Ferrocement panels are thin-section panels that are widely used in lightweight construction. Due ... more Ferrocement panels are thin-section panels that are widely used in lightweight construction. Due to lesser flexural stiffness, they are susceptible to surface cracking. Water may penetrate through these cracks and may cause corrosion of conventional thin steel wire mesh. This corrosion is one of the major factors which affect the load-carrying and durability of ferrocement panels. There is a need to improve the mechanical performance of ferrocement panels either through using some non-corrodible reinforcing mesh or through improving the cracking behavior of the mortar mix. In the present experimental work, PVC plastic wire mesh is employed to address this problem. SBR latex and polypropylene (PP) fibers are also utilized as admixtures to control the micro-cracking and improve the energy absorption capacity. The main idea is to improve the structural performance of ferrocement panels that may be utilized in lightweight, low-cost house construction and sustainable construction. The ul...
The chloride diffusion coefficient (Dcl) is one of the most important characteristics of concrete... more The chloride diffusion coefficient (Dcl) is one of the most important characteristics of concrete durability. This study aimed to develop a prediction model for the Dcl of concrete incorporating supplemental cementitious material. The datasets of concrete containing supplemental cementitious materials (SCMs) such as tricalcium aluminate (C3A), ground granulated blast furnace slag (GGBFS), and fly ash were used in developing the model. Five machine learning (ML) algorithms including adaptive neuro-fuzzy inference system (ANFIS), artificial neural network (ANN), support vector machine (SVM), and extreme learning machine (ELM) were used in the model development. The performance of the developed models was tested using five evaluation metrics, namely, normalized reference index (RI), coefficient of determination (R2), mean absolute error (MAE), and root mean square error (RMSE). The SVM models demonstrated the highest prediction accuracy with R2 values of 0.955 and 0.951 at the training...
The conventional method for determining the Marshall Stability (MS) and Marshall Flow (MF) of asp... more The conventional method for determining the Marshall Stability (MS) and Marshall Flow (MF) of asphalt pavements entails laborious, time-consuming, and expensive laboratory procedures. In order to develop new and advanced prediction models for MS and MF of asphalt pavements the current study applied three soft computing techniques: Artificial Neural Network (ANN), Adaptive Neuro-Fuzzy Inference System (ANFIS), and Multi Expression Programming (MEP). A comprehensive database of 343 data points was established for both MS and MF. The nine most significant and straightforwardly determinable geotechnical factors were chosen as the predictor variables. The root squared error (RSE), Nash–Sutcliffe efficiency (NSE), mean absolute error (MAE), root mean square error (RMSE), relative root mean square error (RRMSE), coefficient of determination (R2), and correlation coefficient (R), were all used to evaluate the performance of models. The sensitivity analysis (SA) revealed the rising order of ...
Every year, millions of tons of red mud (RDM) are created across the globe. Its storage is a majo... more Every year, millions of tons of red mud (RDM) are created across the globe. Its storage is a major environmental issue due to its high basicity and tendency for leaching. This material is often kept in dams, necessitating previous attention to the disposal location, as well as monitoring and maintenance during its useful life. As a result, it is critical to develop an industrial solution capable of consuming large quantities of this substance. Many academics have worked for decades to create different cost-effective methods for using RMD. One of the most cost-effective methods is to use RMD in cement manufacture, which is also an effective approach for large-scale RMD recycling. This article gives an overview of the use of RMD in concrete manufacturing. Other researchers’ backgrounds were considered and examined based on fresh characteristics, mechanical properties, durability, microstructure analysis, and environmental impact analysis. The results show that RMD enhanced the mechani...
The use of superabsorbent polymers, sometimes known as SAP, is a tremendously efficacious method ... more The use of superabsorbent polymers, sometimes known as SAP, is a tremendously efficacious method for reducing the amount of autogenous shrinkage (AS) that occurs in high-performance concrete. This study utilizes support vector regression (SVR) as a standalone machine-learning algorithm (MLA) which is then ensemble with boosting and bagging approaches to reduce the bias and overfitting issues. In addition, these ensemble methods are optimized with twenty sub-models with varying the nth estimators to achieve a robust R2. Moreover, modified bagging as random forest regression (RFR) is also employed to predict the AS of concrete containing supplementary cementitious materials (SCMs) and SAP. The data for modeling of AS includes water to cement ratio (W/C), water to binder ratio (W/B), cement, silica fume, fly ash, slag, the filer, metakaolin, super absorbent polymer, superplasticizer, super absorbent polymer size, curing time, and super absorbent polymer water intake. Statistical and k-...
