Papers by Sherif Ahmed Mourad
Heritage buildings embody cultural identity and contribute significantly to economy and social we... more Heritage buildings embody cultural identity and contribute significantly to economy and social well-being. However, many are severely deteriorated due to aging, neglect, and absence of effective management systems. Restoration decision-making is complex given the large number of structures in need for intervention, high restoration costs, limited funding, and the challenge of prioritizing interventions considering each building's unique architectural, social, and economic value. This research, therefore, proposes a novel comprehensive computer-aided Decision Support System (DSS), inspired by infrastructure asset management system (IAMS), to optimize fundallocation among heritage buildings under budget constraints. The DSS assesses the structures' condition, vulnerability, uncertain deterioration behaviour, and intervention costs, alongside its unique value and expected socioeconomic benefit using multi-criteria decision-making methods. These inputs feed into mathematical optimization models that maximize structural performance and socioeconomic benefit over a defined funding period. To facilitate use by stakeholders, a userfriendly interface was developed. The system was applied to 39 severely deteriorated buildings in Historic Cairo, a UNESCO World Heritage Site, and was validated through discussions with key policymakers, confirming its practical value. In essence, this research offers a robust, data-driven tool for strategic restoration planning and sustainable heritage preservation.
Journal of Engineering and Applied Science, Sep 8, 2021
In this study, numerical models were developed to predict the behavior of steel extended end-plat... more In this study, numerical models were developed to predict the behavior of steel extended end-plate moment connections subjected to static and blast-like loading. Two types of extended end-plate connections were considered, stiffened, and unstiffened, with pretensioned bolts. The models were verified by comparing the results with published experimental data. The models were used to compute the moment-rotation curves for the connection under static loading, and then under different blast durations. The pressure impulse diagram and the energy dissipation for the connection under dynamic loading were determined. The failure modes were examined, and the numerical results were compared with the simplified models presented in codes and standards. Improvement in the performance of the connection by adding one or two stiffeners was demonstrated. For the configuration studied, introducing a stiffener increased plastic dissipation energy for blast loading by 45% compared to the unstiffened connection, whereas under static loading, the plastic energy dissipation for stiffened connection, SC2, was higher than the unstiffened connection by 30%. A conservative estimate for the dynamic increase factor (DIF) was found to be 1.2 for steel yield stress and 1.05 for bolt failure.
An experimental study was performed to investigate the ultimate strength and modes of failure of ... more An experimental study was performed to investigate the ultimate strength and modes of failure of axially loaded channel rack columns with rear flanges. A total of 16 column specimens fabricated by press-brake forming method were tested up to failure. The material properties of the column specimens were determined using standard tensile coupon tests. The deformation and stress behavior of the tested columns were monitored using displacement transducers and strain gauges. The effects of column slenderness ratio, thickness, perforation, and end conditions on the column ultimate strength and mode of failure were studied. The test failure loads were compared to the ultimate load predictions of the 2001 AISI North American Specification. The comparison showed that the AISI procedure overestimates the failure load, which suggests that the proportioning of the cross-sectional dimensions of the lipped channel sections with rear flanges has a direct effect on the capacity of the columns.
SN applied sciences, Oct 20, 2022
This work intends to provide seismic vulnerability analysis for a building stock in Al Khalifa Di... more This work intends to provide seismic vulnerability analysis for a building stock in Al Khalifa District, Fatimid Cairo while focusing on the historic buildings in the area. The work represents part of an interdisciplinary study targeting the management and conservation of a UNESCO World Heritage Site. The project inspects several aspects including behavior of masonry walls, structural health monitoring of selected structures, conservation studies, in addition to influence of rising ground water. In the current study, seismicity of Egypt generally and Cairo specifically is reviewed. Afterwards, large-scale seismic vulnerability is adopted to calculate the vulnerability index for buildings within the study area. Data are collected through extensive on-site surveys for more than one hundred buildings. Observed typologies are listed alongside possible mechanisms of failure. Egypt has moderate seismic hazard; however, many buildings are prone to damage due to inadequate seismic design. This leads to retrofitting requirements to reduce seismic vulnerability and adhere to imposed seismic requirements in design codes. The study is intended to understand seismic risk of buildings within study area as part of a comprehensive study. Developed vulnerability map show that many buildings are prone to damage during seismic events.
