concrete is one of the most widely used materials in construction industry. many large and important structures such as power plants, bridges, dams and buildings employ concrete as main material. propagation of crack is considered one of the main reasons in failure of concrete structures. the process of formation and crack growth is one of the major and complex issues in concrete, because concr...

A new driving mechanism for direction-controlled motion of nano-scale objects is proposed, based on a model of stretching a graphene strip linked to a rigid base with linear springs of identical stiffness. We find that the potential energy difference induced by the strain gradient field in the graphene strip substrate can generate sufficient force to overcome the static and kinetic friction for...

Syntactic foam is being increasingly conceived for aero engine applications to enhance overall structural reliability under impact loading . Systematic compressive tests without and with lateral confinement are carried out investigate the deformation failure of an epoxy syntactic (ESF) at quasi-static 0.01/s, medium rate 10–100/s high strain rates 500–1100/s gradually increasing temperatures fr...

Novel and highly sensitive static strain interrogation technique is demonstrated, where the sensing element is a fiberBragg grating (FBG) and the light source is a frequency-locked diode laser. Locking the laser frequency to the center of an absorption line (atomic line of potassium in our experiment) eliminates the slow frequency drift of the laser. The stabilized laser source is used to measu...

Strip casting is an emerging technology for flat products; it is based on the concept of near-net shape casting; it holds potential for substantial energy saving and reduction in environmentally undesirable emission. In conventional thermo-mechanical processing, the pinning pressure due to the effects of Nb and NbC on boundary mobility is used to advantage to retard static recrystallisation and...