The utilization of carbon-fiber-reinforced polymer (CFRP) composites as strengthening materials f... more The utilization of carbon-fiber-reinforced polymer (CFRP) composites as strengthening materials for structural components has become quite famous over the last couple of decades. The present experimental study was carried out to examine the effect of varied widths of externally bonded CFRP on the debonding strain of CFRP and the failure mode of plain concrete beams. Twelve plain concrete prims measuring 100 mm × 100 mm × 500 mm were cast and tested under identical loading conditions. The twelve specimens include two control prisms, i.e., without CFRP strips, and the remaining ten prisms were reinforced with CFRP strips with widths of 10 mm, 20 mm, 30 mm, 40 mm, and 50 mm, respectively, i.e., two prisms in each group. Four-point loading flexural testing was carried out, and the resulting data are presented in the form of peak load vs. midpoint displacement, load vs. concrete strain, and load vs. CFRP strain. The peak load was directly recorded from the testing machine, while the midp...
The thermal insulation and integrity of the thermal barrier coating is hampered by the formation ... more The thermal insulation and integrity of the thermal barrier coating is hampered by the formation of mixed oxide at intermediate bond coat. The existing reported work correlates growth of mixed oxide to the microstructural and phase changes. The track mostly used to study these changes is scanning electron microscopy, X-ray diffraction, and electrochemical testing. Oxide growth is principally an electrochemical process; hence a thirst exists to study this aspect by using advanced electrochemical techniques. In this study scanning electrochemical microscopy is used to reveal the electrochemical activity in the closest vicinity of the surface. A raster scan of 500 µm area was carried out by microelectrode in an electrolyte at a distance of 5 µm above the surface to record the current profile. The activity at the surface was confirmed by current distance curves. The tip of the microelectrode was approached from 60 µm height to 2 µm above the surface. The current–distance curves for the ...
Although ultra-high-performance concrete (UHPC) presents superior mechanical properties and durab... more Although ultra-high-performance concrete (UHPC) presents superior mechanical properties and durability compared to conventional concrete; its spalling resistance to elevated temperatures is much lower compared to conventional concrete due to the high compactness and absence of capillary pores. This paper investigated the influence of lightweight aggregate (LWA) on the strength properties and microstructure of UHPC to enhance its resistance to elevated temperatures. UHPC specimens prepared with LWA as a partial replacement of silica sand were produced. The study evaluated the compressive and flexural strengths, failure mode, mass loss, and microstructure of the specimens, using SEM. The results showed that the compressive strength of the UHPC specimen was reduced with increasing the content of LWA at ambient temperature, but the compressive strength of the UHPC specimens prepared with LWA improved when exposed to elevated temperatures. The replacement of 10% of the silica sand with L...
In recent years, there have been significant concerns about environmental issues, sustainability ... more In recent years, there have been significant concerns about environmental issues, sustainability of infrastructure, and depletion of nonrenewable resources for pavement construction. These concerns have led to substituting petroleum-based paving materials with their biobased counterparts. Research efforts have attempted to produce asphalt from renewable bio-resources. As a special modifier for asphalt, petroleum-based epoxy resin has been used in a few asphalt paving projects that require superior performance of asphalt mixtures. This study attempts to develop a biobased epoxy modifier for asphalt, which may improve asphalt performance at lower economic and environmental costs. Based on the findings from research in the chemistry industry, an epoxidized soybean oil (ESO) and a biobased curing agent, maleic anhydride (MA), were selected to develop the epoxy modifier for asphalt. The proper proportions of ESO, MA, and a base asphalt (PG 67-22) were determined to achieve a homogenous b...
Reinforced concrete (RC) has been commonly used as a construction material for decades due to its... more Reinforced concrete (RC) has been commonly used as a construction material for decades due to its high compressive strength and moderate tensile strength. However, these two properties of RC are frequently hampered by degradation. The main degradation processes in RC structures are carbonation and the corrosion of rebars. The scientific community is divided regarding the process by which carbonation causes structural damage. Some researchers suggest that carbonation weakens a structure and makes it prone to rebar corrosion, while others suggest that carbonation does not damage structures enough to cause rebar corrosion. This paper is a review of the research work carried out by different researchers on the carbonation and corrosion of RC structures. The process of carbonation and the factors that contribute to this process will be discussed, alongside recommendations for improving structures to decrease the carbonation process. The corrosion of rebars, damage to passive layers, volu...