International Journal of Advances in Structural and Geotechnical Engineering
Egypt is one of the richest countries in its historic and tourism attractions which are among the... more Egypt is one of the richest countries in its historic and tourism attractions which are among the main contributors to the country's gross domestic product (GDP). Historic Cairo which has hundreds of mesmerizing historic Coptic and Islamic structures (mosques, churches, mausoleums, etc.) has been identified by UNESCO as a world heritage site since 1979. However, it has been noticed that its share in the tourism revenues is quite low compared to its value. One of the reasons is that many of the historic structures are closed because they are severely deteriorated due to urban expansion, pollution, environmental hazards, and aging. To revive the tourism in Historic Cairo, the government has been directing its efforts towards the conservation of those structures and reopening them to the public, and thus increase tourism-based revenues. However, the funding needed to restore all structures is very limited. There are hundreds of historic structures in need for restoration with a budget of more than one billion EGP. Accordingly, this research proposes a decision support system inspired by infrastructure asset management system (IAMS) to guide the fund allocation process. It follows the sequential steps of IAMS from asset inventory, condition assessment, up to prioritization and fund-allocation, yet considering the unique value of each heritage building and the expected socioeconomic benefits of restoring the structures and upgrading their surrounding areas. Therefore, this new structured decision support system will help policy makers develop the best rational restoration plan that will help rejuvenate Historic Cairo, and subsequently Egypt's tourism revenues.
Journal of Engineering and Applied Science, Sep 8, 2021
In this study, numerical models were developed to predict the behavior of steel extended end-plat... more In this study, numerical models were developed to predict the behavior of steel extended end-plate moment connections subjected to static and blast-like loading. Two types of extended end-plate connections were considered, stiffened, and unstiffened, with pretensioned bolts. The models were verified by comparing the results with published experimental data. The models were used to compute the moment-rotation curves for the connection under static loading, and then under different blast durations. The pressure impulse diagram and the energy dissipation for the connection under dynamic loading were determined. The failure modes were examined, and the numerical results were compared with the simplified models presented in codes and standards. Improvement in the performance of the connection by adding one or two stiffeners was demonstrated. For the configuration studied, introducing a stiffener increased plastic dissipation energy for blast loading by 45% compared to the unstiffened connection, whereas under static loading, the plastic energy dissipation for stiffened connection, SC2, was higher than the unstiffened connection by 30%. A conservative estimate for the dynamic increase factor (DIF) was found to be 1.2 for steel yield stress and 1.05 for bolt failure.
Buildings
Historic Cairo has been a UNESCO World Heritage Site since 1979. It has more than 600 historic st... more Historic Cairo has been a UNESCO World Heritage Site since 1979. It has more than 600 historic structures, which require extensive studies to sustain their cultural, religious, and economic values. The main aim of this paper is to undertake dynamic investigation tests for the dome of Fatima Khatun, a historic mausoleum in Historic Cairo dating back to the 13th century and consisting of mainly bricks and stones. The challenge was that the structure was difficult to access, and only a small portion of the top was accessible for the attachment of accelerometers. Current dynamic identification procedures typically adopt methods in which the sensors are arranged at optimal locations and permit direct assessment of the natural frequencies, mode shapes, and damping ratios of a structure. Approaches that allow for the evaluation of dynamic response for structures with limited accessibility are lacking. To this end, in addition to in situ dynamic investigation tests, a numerical model was cr...
