scholarly journals Slenderness Ratio and Influencing Parameters on the NL Behaviour of RC Shear Wall

2021 ◽  
Vol 7 (12) ◽  
pp. 2043-2067
Author(s):  
A. Atmani ◽  
Z. Boudaoud ◽  
N. Djebbar
Keyword(s):  
Structural Damage ◽  
Slenderness Ratio ◽  
Pushover Analysis ◽  
Shear Walls ◽  
Reinforcement Ratio ◽  
Structural Elements ◽  
Concrete Compressive Strength ◽  
Flexural Behaviour ◽  
Zone Depth ◽  
Rc Shear Wall

Shear walls are very efficient structural elements to resist lateral seismic disturbance. Despite the aforementioned seismic performance, recent investigations report that they have suffered from significant structural damage after recent seismic activity, even for those complying with seismic provisions. These deficiencies in resistance and deformation capacities need to be explored. This study considers the influence of plastic length Lp, concrete compressive strength f_c28, longitudinal reinforcement ratio ρl, transverse reinforcement ratio ρsh, reduced axial load ν, confinement zone depth CS and focusing on the geometric slenderness λ. The parametric study has been conducted through NL pushover analysis using Peform3D software. The chosen coupled shear-flexure fiber macro model was calibrated with well-known cyclic experimental specimens. The paper points out the discrepancy between the two well-known codes EC8 and ASCE/SEI 41-13. In fact, the value of the slenderness ratio (λ) that trigger the beginning of a purely flexural behaviour recommended by EC8 (λ>2) is very different from the value of the ASCE/SEI 41-13 (λ>3) without accounting for the effect of the reduced axial force. Finally, it was found that RCW capacities are very sensitive to f_c28, ν, ρl, Lp and less sensitive to ρsh and CS. However, (λ) is the most decisive factor affecting the NL wall response. A new limit of slenderness and appropriate deformations of rotations are recommended to provide an immediate help to designers and an assistance to those involved with drafting codes. Doi: 10.28991/cej-2021-03091777 Full Text: PDF

The Influence of Structural Damage on the Vibration Characteristics of Shear-Wall Buildings

2012 ◽  
Vol 193-194 ◽  
pp. 1216-1220 ◽  
Author(s):  
Kai Huang ◽  
Li Hua Zou ◽  
Jian Mei Chen
Keyword(s):  
Plastic Zone ◽  
Structural Damage ◽  
Pushover Analysis ◽  
Shear Walls ◽  
Shear Wall ◽  
Internal Force ◽  
Vibration Characteristics ◽  
Wall Structure ◽  
Wall Structures ◽  
The Continuum

To understand the higher modal effect on the accuracy of pushover analysis for shear wall structure, the influence of damage on the vibration characteristics of shear-wall structures is investigated. Employing the continuum technique, the shift of modal shapes and periods for the first three modes is obtained when the plastic zone exists in the bottom of the shear wall. It can be conclude that plastic zone may enhance the higher modal effect when the internal force responses of shear walls are considered. The higher modal contribution can not be neglected when computing the nonlinear earthquake responses of shear wall structures.

scholarly journals The impact of shear wall location on the seismic response of RC frame buildings resting on sloping ground

2019 ◽  
Vol 2 (1) ◽  
pp. 61-68
Author(s):  
Upama Acharya ◽  
Jagat Kumar Shrestha
Keyword(s):  
Response Spectrum ◽  
Pushover Analysis ◽  
Structural Response ◽  
Earth Pressure ◽  
Shear Walls ◽  
Shear Wall ◽  
Sloping Ground ◽  
Negative Effect ◽  
Rc Shear Wall ◽  
The Impact

It is observed during the past earthquakes, buildings in hilly regions have experienced high degree of damage leading to collapse though they have been designed for safety of the occupants against natural hazards. Hence, while adopting practice of multistory buildings in these hilly and seismically active areas, utmost care should be taken for making these buildings earthquake resistant. For the buildings on sloping ground, the height of columns below plinth level is not same which affects the performance of building during earthquake. Hence to improve the seismic performance of building shear walls play very important role.It is very necessary to determine the most effective location of shear walls. Shear wall arrangement must be accurate, because if not, it will cause negative effect instead. This paper is aimed at predicting the effect of positioning RC shear wall of different shape on the structural response of RC building resting on sloping ground. Eight models have been prepared considering earth pressure and without considering earth pressure. The displacement of building is to be determined by nonlinear static pushover analysis. For the purpose of pushover analysis and response spectrum analysis finite element-based software SAP 2000 has been utilized.