The present study explores the structural pavement design techniques related to pavement distress... more The present study explores the structural pavement design techniques related to pavement distresses in terms of pavement rutting, cracking and International Roughness Index (IRI) based on the materials properties, roadbed characteristics, climate and traffic loads for highway network of Saudi Arabia (KSA). The study was focused on selected site conditions at four regions in KSA: Central (Riyadh); Eastern (Al-Ahsa); Western (Jeddah) and Northern (Arar). Mechanistic-Empirical Pavement Design Guide (MEPDG) software was used to calibrate and predict pavement design life according to the mentioned distresses for different regions in the KSA. This is the first time where the exact weather stations were selected to run analysis on the software determining realistic pavement distresses. In the study, the pavement structure design is different for low traffic (700 AADTT) and high traffic (2000, 6000, and 10,000 AADTT). The tests were run on the MEPDG software to analyze the distresses predic...
IOP Conference Series: Earth and Environmental Science
Pipelines are the main means of transportation for liquids such as fresh water. Maintaining the p... more Pipelines are the main means of transportation for liquids such as fresh water. Maintaining the pipelines in a healthy condition is essential to avoid leakage that could affect the economy, environment, sustainability, health and safety. Therefore, valuable water must be well managed and saved by detecting the minor leaks before outrageous losses. The objective of this research is to develop a Kelvin/Zisman probe (KZP) based methodology to detect water leaks in underground supply pipelines. A KZP measures the presence of moisture in soil by assessing the electric potential value (E) in volts that is set-up by the probe. It is designed to detect minor leaks especially in polyvinyl chloride (PVC) and metallic pipes such as steel pipes (ANSI Schedule 40). The developed KZP passes above the ground surface (soil) to take the potential value readings. The reading results confirm the KZP is sensitive to the moisture; so, it can detect water content of soil with 6.7%, 5.6%, and 5.2%, but ca...
Columns at the ground floor and parking garages that could be hit by a car pose a significant ris... more Columns at the ground floor and parking garages that could be hit by a car pose a significant risk to the structural stability of the building superstructures. Generally, these columns are not built to sustain the lateral impact force generated by car–column collision. In this study, the performance of axially loaded retrofitted reinforced concrete (RC) columns against car impact is evaluated using finite element (FE) simulation. The FE model of the RC column with axial load was validated with experimental results. For the car-crushing simulations, two SUV car models with a mass of about 2250 kg, which had been experimentally validated, were used to simulate the car–column collision. The results of the FE analysis revealed that once the impact speed exceeds 30 km/h, the horizontal impact force has a significant effect on the column joint at the foundation. The impact force increases linearly as the impact velocity of the car increases up to 20 km/h. When car impact velocities are mo...
AbstractIn recent years, concerns about the depletion of nonrenewable resources, infrastructure s... more AbstractIn recent years, concerns about the depletion of nonrenewable resources, infrastructure sustainability, and environmental impact in pavement engineering have led to substituting petroleum-b...
Ferrocement panels are thin-section panels that are widely used in lightweight construction. Due ... more Ferrocement panels are thin-section panels that are widely used in lightweight construction. Due to lesser flexural stiffness, they are susceptible to surface cracking. Water may penetrate through these cracks and may cause corrosion of conventional thin steel wire mesh. This corrosion is one of the major factors which affect the load-carrying and durability of ferrocement panels. There is a need to improve the mechanical performance of ferrocement panels either through using some non-corrodible reinforcing mesh or through improving the cracking behavior of the mortar mix. In the present experimental work, PVC plastic wire mesh is employed to address this problem. SBR latex and polypropylene (PP) fibers are also utilized as admixtures to control the micro-cracking and improve the energy absorption capacity. The main idea is to improve the structural performance of ferrocement panels that may be utilized in lightweight, low-cost house construction and sustainable construction. The ul...
The chloride diffusion coefficient (Dcl) is one of the most important characteristics of concrete... more The chloride diffusion coefficient (Dcl) is one of the most important characteristics of concrete durability. This study aimed to develop a prediction model for the Dcl of concrete incorporating supplemental cementitious material. The datasets of concrete containing supplemental cementitious materials (SCMs) such as tricalcium aluminate (C3A), ground granulated blast furnace slag (GGBFS), and fly ash were used in developing the model. Five machine learning (ML) algorithms including adaptive neuro-fuzzy inference system (ANFIS), artificial neural network (ANN), support vector machine (SVM), and extreme learning machine (ELM) were used in the model development. The performance of the developed models was tested using five evaluation metrics, namely, normalized reference index (RI), coefficient of determination (R2), mean absolute error (MAE), and root mean square error (RMSE). The SVM models demonstrated the highest prediction accuracy with R2 values of 0.955 and 0.951 at the training...