An experimental study was performed to investigate the ultimate strength and modes of failure of ... more An experimental study was performed to investigate the ultimate strength and modes of failure of axially loaded channel rack columns with rear flanges. A total of 16 column specimens fabricated by press-brake forming method were tested up to failure. The material properties of the column specimens were determined using standard tensile coupon tests. The deformation and stress behavior of the tested columns were monitored using displacement transducers and strain gauges. The effects of column slenderness ratio, thickness, perforation, and end conditions on the column ultimate strength and mode of failure were studied. The test failure loads were compared to the ultimate load predictions of the 2001 AISI North American Specification. The comparison showed that the AISI procedure overestimates the failure load, which suggests that the proportioning of the cross-sectional dimensions of the lipped channel sections with rear flanges has a direct effect on the capacity of the columns.
Springer proceedings in earth and environmental sciences, 2022
This paper summarises recent investigations into the structural and material response of ambient-... more This paper summarises recent investigations into the structural and material response of ambient-dry and wet clay-brick and lime-mortar masonry elements, with focus on those used in heritage structures in Historic Cairo. In addition to cyclic tests on largescale masonry walls subjected to lateral displacement and compressive gravity loads, the studies included complementary tests on small scale masonry panels and material specimens. It is shown that moisture can have a notable effect on the main material properties, including the shear and compression strengths, brick-mortar interaction parameters, and the elastic and shear moduli. The extent of the moisture effects is a function of the governing behaviour and material characteristics as well as the interaction between shear and precompression stresses and can lead to a loss of more than a third of the stiffness and strength in addition to a reduction in ductility. Simple and cost-effective strengthening techniques, using textile-reinforced meshes, for enhancing the lateral performance of lowstrength heritage masonry element, are also considered in this study. The effectiveness of the strengthening approach is illustrated and quantified through additional tests on the smallscale panels and large-scale wall specimens. It is shown that simple analytical assessment methods can be reliably adapted for predicting the response of the wall specimens, in terms of the lateral stiffness, strength and overall load-deformation behaviour.
SN applied sciences, Oct 20, 2022
This work intends to provide seismic vulnerability analysis for a building stock in Al Khalifa Di... more This work intends to provide seismic vulnerability analysis for a building stock in Al Khalifa District, Fatimid Cairo while focusing on the historic buildings in the area. The work represents part of an interdisciplinary study targeting the management and conservation of a UNESCO World Heritage Site. The project inspects several aspects including behavior of masonry walls, structural health monitoring of selected structures, conservation studies, in addition to influence of rising ground water. In the current study, seismicity of Egypt generally and Cairo specifically is reviewed. Afterwards, large-scale seismic vulnerability is adopted to calculate the vulnerability index for buildings within the study area. Data are collected through extensive on-site surveys for more than one hundred buildings. Observed typologies are listed alongside possible mechanisms of failure. Egypt has moderate seismic hazard; however, many buildings are prone to damage due to inadequate seismic design. This leads to retrofitting requirements to reduce seismic vulnerability and adhere to imposed seismic requirements in design codes. The study is intended to understand seismic risk of buildings within study area as part of a comprehensive study. Developed vulnerability map show that many buildings are prone to damage during seismic events.
Electronic Journal of Structural Engineering
In many high-rise buildings, architectural requirements may result in a variable configuration fo... more In many high-rise buildings, architectural requirements may result in a variable configuration for the vertical structural elements between the stories of the building. To accommodate such vertical elements’ discontinuity, a “transfer” floor conveying vertical and lateral loads between upper and lower stories must be introduced. A drawback of the transfer floor is the sudden change in the building's lateral stiffness at its level: the structure becomes susceptible to the formation of a soft-storey mechanism under moderate to severe earthquakes. These buildings generally showed conventional elastic behavior for frequent earthquake but suffer extensive crack in the vicinity of transfer floors for rare earthquake. In this paper, a state of the art review is presented on recent publications dealing with the seismic behavior of high rise buildings with transfer floor.
