Search results

Introduction For a moderate earthquake prone area, many reinforced concrete frame buildings have been constructed without seismic consideration.
Nevertheless, hollow thin section steel column can be locally bucking leading to unfair inelastic behavior.
Behavior of the tested columns under cyclic loading can be quantitatively obtained through the consideration of load-displacement response.
Figs.3 show the effect of concrete filling on the behavior of specimen R100 under uni-axial cyclic loading.
For failure behavior, all specimens experienced local biaxial buckling.

The evaluations that have been conducted on gravity frames have generally been undertaken on gravity frame subassemblies, (columns, beams, and connections) to evaluate their flexural behavior.
There are several types of beam-column connections in gravity frames of steel structures.
WSP compressive axial behavior under different level of shear force Lateral drift effect.
Lateral bracing of beam web and bottom flange Packing effect.
Stability functions use the general stiffness matrix considering the effect of axial load on member stiffness.

Diagonal bracing members was found effective in resisting lateral forces in early designs of tall building.
The core of the building has only little effect on Hexagrid, it is a self reliant structure.
The advantages of hexagrid systems can be briefed as desirable architecture, enough flexibility, sensitive stiffness, simple compression and tension behavior, high shear mode of deflection, pleasant Ductility, and multiple structural systems.
Hexagrid system effectively spreads its mass from its center similar to a moment resisting frame [5].
Comparative Study of Seismic Behavior of Honeycomb Structure with Conventional Structure by using Staad Pro.

Several design variations of these dampers have been studied in the literature and different forms of patented hardware, the main available commercially are X-braced friction, diagonal braced friction and chevron braced friction [1], slotted bolted connection [2], Sumitomo friction [3] and Ring-type friction [4].
Okada H. and Simizu K. [7], Sato H. and Hashimoto A. [8] studied the behavior of ordinary friction type high-strength bolted joints with gap, which shows that the slip load is affected by many factors such as lap gaps.
Marsh: Response of friction damped braced frames.
Goodson, et al.: Slotted Bolted Connections in A seismic Design for Concentrically Braced Connections.
:Study on structural behavior of friction type high strength bolted joints having gap in the contact plane (part 1) Relation between bolt initial tension and slip load of the joints fastened by turn-of-nut method.

In order to enhance the damping effect various toggle brace configurations have been recently proposed.
In Fig. 1-b the corresponding force-displacement diagrams are plotted showing the typical hysteretic behavior of the damper device.
The global stiffness of the columns, supporting the mass M of the SDOF model is K, the structural damping coefficient is denoted as ( )s C .
In Table 2 the same results are reported with reference to the case in which the damper has a nonlinear behavior.
Toggle brace damper seismic energy dissipation system.

(f) A portal frame: One of the columns and the beam constitute the analytical substructure and the other column is the experimental substructure.
Overcoming the stability limit restriction of the explicit methods, the OS method is very suitable for HS of nonlinear structures with softening behavior.
The implicit integration method developed by Shing et al. [18] based on the alpha-method [15] was used in HS of concentrically braced frames [19].
There is considerably few information available about the seismic behavior of SIPs.
Vannan, Pseudodynamic tests of a concentrically braced frame using substructuring techniques, J.

Especially, columns are the most essential and important structural elements in earthquake-resistant frame structures.
To investigate the seismic behavior of reinforced concrete columns, many quasi-static cyclic loading tests have been carried out in the past, such as Watson and Park [2], Elwood and Moehle [3], and Hindi and Turechek [4].
Phase I testing, reported in this paper, consisted of benchmark tests that included characterization of the fatigue behavior of the model columns.
The maximum lateral load reached 125 kN before additional displacement caused a gradual softening of the column stiffness.
The low-cycle fatigue behavior of the reinforced concrete columns can be characterized by three stages: (1) the initial stage with the full participation of both confined core concrete and unconfined cover concrete; (2) stable behavior with deformation contributed primarily by longitudinal steel yielding and straining of confined core concrete; and (3) final failure. 2.

Timber Structures in Istanbul The Turkish timber house of diagonally braced timber frame construction with brick infill was developed in Istanbul and Edirne and was mainly erected between 15th and 18th centuries in İstanbul [3].
To achieve the stability of the frame, especially the bays beside the openings and the end bays were diagonally braced.
In order to mitigate fire spreading to upper levels, the frame was also horizontally braced forming vertical partitions.
The space between the horizontal and diagonal braces and the studs/columns were left empty and the exterior of the wall frame was sheathed with sawn timber planks.
Besides, conservation principles, material and structural behavior of historical buildings are not included in the civil engineering curricula.

The comparisons between the predicted and experimental results of column tests show that the proposed numerical analysis can reasonably describe the behaviour of reinforced concrete columns under cyclic axial compressive load with bidirectional eccentricities.
The failure behaviour and size effect rule for different seismic parameters were obtained on the basis of test results, and the size effect on the seismic performance of high-strength reinforced concrete columns with different span-to - depth ratios was confirmed.
Slender column strength is governed by many factors and requires special measures such as more reinforcement and bracing element to improve performance.
Behaviour of slender Glass Fibre Reinforced Polymer (GFRP) reinforced concrete column Ten reinforced concrete columns which consists of a rectangular cross section was used to be tested under eccentric loading.
However, the effects of the epicentre can travel through a long distance causing buildings in areas without seismic activity to suffer due to its absence of seismic design or low considerations in seismic design.

Moreover, the focus on the performance of the modular structures when assembled has predominantly centered around their behavior during seismic activities and other lateral forces [9-10].
[5] Deng E.F., Zong L., Ding Y., Luo Y.B., Seismic behavior and design of cruciform bolted module-to-module connection with various reinforcing details.
[6] Annan C.D., Youssef M.A., Naggar M.H.E., Assessment of overstrength and ductility of a four-story modular steel building braced frame (2008)
Ei Naggar, Experimental evaluation of the seismic performance of modular steel-braced frames, Engineering Structures, (2009) vol. 31, 1435–1446
Moon, Behavior of framed modular building system with double skin steel panels, Journal of Constructional Steel Research, (2011) vol. 67, 936–946