The conventional method for determining the Marshall Stability (MS) and Marshall Flow (MF) of asp... more The conventional method for determining the Marshall Stability (MS) and Marshall Flow (MF) of asphalt pavements entails laborious, time-consuming, and expensive laboratory procedures. In order to develop new and advanced prediction models for MS and MF of asphalt pavements the current study applied three soft computing techniques: Artificial Neural Network (ANN), Adaptive Neuro-Fuzzy Inference System (ANFIS), and Multi Expression Programming (MEP). A comprehensive database of 343 data points was established for both MS and MF. The nine most significant and straightforwardly determinable geotechnical factors were chosen as the predictor variables. The root squared error (RSE), Nash–Sutcliffe efficiency (NSE), mean absolute error (MAE), root mean square error (RMSE), relative root mean square error (RRMSE), coefficient of determination (R2), and correlation coefficient (R), were all used to evaluate the performance of models. The sensitivity analysis (SA) revealed the rising order of ...
Every year, millions of tons of red mud (RDM) are created across the globe. Its storage is a majo... more Every year, millions of tons of red mud (RDM) are created across the globe. Its storage is a major environmental issue due to its high basicity and tendency for leaching. This material is often kept in dams, necessitating previous attention to the disposal location, as well as monitoring and maintenance during its useful life. As a result, it is critical to develop an industrial solution capable of consuming large quantities of this substance. Many academics have worked for decades to create different cost-effective methods for using RMD. One of the most cost-effective methods is to use RMD in cement manufacture, which is also an effective approach for large-scale RMD recycling. This article gives an overview of the use of RMD in concrete manufacturing. Other researchers’ backgrounds were considered and examined based on fresh characteristics, mechanical properties, durability, microstructure analysis, and environmental impact analysis. The results show that RMD enhanced the mechani...
The use of superabsorbent polymers, sometimes known as SAP, is a tremendously efficacious method ... more The use of superabsorbent polymers, sometimes known as SAP, is a tremendously efficacious method for reducing the amount of autogenous shrinkage (AS) that occurs in high-performance concrete. This study utilizes support vector regression (SVR) as a standalone machine-learning algorithm (MLA) which is then ensemble with boosting and bagging approaches to reduce the bias and overfitting issues. In addition, these ensemble methods are optimized with twenty sub-models with varying the nth estimators to achieve a robust R2. Moreover, modified bagging as random forest regression (RFR) is also employed to predict the AS of concrete containing supplementary cementitious materials (SCMs) and SAP. The data for modeling of AS includes water to cement ratio (W/C), water to binder ratio (W/B), cement, silica fume, fly ash, slag, the filer, metakaolin, super absorbent polymer, superplasticizer, super absorbent polymer size, curing time, and super absorbent polymer water intake. Statistical and k-...
The utilization of carbon-fiber-reinforced polymer (CFRP) composites as strengthening materials f... more The utilization of carbon-fiber-reinforced polymer (CFRP) composites as strengthening materials for structural components has become quite famous over the last couple of decades. The present experimental study was carried out to examine the effect of varied widths of externally bonded CFRP on the debonding strain of CFRP and the failure mode of plain concrete beams. Twelve plain concrete prims measuring 100 mm × 100 mm × 500 mm were cast and tested under identical loading conditions. The twelve specimens include two control prisms, i.e., without CFRP strips, and the remaining ten prisms were reinforced with CFRP strips with widths of 10 mm, 20 mm, 30 mm, 40 mm, and 50 mm, respectively, i.e., two prisms in each group. Four-point loading flexural testing was carried out, and the resulting data are presented in the form of peak load vs. midpoint displacement, load vs. concrete strain, and load vs. CFRP strain. The peak load was directly recorded from the testing machine, while the midp...