International Journal of Advances in Structural and Geotechnical Engineering
Egypt is one of the richest countries in its historic and tourism attractions which are among the... more Egypt is one of the richest countries in its historic and tourism attractions which are among the main contributors to the country's gross domestic product (GDP). Historic Cairo which has hundreds of mesmerizing historic Coptic and Islamic structures (mosques, churches, mausoleums, etc.) has been identified by UNESCO as a world heritage site since 1979. However, it has been noticed that its share in the tourism revenues is quite low compared to its value. One of the reasons is that many of the historic structures are closed because they are severely deteriorated due to urban expansion, pollution, environmental hazards, and aging. To revive the tourism in Historic Cairo, the government has been directing its efforts towards the conservation of those structures and reopening them to the public, and thus increase tourism-based revenues. However, the funding needed to restore all structures is very limited. There are hundreds of historic structures in need for restoration with a budget of more than one billion EGP. Accordingly, this research proposes a decision support system inspired by infrastructure asset management system (IAMS) to guide the fund allocation process. It follows the sequential steps of IAMS from asset inventory, condition assessment, up to prioritization and fund-allocation, yet considering the unique value of each heritage building and the expected socioeconomic benefits of restoring the structures and upgrading their surrounding areas. Therefore, this new structured decision support system will help policy makers develop the best rational restoration plan that will help rejuvenate Historic Cairo, and subsequently Egypt's tourism revenues.
Electronic Journal of Structural Engineering
In many high-rise buildings, architectural requirements may result in a variable configuration fo... more In many high-rise buildings, architectural requirements may result in a variable configuration for the vertical structural elements between the stories of the building. To accommodate such vertical elements’ discontinuity, a "transfer" floor conveying vertical and lateral loads between upper and lower stories must be introduced. A drawback of the transfer floor is the sudden change in the building's lateral stiffness at its level: the structure becomes susceptible to the formation of a soft-storey mechanism under moderate to severe earthquakes. These buildings generally showed conventional elastic behaviour for frequent earthquake but suffer extensive crack in the vicinity of the transfer floors for rare earthquake. For design purposes, current numerical modelling of high-rise building adopts reduced stiffness for the vertical elements for strength analysis and full stiffness for serviceability and drift analysis: a tradition that needs to be verified. A 3-D numerical ...
Buildings
Historic Cairo has been a UNESCO World Heritage Site since 1979. It has more than 600 historic st... more Historic Cairo has been a UNESCO World Heritage Site since 1979. It has more than 600 historic structures, which require extensive studies to sustain their cultural, religious, and economic values. The main aim of this paper is to undertake dynamic investigation tests for the dome of Fatima Khatun, a historic mausoleum in Historic Cairo dating back to the 13th century and consisting of mainly bricks and stones. The challenge was that the structure was difficult to access, and only a small portion of the top was accessible for the attachment of accelerometers. Current dynamic identification procedures typically adopt methods in which the sensors are arranged at optimal locations and permit direct assessment of the natural frequencies, mode shapes, and damping ratios of a structure. Approaches that allow for the evaluation of dynamic response for structures with limited accessibility are lacking. To this end, in addition to in situ dynamic investigation tests, a numerical model was cr...
Bulletin of Earthquake Engineering, 2021
This paper presents an experimental investigation into the structural and material response of am... more This paper presents an experimental investigation into the structural and material response of ambient-dry and wet clay-brick/lime-mortar masonry elements. In addition to cyclic tests on four large-scale masonry walls subjected to lateral in-plane displacement and co-existing compressive gravity load, the study also includes complementary tests on square masonry panels under diagonal compression and cylindrical masonry cores in compression. After describing the specimen details, wetting method and testing arrangements, the main results and observations are provided and discussed. The results obtained from full-field digital image correlation measurements enable a detailed assessment of the material shear-compression strength envelope, and permit a direct comparison with the strength characteristics of structural walls. The full load-deformation behaviour of the large-scale walls is also evaluated, including their ductility and failure modes, and compared with the predictions of avai...
