نتایج جستجو برای ' Cyclic behavior '

Today, sea-going pipelines are mostly non-buried on the sea bed. By changing the flow field around the tube, the sediments under the tube begin to move, and the scouring phenomenon of the bed happens. the presence of roughness in the seabed, leads to the phenomenon of free spans in the pipelines. The simultaneous combination of this phenomenon under cyclic loading is considered as one of the causes of failure of sea pipelines and there is a potential for all kinds of collapses such as yielding a...

Storage tank foundations with frequent discharges and filling or road embankments under repeated traffic loads are examples of foundations subjected to the cyclic loading with the amplitude well below their allowable bearing capacity. The concern exists for the amount of uniform and non-uniform settlement of such structures. The soil under such foundations may be reinforced with geosynthetics to improve their engineering properties. This paper deals with the effects of using the new generation o...

Collapse prevention of structures is one of the main aim in seismic design code. Though, experiences exhibit that most of structures in sever earthquakes receive damages and residual displacements. Such permanent displacements prevents serviceability and in some cases impose repair costs. On the other hand the seismic design of self-centering system exhibits excellent performance regarding the energy dissipation, low damages and minimizing the residual displacements. The use of “hybrid&rdq...

 This study is part of a comprehensive project concerned with research and advocacy of the structural elements containing demolished concrete lumps (DCLs) or demolished concrete segments (DCSs) with a distinctly larger size than the recycled aggregates. Previous studies showed that the steel tubular columns filled with DCLs/DCSs and fresh concrete (FC), recycling demolished concrete in a simplified manner, have properties similar to the conventional concrete filled steel tubular columns. Th...

 An experimental study was performed for batten columns subjected to combination of constant axial compression and reversed cyclic lateral loads to evaluate their cyclic response, available ductility and post failure behavior under seismic conditions. To determine and evaluate the available ductility of batten columns, the backbone curves have been developed using experimental hysteresis curves of columns. The effect of different parameters such as axial compression, distance between batten...

 In this research, 18 laced built-up columns with various geometric specifications were analyzed under different levels of axial load and cyclic lateral load using the finite element method. This research was performed as a continuation of the experimental investigation on the cyclic behavior of the laced columns. This study evaluated the effects of column's geometrical parameters and various levels of axial loads on the cyclic behavior of laced columns. A compression of the results shows t...

 The mechanical models used to simulate the complete behavior of full-scale bolted T-stub connections under cyclic loads are mainly treated in this paper. These mechanical models are composed of individual T-stub components modeled as nonlinear spring elements in order to reliably reproduce their various response mechanisms interacting with one another in the connection. The hysteresis behaviors of the T-stub components including bolt/flange uplift, stem elongation, and relative slip deform...

 The common method of connecting I-beam to box column in the case of moment connections has a main problem, that is brittle fracture of full penetration groove welds of beam flanges to the column. To modify the connection, we have proposed a new detail. In the new geometry of connection, there is a gap between beam end and column face. The moment transfers from beam to the column by two full depth side plates. The tensile force is not directly applied to the column face. Therefore the probl...

 The recent earthquakes have shown that steel moment frame (SMF) with weld connections are so brittle. According to studied, the great damages are due to cracking of the weld between the beam flange and the column face and inducing concentrated stresses in this area. A useful approach to reduce the stress concentration at the panel zone could be using of reduced beam section (RBS). Given the enormous impact of seismic behavior and ductility of the panel zone, RBS moves plastic hinge formati...

 Design philosophy of having weak beam – strong column is recommended almost in all design codes. But in some cases, in prior buildings, this philosophy is ignored. In these structures, during major earthquakes, failure mechanism would begin from columns leading to sever damages. To avoid this event, column in the connection zone must be strengthened to conduct the plastic zone to the beams. There is several ways for strengthening concrete columns and one of the efficient ways is usin...