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Article
Publication date: 13 June 2016

Khalid Abou El-Ftooh, Ahmed Atta, Ayman Ahmed Seleemah and Salah El-Din Fahmy Taher

Separately, nonlinear finite element analysis, artificial neural networks (ANNs) and continuous damage mechanics (CDM) attracted many investigators to model masonry infilled frames

Abstract

Purpose

Separately, nonlinear finite element analysis, artificial neural networks (ANNs) and continuous damage mechanics (CDM) attracted many investigators to model masonry infilled frames. The purpose of this paper is to pursue four phases to develop a versatile model for partially and fully low-rise infilled RC frames using these tools.

Design/methodology/approach

The first phase included the study of the behavior of 1,620 low-rise infilled reinforced concrete frames using macro-scale nonlinear pushover finite element analysis. The approach helped to explore the effects of imposing different masonry infill distributions for one of the typical models of school buildings in Egypt. The outputs of this phase were used in the second phase for the development of an ANN model where input neurons included number of stories, continuity conditions, frame geometry, infill distribution and properties of RC sections. The third phase included the employment of the notions of CDM on the structural scale. Monitoring frames’ stiffness degradation allowed for damage variables identification. In the fourth phase, the simpler equivalent static lateral load (ESLL) for elastic analysis was employed in conjunction with ANN and CDM to obtain the capacity curves for partially and fully low-rise infilled RC frames.

Findings

The obtained capacity curves were compared with the nonlinear finite element results. The close agreement of all curves indicated how rigorous, yet simple, the suggested solution procedure is.

Social implications

The study is concerned with an important type of service buildings. These are the school buildings of Egypt.

Originality/value

The paper presents a combination of four phases that include FE analysis, ANNs, ESLL, and CDM to obtain the capacity curves for partially and fully low-rise infilled RC frames. Such a combination of approaches in tackling a practical problem related to service buildings is innovative and deserves research interest.

Article
Publication date: 7 July 2017

Puneet Kumar and Gaurav Srivastava

Reinforced concrete structural frames with masonry infills (infill-frames) are commonly used for construction worldwide. While the behavior of such frames has been studied…

Abstract

Purpose

Reinforced concrete structural frames with masonry infills (infill-frames) are commonly used for construction worldwide. While the behavior of such frames has been studied extensively in the context of earthquake loading, studies related to their fire performance are limited. Therefore, this study aims to characterize the behavior of infill-frames under fire exposure by presenting a state-of-the-art literature review of the same.

Design/methodology/approach

Both experimental and computational studies have been included with a special emphasis on numerical modeling (simplified as well as advanced). The cold behavior of the infill-frame and its design requirements in case of fire exposure are first reviewed to set the context. Subsequently, the applicability of numerical modeling strategies developed for modeling cold infill-frames to simulate their behavior under fire is critically examined.

Findings

The major hurdles in developing generic numerical models for analyzing thermo-mechanical behavior of infill-frames are identified as: lack of temperature-dependent material properties, scarcity of experimental studies for validation and idealizations in coupling between thermal and structural analysis.

Originality value

This study presents one of the most popular research problems connected with practical and reliable utilization of numerical models, as a good alternative to expensive traditional furnace testing, in assessing fire resistance of infill-frames. It highlights major challenges in thermo-mechanical modeling of infill-frames and critically reviews the available approaches for modeling infill-frames subjected to fire.

Details

Journal of Structural Fire Engineering, vol. 8 no. 3
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 8 October 2019

Bing Bing Tu

A large number of earthquake damages showed that infill walls have obvious influence on the seismic damage performance of RC frame structures. The purpose of this paper is to…

Abstract

Purpose

A large number of earthquake damages showed that infill walls have obvious influence on the seismic damage performance of RC frame structures. The purpose of this paper is to study the effect of infill walls on the cumulative plastic deformation energy of RC frame structures, for which four RC frame structures are build and the time-history response analysis under unidirectional seismic action is presented.

Design/methodology/approach

The time-history response analysis under unidirectional seismic action is presented. Then the effect of periodic reduction coefficient on the cumulative plastic deformation energy of the structures, the beams and the columns is investigated.

Findings

Finally, the quantitative calculation formulas are provided. The results show that the periodic reduction coefficient has an obvious effect on the distribution of the accumulated plastic deformation energy, and the influence rules are presented here.

Originality/value

The effect of infill walls on the cumulative plastic deformation energy of RC frame structures is quantitatively analyzed here.

Details

Multidiscipline Modeling in Materials and Structures, vol. 16 no. 2
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 13 June 2016

João Dias-Oliveira, H Rodrigues and Humberto Varum

When a numerous amount of buildings was built in reinforced concrete, in a period when the regulations did not have the design philosophy for the occurrence of earthquakes, it is…

Abstract

Purpose

When a numerous amount of buildings was built in reinforced concrete, in a period when the regulations did not have the design philosophy for the occurrence of earthquakes, it is of extreme importance to carry out full and effective structural assessments, specially considering and comparing bare frame and infilled structure. The paper aims to discuss these issues.

