stress levels of CFRP confined concrete columns, the whole procedure of axially loaded experiment of specimens can be divided into three phases: elastic stage, elastic-plastic stage, plastic stage. [ABSTRACT FROM AUTHOR]