tehran shomal highway passes through alborz mountains with a tunnel length of 6400 meters. there are two main tunnels. a full three-dimensional (3d) numerical analysis coupled with elasto-plastic material models was conducted on the inclined access tunnel. bending moment, axial force and the lining displacements due to the internal forces applied on the shotcrete lining are calculated. axial fo...

Band clamps with a flat bottomed V-section are used to connect a pair of circular flanges to provide a joint with significant axial strength. Despite the wide application of V-band clamps, their behaviour is not fully understood and the ultimate axial strength is currently only available from physical testing. This physical testing has indicated that the ultimate strength is determined by two d...

in fact the most suitable method for finding the load bearing capacity of a member under the axial load or axial load and bending is make use of the interaction diagrams. to analysis and design the hollow circular, square and rectangular high strength concrete (hsc) column shapes, a linear strain variation was assumed in the cross-section height of the members and then the static equilibrium eq...

In this study, experimental study on six RC columns with different slenderness ratios under axial rapid loading was conducted to investigate the axial compression behaviour of RC columns considering the effect of strain rates. The failure pattern of the specimens and the relations of axial loading versus the axial deformation were described. From the test results, the specimens under static and...

Estimation of the nonlinear buckling capacity of thin walled shells is one of the most important aspects of structural mechanics. In this study the axial buckling load of 132 stiffened shells were numerically calculated. The applicability of artificial neural networks (ANN) in predicting the buckling capacity of vertically stiffened shells was studied. To this end feed forward (FF) multi-layer ...

purpose: to evaluate the effect of childhood corneal opacity on the anteroposterior length of the globe in adulthood. methods: twenty-three patients with significant unilateral corneal opacity which had developed before the age of 6 years and the normal fellow eyes (controls) were evaluated. a comprehensive ocular examination including measurement of anterioposterior length and anterior chamber...

Recycled aggregate concrete (RAC) is an environmentally friendly building material. This paper investigates the mechanical behavior of recycled aggregate concrete filled steel tube (RACFST) columns exposed to fire. Two groups of 12 columns were designed and tested, under axial compression, before and after fire, to evaluate the degradation of bearing capacity due to fire exposure. Six specimens...

In this study, the co-operation of steel and concrete in composite columns is considered. Using numerical modeling to study the behavior of these sections, a new type of sections, namely Concrete Filled Double-Skin steel Tubular (CFDST) columns, is introduced. The parameters and techniques that influence the numerical simulation that bring this modeling closer to...