Design/methodology/approach

Among several possibilities to make the evaluation as, simplified, linear analysis and static non-linear analysis, the non-linear dynamic can provide the most accurate numerical behaviour compared to the real one. The time-history non-linear analyses are developed on the software SeismoStruct for different levels of intensity. Local verifications are then applied separately from both Eurocode and Italian Code.

Findings

The application of validated models for the analysis of real buildings allows a complete seismic assessment. The level of uncertainty increases integrating particularities regarding the infill masonry walls. The paper shows important global and local seismic safety for these complex typology of buildings.

Originality/value

A representative common concrete structure without seismic provisions is first analysed and discussed in terms of global behaviour, deformations and progression of forces. The case study structure is considered both as bare structure and with integrated infill panels. It is also discussed in a local level, about brittle and ductile mechanisms, and extra comparisons between different interpretations of different standards. The case study structure is considered both as bare structure and with integrated infill panels.

Details

Engineering Computations, vol. 33 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 9 December 2020

Parthasarathi N. and Satyanarayanan K.S.

Technological innovations in the construction field correspond to a wider revolution in metropolitan life and in structural design. With the demand for advanced concrete…

Abstract

Purpose

Technological innovations in the construction field correspond to a wider revolution in metropolitan life and in structural design. With the demand for advanced concrete technology, the introduction of new reinforced materials in concrete, namely, iron, steel and other reinforcing elements. Reinforcement in concrete is developed in the centuries back and several advancements are being stirred to improvise the properties of the concrete through reinforcements. On the basis of this finding from the earlier research studies, a reinforcement methodology is practiced on the current study to investigate the deflection of the M30 mix concrete frame under thermal load conditions.

Design/methodology/approach

For the examination, corner and the middle frame are considered with the reinforcement provided on four zones with 16-mm diameter for compression and 8-mm diameter is used for the stirrup at 150 mm c/c spacing. The load is applied to the column with live and wall load of 3.5 kN/m and 14.7KN/m. The experimentation is carried out by the finite element analysis strategy in ABAQUS simulation software with five test conditions with the bare frame at single, two and three-bay infill. The model of the frame is developed and meshed with the meshing type of C3D8T under 8-node thermally coupled brick mesh type for the mesh size of 25 mm.

Findings

From the simulation outcome, the effect of thermal gradient on the reinforced concrete is analyzed and its structural properties are plotted as performance graphs in the result section.

Originality/value

Under the thermal load condition, the model is simulated for 180 min for five different cases and analyzed the deflection parameters such as deformation, stress and failure rate.

Details

Journal of Structural Fire Engineering, vol. 12 no. 1
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 1 March 2002

Hamdy Mohy Afefy, Salah El‐Din Fahmy Taher, Abdel‐Hakim A. Khalil and Mohamed E. Issa

The most simple equivalent frame system with reduced degrees of freedom is proposed for handling multi‐story multi‐bay infilled frames. The system is composed of homogenized…

Abstract

The most simple equivalent frame system with reduced degrees of freedom is proposed for handling multi‐story multi‐bay infilled frames. The system is composed of homogenized continuum for the reinforced concrete members braced with unilateral diagonal struts for each bay, which are only activated in compression. Identification of the equivalent system characteristics and nonlinear material properties are accomplished from the concepts of inverse analysis approach along with statistical tests of hypotheses is employed to establish the appropriate filtering scheme and the proper accuracy tolerance. The suggested system allows for nonlinear finite element static and dynamic analysis of sophisticated infilled reinforced concrete frames. Sensitivity analysis is undertaken to check the suitability of the proposed system to manipulate various structural applications.

Details

Engineering Computations, vol. 19 no. 2
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 11 February 2019

Mahnaz Kheradmand, Katayoun Jahangiri, Sanaz Sohrabizadeh, Hamid Safarpour and Reza Khani Jazani

The purpose of this paper is to identify the vulnerable factors in the neighborhood and vulnerability assessment of residential, medical center, school buildings, the road…

Abstract

Purpose

The purpose of this paper is to identify the vulnerable factors in the neighborhood and vulnerability assessment of residential, medical center, school buildings, the road networks and the green spaces as vital and critical land uses to get general estimation of the situation for risk reduction planning.

Design/methodology/approach

Seismic vulnerability assessment of buildings was performed using the rapid visual screening data collection form of FEMA P 154 (2015). The assessment of the road was carried out using an empirical model, and the condition of the green spaces was assessed complying with standards using GIS.

Findings

The results of research indicated that about 37 percent of selected residential buildings, 81.08 percent of schools and two health care centers are likely to be vulnerable to earthquake.

Originality/value

Based on the results of this study, many of the structures should be further evaluated. Strengthening of poor-resistant elements of the roads is recommended and must be in order. Although the green spaces are well distributed in the neighborhood, they are ill-equipped of necessary facilities and their development is also recommended.

