Numerical evaluations of a novel membrane element in response history analysis of reinforced concrete shear walls

The seismic response of acceleration-sensitive non-structural components in buildings has attracted the attention of a significant number of researchers over the past decade. This paper provides the results which improve the state-of-knowledge of the influences that higher vibration modes of structures and nonlinearity of non-structural components have on floor acceleration demands. In order to study these influences, a response-history analysis of a code-designed twelve-storey reinforced concrete building consisting of uncoupled ductile cantilever shear walls was conducted. The obtained absolute floor accelerations were used as a seismic input for linear elastic and nonlinear non-structural components represented by simple single-degree-of-freedom systems, and the main observations and findings related to the studied influences along the building height are presented and discussed. Additionally, the accuracy of the method for the direct determination of peak floor accelerations and floor response (acceleration) spectra recently co-developed by the first author was once again investigated and validated. A brief summary of the method is provided in the paper, along with the main steps in its application. Being relatively simple and sufficiently accurate, the method (in its simplified form) has been recently incorporated into the draft of the new generation of Eurocode 8.

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Numerical evaluations of a novel membrane element in simulations of reinforced concrete shear walls

Engineering Structures ◽

10.1016/j.engstruct.2019.109592 ◽

2019 ◽

Vol 199 ◽

pp. 109592 ◽

Cited By ~ 2

Author(s):

T.L. Chang ◽

C.-L. Lee ◽

A.J. Carr ◽

R.P. Dhakal

Keyword(s):

Reinforced Concrete ◽

Shear Walls ◽

Membrane Element

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Compression failure of thin concrete walls during 2010 Chile earthquake: lessons for Canadian design practice

Canadian Journal of Civil Engineering ◽

10.1139/cjce-2012-0315 ◽

2013 ◽

Vol 40 (8) ◽

pp. 711-721 ◽

Cited By ~ 5

Author(s):

P. Adebar

Keyword(s):

Axial Compression ◽

Shear Walls ◽

Concrete Wall ◽

Element Analysis ◽

Uniform Compression ◽

Concrete Walls ◽

Compression Strain ◽

History Analysis ◽

Chile Earthquake ◽

Response History Analysis

Numerous thin concrete walls failed in compression during the 2010 Chile earthquake. Experiments on small wall elements indicate that thin concrete walls without tied vertical reinforcement may fail very suddenly at uniform compression strains as low as 0.001 due to the thin layer of concrete between two layers of reinforcement becoming unstable. A test on a wall subjected to axial compression and strong-axis bending demonstrated that unlike a tied column, a thin concrete wall can suddenly lose all axial load-carrying capacity. Nonlinear response history analysis of a typical Chilean high-rise shear wall building indicates small global drift demands and correspondingly small curvature and compression strain demands when subjected to the ground motions measured in Santiago, which explains why most buildings were not damaged. Nonlinear finite element analysis of a typical wall step-back irregularity indicates the increase in maximum compression strains due to a reduction in wall length is much larger than predicted by a sectional analysis. Based on all the results of the current study, a number of significant changes are proposed for the 2014 edition of CSA A23.3 to avoid compression failures of thin concrete walls, including limiting the axial compression force applied to thin bearing walls, accounting for unexpected strong-axis bending of thin bearing walls, and limiting the compression strain demands on thin concrete shear walls.

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Study of the Seismic Performance of Composite Shear Walls with Embedded Steel Truss For Use in High-rise Buildings

Bauingenieur ◽

10.37544/0005-6650-2020-11-45 ◽

2020 ◽

Vol 95 (11) ◽

pp. S 12-S 21

Author(s):

Rudolf Heuer ◽

Andreas Kolbisch ◽

Ali Khazei

Keyword(s):