Springer proceedings in earth and environmental sciences, 2022
This paper summarises recent investigations into the structural and material response of ambient-... more This paper summarises recent investigations into the structural and material response of ambient-dry and wet clay-brick and lime-mortar masonry elements, with focus on those used in heritage structures in Historic Cairo. In addition to cyclic tests on largescale masonry walls subjected to lateral displacement and compressive gravity loads, the studies included complementary tests on small scale masonry panels and material specimens. It is shown that moisture can have a notable effect on the main material properties, including the shear and compression strengths, brick-mortar interaction parameters, and the elastic and shear moduli. The extent of the moisture effects is a function of the governing behaviour and material characteristics as well as the interaction between shear and precompression stresses and can lead to a loss of more than a third of the stiffness and strength in addition to a reduction in ductility. Simple and cost-effective strengthening techniques, using textile-reinforced meshes, for enhancing the lateral performance of lowstrength heritage masonry element, are also considered in this study. The effectiveness of the strengthening approach is illustrated and quantified through additional tests on the smallscale panels and large-scale wall specimens. It is shown that simple analytical assessment methods can be reliably adapted for predicting the response of the wall specimens, in terms of the lateral stiffness, strength and overall load-deformation behaviour.
The Egyptian International Journal of Engineering Sciences and Technology, 2018
Damage detection in structures using vibration analysis has been a subject of intensive investiga... more Damage detection in structures using vibration analysis has been a subject of intensive investigation for the last two decades. In this paper, a method for damage detection using wavelet analysis is presented. MATLAB program is prepared to simulate a beam, calculate its mode shapes and analyze the first mode shape by discrete wavelet analysis. The first mode shapes of damaged and undamaged beams are transformed to the wavelet domain. The difference of the detail coefficients of damaged and undamaged mode shapes displays accurately the damage location. A detailed parametric study was conducted by changing the damage location, intensity as well as the boundary conditions and wavelet families. These studies have indicated that discrete wavelet transform accurately predicts the damage location (single or multi damages) from analyzing the first mode shape.
Electronic Journal of Structural Engineering
In many high-rise buildings, architectural requirements may result in a variable configuration fo... more In many high-rise buildings, architectural requirements may result in a variable configuration for the vertical structural elements between the stories of the building. To accommodate such vertical elements’ discontinuity, a “transfer” floor conveying vertical and lateral loads between upper and lower stories must be introduced. A drawback of the transfer floor is the sudden change in the building's lateral stiffness at its level: the structure becomes susceptible to the formation of a soft-storey mechanism under moderate to severe earthquakes. These buildings generally showed conventional elastic behavior for frequent earthquake but suffer extensive crack in the vicinity of transfer floors for rare earthquake. In this paper, a state of the art review is presented on recent publications dealing with the seismic behavior of high rise buildings with transfer floor.
Electronic Journal of Structural Engineering
In many high-rise buildings, architectural requirements may result in a variable configuration fo... more In many high-rise buildings, architectural requirements may result in a variable configuration for the vertical structural elements between the stories of the building. To accommodate such vertical elements’ discontinuity, a “transfer” floor conveying vertical and lateral loads between upper and lower stories must be introduced. A drawback of the transfer floor is the sudden change in the building's lateral stiffness at its level: the structure becomes susceptible to the formation of a soft-storey mechanism under moderate to severe earthquakes. These buildings generally showed conventional elastic behavior for frequent earthquake but suffer extensive crack in the vicinity of transfer floors for rare earthquake. In this paper, a state of the art review is presented on recent publications dealing with the seismic behavior of high rise buildings with transfer floor.
Electronic Journal of Structural Engineering
In many high-rise buildings, architectural requirements may result in a variable configuration fo... more In many high-rise buildings, architectural requirements may result in a variable configuration for the vertical structural elements between the stories of the building. To accommodate such vertical elements’ discontinuity, a "transfer" floor conveying vertical and lateral loads between upper and lower stories must be introduced. A drawback of the transfer floor is the sudden change in the building's lateral stiffness at its level: the structure becomes susceptible to the formation of a soft-storey mechanism under moderate to severe earthquakes. These buildings generally showed conventional elastic behaviour for frequent earthquake but suffer extensive crack in the vicinity of the transfer floors for rare earthquake. For design purposes, current numerical modelling of high-rise building adopts reduced stiffness for the vertical elements for strength analysis and full stiffness for serviceability and drift analysis: a tradition that needs to be verified. A 3-D numerical ...
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Papers by Sherif Ahmed Mourad