This paper investigated the effects of seawater curing of concrete made by Micro-Nano Air Bubbles (MNAB) on compressive, flexural and tensile strengths of the concrete. This product will be applicable for rehabilitation or repair of coastal RC structures. In this research, the effect of different combinations of concrete ingredients including 0-100, 25-75, 50-50, 75-25, and 100-0 percent ...

In this paper, the flexural free vibrations of three dimensional micro beams are investigated based on strain gradient theory. The most general form of the strain gradient theory which contains five higher-order material constants has been applied to the micro beam to take the small-scale effects into account. Having considered the Euler-Bernoulli beam model, governing equations of motion are w...

PURPOSE The purpose of the present study was to evaluate the flexural strength of the joint between glass-infiltrated alumina frames and the experimental adjusting agent (MA modifier) that contains alumina and magnesia. METHODS A commercially available adjusting agent (Optimizer), a slurry of alumina powder (Alumina modifier), and a bulk specimen (joint-free alumina) were used as controls. Be...

The usual earthquake resistant design philosophy of ductile frame buildings allows the beams to form plastic hinges adjacent to beam-column connections. In order to carry out this design philosophy, the ultimate bond or shear strength of the beam should be greater than the flexural yielding force and should not degrade before reaching its required ductility. The behavior of RC members dominated...

Castellated beams are generally provided with hexagonal and circular openings in the web portion. However, in view of structural applications, appropriate size and shape of openings in web are always a major issue of concern. Research work carried out in optimizing sizes of castellated beam with hexagonal openings have reported that castellated beams fail mainly by local failure modes and stres...

Polysilicon free-free beam micromechanical resonators based on MEMS technology operating in second and third-mode flexural vibrations have been demonstrated at frequencies as high as 102 MHz with Q’s on the order of 11,500. Via strategic placement of electrodes, and careful determination of the exact support beam attachment locations that minimize anchor loss, these new resonators actually exhi...

in investigation of dynamic specifications of castellated beams, it is necessary to be studied the excitation intensity of dynamic mode shapes for different loading conditions. it is evident that for a specific loading, not all modes of a structure are excited and the structural response depends on the applied loading specifications. in this paper using the finite element method (based on ansys...

This study concerns improvement of flexural stiffness/strength of concrete members reinforced with externally bonded, aluminum-glass fiber composite (AGC) beams. An experimental program, consisting of seven reinforced concrete slabs and seven reinforced concrete beams strengthened in flexure with AGC beams, was initiated under four-point bending in order to evaluate three parameters: the cross-...