Shear Strength ◽

Reinforced Concrete ◽

Seismic Performance ◽

Time History ◽

Shear Walls ◽

Shear Wall ◽

Time History Analysis ◽

Braced Frames ◽

History Analysis ◽

Composite Wall

Abstract The composite wall with encased steel braces (ESB wall) is a novel type of steel–concrete composite wall that consists of a steel braced frame embedded in reinforced concrete. This arrangement is supposed to enhance the seismic performance of the wall, as the steel columns encased in the boundary elements can increase the flexural strength of the wall and the steel braces encased in the web can increase the shear strength. ESB walls have seen use in super tall building structures constructed in regions of high seismicity. The ESB walls are commonly used on stories where the shear force demand is very high. Currently, no design guidelines exist for the design of ESB Walls in the Eurocode. More research is required before a distinct set of guidelines can be prescribed for the design of ESB Walls. The present research will investigate behavior of composite walls with encased steel braces (ESB walls). Time history analysis will be performed to examine the shear strength and stiffness of the ESB walls. In this study, two frames with three floors and five floors will be modeled in ABAQUS software. Then the X- shaped braces and inverted V brace is added to frames. Later, reinforced concrete shear wall will be added to braced frames, so the steel braces encased in the reinforced concrete shear wall. Time history analysis, on the braced frames will be done Compare and note with each other. The results of the study are in good agreement with those of previous studies. However, none of these studies examined the effect of using V- and X-shaped struts and shear walls simultaneously, nor did they examine which struts reinforce the structures more strongly against earthquake vibrations. This has led the study to examine the effect of these reinforcements under various earthquakes. In future studies, reinforced concrete structures can also be used in addition to steel structures, and the results can be compared. In addition, these braces can also be used in other parts of the building. To meet this objective, one can use the very important data provided in this thesis, and ultimately better and more accurate results can be extracted using this approach. The main aim of this thesis is to study the effect of increasing the number of floors on how to extend the stress on the building structure. To this end, the number of floors increased from three to five. Therefore, it can be concluded that an increase in the number of floors also more than 5 storey causes stress values, but these modes are quite consistent with the three- and five-storey buildings.

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The energy dissipation effects of redundant members in silos under earthquakes

Bulletin of the New Zealand Society for Earthquake Engineering ◽

10.5459/bnzsee.20.4.269-274 ◽

1987 ◽

Vol 20 (4) ◽

pp. 269-274

Author(s):

Zhiming Li ◽

Shujiang Geng

Keyword(s):

Reinforced Concrete ◽

Energy Dissipation ◽

Structural Model ◽

Structural Parameters ◽

Lateral Force ◽

Strong Base ◽

History Analysis ◽

Response History Analysis ◽

Application Potential ◽

Internal Forces

An analytical study is made of the response to strong base motion of reinforced concrete silo structures having energy dissipation redundant members. The structural model consists of an axisymmetric silo body supported by reinforced concrete columns. Analytical methods used include inelastic dynamic response history analysis, inelastic static analysis, and elastic modal spectral analysis (Building Code of China). The sensitivity of the structural parameters, such as the location of redundant members, relative linear stiffness, and reinforcement ratios, are examined for lateral force and ground motions. Based on the data presented, it is concluded that the advantages of energy dissipation redundant members are of ensuring yielding hinges occur in selected elements, improving the distribution of internal forces, and providing increased ductility. Numerical examples are discussed to show the application potential.

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Effect of configuration of shear walls at story plan to seismic behavior of high-rise reinforced concrete buildings

Challenge Journal of Structural Mechanics ◽

10.20528/cjsmec.2020.01.004 ◽

2020 ◽

Vol 6 (1) ◽

pp. 31

Author(s):

Mustafa Tolga Çöğürcü ◽

Mehmet Uzun

Keyword(s):

Reinforced Concrete ◽

Time History ◽

Shear Walls ◽

Horizontal Displacement ◽

Shear Wall ◽

Building Model ◽

High Rise ◽

History Analysis ◽

Earthquake Load ◽

Load Mode

In developing countries, the need for shelter, working area, shopping and entertainment centers is increasing due to the increasing population effect. In order to meet this need, it is necessary to turn to high-rise buildings. Significant damages have been observed as a result of insufficient horizontal displacement stiffness of high-rise buildings in major earthquakes in previous years. It is known that as the height of the structure increases, the displacement demand of the structure also increases. Since it is accepted that the structure will make inelastic deformation in the design of the structure, these displacements increase to very high levels as the number of stories increases. For this reason, damages can be much higher than expected. In order to limit the level of damage that may occur in high-rise buildings, the horizontal displacement of buildings is limited in many regulations in our age. This limitation is possible by increasing the rigidity of the structures against horizontal displacement. In recent years, the use of shear wall has increased due to the horizontal displacement limitation in the regulations. The use of shear walls in buildings limits the horizontal displacement. However, the choice of where the shear walls will be placed on the plan is very important. Failure to place the shear walls correctly may result in additional loads in the structure. It can also lead to torsional irregularity. In this study, a 10-storey reinforced concrete building model was created. Shear wall at the rate of 1% of the plan area of the building was used in the building. The shear walls are arranged in different geometric shapes and different layouts. The earthquake analysis of 5 different models were performed. Equivalent Earthquake Load, Mode Superposition and Time History Analysis methods were used for earthquake analysis. The results were compared and a proposal was made for the geometry and configuration of the shear wall.

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