Dynamic characteristics and seismic behavior of prefabricated steel stairs in a full-scale five-story building shake table test program

The earthquake (Mw 7.3) that struck Nepal on April 25, 2015 caused damage to many civil engineering and architectural structures. While several road gabion retaining walls in mountainous regions incurred damage, there was very little information that could be used to draw up earthquake countermeasures in Nepal, because there have been few construction cases or case studies of gabion structures, nor have there been experimental or analytical studies on their earthquake resistance. Therefore, we conducted a shake table test using a full-scale gabion retaining wall to evaluate earthquake resistance. From the experiments, it was found that although gabion retaining walls display a flexible structure and deform easily due to the soil pressure of the backfill, they are resilient structures that tend to resist collapse. Yet, because retaining walls are assumed to be rigid bodies in the conventional stability computations used to design them, the characteristics of gabions as flexible structures are not taken advantage of. In this study, we propose an approach to designing gabion retaining walls by comparing the active collapse surface estimated by the trial wedge method, and the experiment results obtained from a full-scale model of a vertically-stacked wall, which is a structure employed in Nepal that is vulnerable to earthquake damage. When the base of the estimated slip line was raised for the trial wedge method, its height was found to be in rough agreement with the depth at which the gabion retaining wall deformed drastically in the experiment. Thus, we were able to demonstrate the development of a method for evaluating the seismic stability of gabion retaining walls that takes into consideration their flexibility by adjusting the base of the trial soil wedge.

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Seismic Behavior of Composite High-Rise Buildings with SRC Column, Steel Beam and RC Core Tube

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.204-208.2590 ◽

2012 ◽

Vol 204-208 ◽

pp. 2590-2594

Author(s):

Bin Zhao ◽

Juan He

Keyword(s):

Reinforced Concrete ◽

Seismic Behavior ◽

Shake Table Test ◽

Scale Model ◽

Steel Beam ◽

Shake Table ◽

Concrete Core ◽

Core Tube ◽

High Rise ◽

High Rise Building

In this research, a reduced scale model of the composite high-rise building with steel reinforced concrete column, steel beam and reinforced concrete core tube was designed and tested by using the shake table test technology. The acceleration and displacement of the model were measured during the tests. The cracking pattern and failure mechanism were illustrated. Above the shake table test, the finite element analysis of the test mode was carried out. The main effort of the numerical analysis was focused on the selection of the nonlinear models. Based on the experiment results and the strategy of considering nonlinear property of the beam-column joint and the short beam of the concrete core wall were proposed. It is proved that the proposed strategy is effective and economical for seismic behavior assessment of such composite high-rise building structure system.

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Experimental Study of Mechanical Pipe Snubber Seismic Behavior

Journal of Pressure Vessel Technology ◽

10.1115/1.2842320 ◽

1997 ◽

Vol 119 (3) ◽

pp. 384-388 ◽

Cited By ~ 4

Author(s):

D. K. Nims ◽

J. M. Kelly

Keyword(s):

Experimental Study ◽

Dynamic Characteristics ◽

Seismic Behavior ◽

Full Scale ◽

Hysteretic Behavior ◽

Scale Model ◽

Piping System ◽

Complicated Pattern ◽

Seismic Tests ◽

Input Motion

A series of seismic tests of mechanical snubbers on a full-scale model piping system provided a unique opportunity for detailed scrutiny of snubber seismic behavior on an actual piping system. The observed snubber behavior is a complicated pattern of braking and releasing, drag and drift, and the dynamic characteristics of the snubber, as well as the input motion, play a role in the response of the snubber. The snubbers were effective in limiting pipe displacements. Relative accelerations across the snubber were larger than expected. Snubber hysteretic behavior was irregular. Results from this testing are important in understanding snubber behavior, evaluating snubber performance, and in assessing alternatives to snubbers.

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