Influence of the distribution of the shear walls on the seismic response of the buildings

2020 ◽  
Vol 15 (1) ◽  
pp. 37-44
Author(s):  
El Mehdi Echebba ◽  
Hasnae Boubel ◽  
Oumnia Elmrabet ◽  
Mohamed Rougui
Keyword(s):  
Structural Analysis ◽  
Seismic Response ◽  
Natural Frequency ◽  
Structural Design ◽  
Structural Response ◽  
Shear Walls ◽  
Structural Elements ◽  
Analysis Software ◽  
Ansys Apdl ◽  
The Impact

Abstract In this paper, an evaluation was tried for the impact of structural design on structural response. Several situations are foreseen as the possibilities of changing the distribution of the structural elements (sails, columns, etc.), the width of the structure and the number of floors indicates the adapted type of bracing for a given structure by referring only to its Geometric dimensions. This was done by studying the effect of the technical design of the building on the natural frequency of the structure with the study of the influence of the distribution of the structural elements on the seismic response of the building, taking into account of the requirements of the Moroccan earthquake regulations 2000/2011 and using the ANSYS APDL and Robot Structural Analysis software.

scholarly journals EFFECT OF GAMMA IRRADIATION ON THE DESOXYRIBONUCLEASE II ACTIVITY OF ISOLATED MITOCHONDRIA

1957 ◽  
Vol 3 (2) ◽  
pp. 239-248 ◽  
Author(s):  
Shigefumi Okada ◽  
Lee D. Peachey
Keyword(s):  
Structural Damage ◽  
Liver Homogenate ◽  
Liver Mitochondria ◽  
Structural Elements ◽  
Dnase Ii ◽  
Mitochondrial Structure ◽  
Co60 Source ◽  
Mitochondrial Suspension ◽  
High Doses ◽  
Isolated Liver

1. Exposure of isolated liver mitochondria to high doses of gamma rays from a Co60 source causes the level of DNase II activity to increase. Treatment of the mitochondria with sonic vibration causes a further elevation of the activity to a level which is independent of the prior radiation dose. 2. Such increased mitochondrial DNase II activity appears to be due to the "structural damage" of the subcellular particulates caused by the ionizing radiation. Other methods of disrupting the mitochondrial structure also cause increased DNase II activity. A causal relationship between the structural alteration and the increased enzymatic activity is postulated. 3. The DNase II activity appears to be closely associated with the structural elements of the mitochondria and remains associated with the fragments after irradiation. 4. Upon irradiation, the mitochondrial suspension releases ultraviolet-absorbing materials which are probably nucleotide in nature. 5. The possibility of localization of DNase activity in the lysosome fraction of de Duve (15) is discussed. It is felt that DNase II is at least in part a mitochondrial enzyme and that probably the conclusions drawn here would be applicable to any DNase II present in the lysosomes as well. 6. Irradiation of whole liver homogenate causes no increased DNase II activity. The experiments do not provide any information on the presence or action of protective substances in the homogenate.

Pushover Analysis Based on Equivalent Diagonal Springs for the Assessment of the Seismic Safety of Post-and-Beam Timber Buildings Braced with Nailed Shear Walls

2017 ◽  
Vol 755 ◽  
pp. 170-180
Author(s):  
Natalino Gattesco ◽  
Ingrid Boem
Keyword(s):  
Static Analysis ◽  
Pushover Analysis ◽  
Shear Walls ◽  
Nonlinear Static Analysis ◽  
Plastic Behavior ◽  
Ground Acceleration ◽  
Good Reliability ◽  
Equivalent Viscous Damping ◽  
Seismic Safety ◽  
Capacity Spectrum

A method for a simplified modeling of post-and-beam timber buildings braced with nailed shear walls, useful for seismic design purposes, is presented and discussed in the paper. This strategy is based on the schematization of the vertical diaphragms through equivalent diagonal springs with elastic-plastic behavior and allows the assessment of the resisting ground acceleration by performing nonlinear static analysis; the Capacity Spectrum method based on equivalent viscous damping was applied. This nonlinear procedure constitutes a reliable and simple alternative to the linear static analysis using the behavior factor q. The procedures to determine the characteristics of the equivalent elements (stiffness and load-carrying capacity) are based on analytical evaluations, starting from the actual characteristic of shear walls. A comparison between the results of numerical simulation based of more refined and complex models, previously presented by the authors, and this time-reducing, simplified analysis proved the good reliability of the method.

scholarly journals Analisis Pengaruh Lokasi Dinding Geser Terhadap Pergeseran Lateral Bangunan Bertingkat Beton Bertulang 5 Lantai