Details

International Journal of Structural Integrity, vol. 10 no. 2
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 11 June 2018

Patricia Raposo, André Furtado, António Arêde, Humberto Varum and Hugo Rodrigues

The infill masonry walls in recent worldwide earthquakes have shown that it is necessary to conduct further studies to characterize the behavior of existing buildings and, in…

Abstract

Purpose

The infill masonry walls in recent worldwide earthquakes have shown that it is necessary to conduct further studies to characterize the behavior of existing buildings and, in particular, of infill masonry walls under seismic activity. The lack of characterization studies of infill walls made by concrete blocks justifies the investigation reported herein, which includes experimental tests on sample sets to evaluate the mechanical properties of masonry components (units and mortar) and assemblages (wallets) made with masonry units from Faial. For the later, normal compressive, diagonal tensile/shear and out-of-plane flexural strengths were obtained according to standard procedures, the results of which are presented in the manuscript. The paper aims to discuss these issues.

Design/methodology/approach

One experimental campaign was conducted with the aim to mechanically characterize concrete blocks masonry samples. Several experimental tests were carried out in full-scale masonry concrete wallets according to the constructive methodology used.

Findings

Based on the data obtained from the mechanical characterization tests of the concrete masonry blocks, it can be seen that under simple compression, the masonry specimens’ average resistance is about 6 times superior than the average resistance to diagonal shear/tension, while the stiffness is almost doubled. In simple compression tests, it was observed that the masonry specimens cracked in areas of higher drilling of the blocks. In the tensile tests by diagonal compression, it was found that the test specimens were mainly fissured by the block/mortar joint interfaces, following the delineation of settlement and top joints.

Originality/value

There are no experimental results available in the literature for this type of bricks that can contribute to the development of numerical studies.

Details

International Journal of Structural Integrity, vol. 9 no. 3
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 28 May 2020

Ching-Shan Chen

Taiwan experiences frequent seismic activity. Major earthquakes in recent history have seriously damaged the school buildings. School buildings in Taiwan are intended to serve…

Abstract

Purpose

Taiwan experiences frequent seismic activity. Major earthquakes in recent history have seriously damaged the school buildings. School buildings in Taiwan are intended to serve both as places of education and as temporary shelters in the aftermath of major earthquakes. Therefore, the seismic performance assessments of school buildings are critical issues that deserve investigation.

Design/methodology/approach

This paper develops a methodology that uses principal component analysis to generalize the seismic factors from the basic seismic parameters of school buildings, uses data mining to cluster different school building sizes and uses grey theory to analyze the relationship between seismic factors and the seismic performance of school buildings. Additionally, this paper employs the Artificial Neural Network (ANN) to deduce the seismic assessment model for school buildings. Finally, it adopts support vector machine to validate the ANN’s deductive results.

Findings

An empirical study was conducted on 326 school buildings in the central area of Taichung City, Taiwan, to illustrate the effectiveness of the proposed approach. Results show that thickness of wall and width of middle-row column relate significantly with school-building seismic performance.

Originality/value

This paper provides a model that structural engineers or architects may use to design school buildings that are adequately resistant to earthquakes as well as a reference for future academic research.

Details

Engineering Computations, vol. 37 no. 9
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 26 June 2019

Guiyun Xia, Wenya Shu and Ilinca Stanciulescu

This paper aims to propose an efficient method to conduct the preliminary analyses of medium or high-rise wall-frame structural systems with vertically varying properties. To this…

Abstract

Purpose

This paper aims to propose an efficient method to conduct the preliminary analyses of medium or high-rise wall-frame structural systems with vertically varying properties. To this end, a finite element is formulated to take the shear deformation of the shear wall and the constrained moment of the link beam.

Design/methodology/approach

The differential equation of the structure is derived from the total potential energy. Its homogenous solutions are functions of initial parameters (deflections and inner forces). To solve the structure with vertically non-uniform properties, the authors first use the classical Timoshenko beam element and then heuristically propose a finite element that uses the initial parameter solutions as shape functions and is easier to implement. A post-processing method to compute the shear force in the frame and shear wall is developed. Modal analysis using the consistent mass matrix is also incorporated. Numerical examples demonstrate the accuracy and mesh independency of the proposed element.

Findings

The shear deformation of the shear wall and the constrained moment of the link beam significantly influence the static response of the structure. Taking into account the shear deformation can eliminate the misleading result of zero-base shear force of the frame and give much better predictions of the system natural frequencies.

Originality/value

The proposed method achieves higher accuracy than the classical approach most often used. The finite element formulation derived from transformations of the initial parameter solutions is simple and has superior numerical performance. The post-processing method allows for a fast determination of the shear force distributions in the shear wall and frame.

Details

Engineering Computations, vol. 36 no. 6
Type: Research Article
ISSN: 0264-4401

Keywords

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