2021 ◽  
Vol 4 (1) ◽  
pp. 16
Author(s):  
Leonardus Setia Budi Wibowo ◽  
Dermawan Zebua
Keyword(s):  
Lateral Displacement ◽  
Shear Walls ◽  
Seismic Loading ◽  
Shear Wall ◽  
Structural System ◽  
Earthquake Force ◽  
Earthquake Resistant ◽  
Story Drift ◽  
Frame System ◽  
Rc Shear Wall

Indonesia is one of the countries in the earthquake region. Therefore, it is necessary to build earthquake-resistant buildings to reduce the risk of material and life losses. Reinforced Concrete (RC) shear walls is one of effective structure element to resist earthquake forces. Applying RC shear wall can effectively reduce the displacement and story-drift of the structure. This research aims to study the effect of shear wall location in symmetric medium-rise building due to seismic loading. The symmetric medium rise-building is analyzed for earthquake force by considering two types of structural system. i.e. Frame system and Dual system. First model is open frame structural system and other three models are dual type structural system. The frame with shear walls at core and centrally placed at exterior frames showed significant reduction more than 80% lateral displacement at the top of structure.

scholarly journals Evaluasi Struktur Bangunan Pasar Inpress Blok IV Gedung B dengan Metode Pushover

CIVED ◽  
2021 ◽  
Vol 8 (3) ◽  
pp. 117
Author(s):  
Lisyana Junelin Restu ◽  
Eka Juliafad ◽  
Fajri Yusmar
Keyword(s):  
Pushover Analysis ◽  
Performance Level ◽  
Structural Performance ◽  
Risk Category ◽  
Structural Elements ◽  
Analysis Method ◽  
Earthquake Loads ◽  
Tsunami Risk ◽  
Vertical Evacuation ◽  
Immediate Occupancy

AbstractInpres market block IV Pasar Raya Padang is not designed as a shelter building, but is designated as a vertical evacuation site when a tsunami occurs. This study aims to evaluate the structural performance of Inpress market block IV zone B. The method used for this research is the pushover analysis method. According to FEMA P-646/2019, vertical evacuation refuge structures are included in tsunami risk category IV, based on the risk category the maximum performance level is at the Immediate Occupancy (IO). For loads on buildings, refer to SNI 1727:2020 and SNI 1726:2019 for earthquake loads. For the calculation of the capacity of concrete structural elements, refer to SNI 2847:2019. Structural analysis was carried out using the SAP2000 version 16. After analysis, based on performance points, drift ratio that occur due to earthquake loading in X-direction and Y-direction are 0,05875% and 0,0067%. The maximum total drift that occurs is smaller than that required by ATC-40 for the Immediate Occupancy performance level, which is 1%. Thus, the structure performance level is Immediate Occupancy. This means that the Inpress market block IV building is still strong enough against earthquake loads.

Steel Fibre Performance in Concrete with Expansive Additives under Restrained Hardening Conditions

2018 ◽  
Vol 788 ◽  
pp. 30-35
Author(s):  
Arturs Lukasenoks ◽  
Rolands Cepuritis
Keyword(s):  
Compressive Strength ◽  
Steel Fibre ◽  
Single Fibre ◽  
Steel Shell ◽  
Concrete Compressive Strength ◽  
Flexural Behaviour ◽  
Pull Out ◽  
Delamination Resistance ◽  
Expansive Additive ◽  
Standard Steel

Steel moulds in the form of a rigid cubical shell were developed in order to investigate single steel fibre pull-out resistance in concrete with expansive additive under restrained hardening conditions. The cubical shell (100 x 100 x 100 mm) with wall thickness of 5 mm was designed with two openings – a small 4 mm hole for fibre embedment in concrete and a larger opening for filling the concrete. Standard beam (100 x 100 x 400 mm) and cube (150 x 150 x 150 mm) samples were also manufactured and hardened under and without restrained conditions, where the restraint was realised by rigid standard steel moulds. All the restrained conditions realized by either the developed cubical steel shell (for single fibre pull-out) or existing beam and cube moulds simulate internal (from steel fibres in concrete) and external (from friction against sub-base) restraints that hinder expansion of the concrete due to the use of special expansive additives in a flooring slab structure installed on ground. Samples with a single hooked-end steel fibre (50 mm long and 0.75 mm in diameter), with and without expansive additive were manufactured and tested in the developed mould geometry. The results show that restrained expansion in concrete with expansive additives positively affects concrete compressive strength, single fibre pull-out and flexural behaviour. Concrete compressive strength increases by 7.5 %, single fibre delamination resistance increases by 24 %, the peak pull-out load by 10.8 % while the flexural strength increases by 3.1 %.

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