The thermal insulation and integrity of the thermal barrier coating is hampered by the formation ... more The thermal insulation and integrity of the thermal barrier coating is hampered by the formation of mixed oxide at intermediate bond coat. The existing reported work correlates growth of mixed oxide to the microstructural and phase changes. The track mostly used to study these changes is scanning electron microscopy, X-ray diffraction, and electrochemical testing. Oxide growth is principally an electrochemical process; hence a thirst exists to study this aspect by using advanced electrochemical techniques. In this study scanning electrochemical microscopy is used to reveal the electrochemical activity in the closest vicinity of the surface. A raster scan of 500 µm area was carried out by microelectrode in an electrolyte at a distance of 5 µm above the surface to record the current profile. The activity at the surface was confirmed by current distance curves. The tip of the microelectrode was approached from 60 µm height to 2 µm above the surface. The current–distance curves for the ...
Although ultra-high-performance concrete (UHPC) presents superior mechanical properties and durab... more Although ultra-high-performance concrete (UHPC) presents superior mechanical properties and durability compared to conventional concrete; its spalling resistance to elevated temperatures is much lower compared to conventional concrete due to the high compactness and absence of capillary pores. This paper investigated the influence of lightweight aggregate (LWA) on the strength properties and microstructure of UHPC to enhance its resistance to elevated temperatures. UHPC specimens prepared with LWA as a partial replacement of silica sand were produced. The study evaluated the compressive and flexural strengths, failure mode, mass loss, and microstructure of the specimens, using SEM. The results showed that the compressive strength of the UHPC specimen was reduced with increasing the content of LWA at ambient temperature, but the compressive strength of the UHPC specimens prepared with LWA improved when exposed to elevated temperatures. The replacement of 10% of the silica sand with L...
In recent years, there have been significant concerns about environmental issues, sustainability ... more In recent years, there have been significant concerns about environmental issues, sustainability of infrastructure, and depletion of nonrenewable resources for pavement construction. These concerns have led to substituting petroleum-based paving materials with their biobased counterparts. Research efforts have attempted to produce asphalt from renewable bio-resources. As a special modifier for asphalt, petroleum-based epoxy resin has been used in a few asphalt paving projects that require superior performance of asphalt mixtures. This study attempts to develop a biobased epoxy modifier for asphalt, which may improve asphalt performance at lower economic and environmental costs. Based on the findings from research in the chemistry industry, an epoxidized soybean oil (ESO) and a biobased curing agent, maleic anhydride (MA), were selected to develop the epoxy modifier for asphalt. The proper proportions of ESO, MA, and a base asphalt (PG 67-22) were determined to achieve a homogenous b...
Reinforced concrete (RC) has been commonly used as a construction material for decades due to its... more Reinforced concrete (RC) has been commonly used as a construction material for decades due to its high compressive strength and moderate tensile strength. However, these two properties of RC are frequently hampered by degradation. The main degradation processes in RC structures are carbonation and the corrosion of rebars. The scientific community is divided regarding the process by which carbonation causes structural damage. Some researchers suggest that carbonation weakens a structure and makes it prone to rebar corrosion, while others suggest that carbonation does not damage structures enough to cause rebar corrosion. This paper is a review of the research work carried out by different researchers on the carbonation and corrosion of RC structures. The process of carbonation and the factors that contribute to this process will be discussed, alongside recommendations for improving structures to decrease the carbonation process. The corrosion of rebars, damage to passive layers, volu...
The present study explores the structural pavement design techniques related to pavement distress... more The present study explores the structural pavement design techniques related to pavement distresses in terms of pavement rutting, cracking and International Roughness Index (IRI) based on the materials properties, roadbed characteristics, climate and traffic loads for highway network of Saudi Arabia (KSA). The study was focused on selected site conditions at four regions in KSA: Central (Riyadh); Eastern (Al-Ahsa); Western (Jeddah) and Northern (Arar). Mechanistic-Empirical Pavement Design Guide (MEPDG) software was used to calibrate and predict pavement design life according to the mentioned distresses for different regions in the KSA. This is the first time where the exact weather stations were selected to run analysis on the software determining realistic pavement distresses. In the study, the pavement structure design is different for low traffic (700 AADTT) and high traffic (2000, 6000, and 10,000 AADTT). The tests were run on the MEPDG software to analyze the distresses predic...
IOP Conference Series: Earth and Environmental Science
Pipelines are the main means of transportation for liquids such as fresh water. Maintaining the p... more Pipelines are the main means of transportation for liquids such as fresh water. Maintaining the pipelines in a healthy condition is essential to avoid leakage that could affect the economy, environment, sustainability, health and safety. Therefore, valuable water must be well managed and saved by detecting the minor leaks before outrageous losses. The objective of this research is to develop a Kelvin/Zisman probe (KZP) based methodology to detect water leaks in underground supply pipelines. A KZP measures the presence of moisture in soil by assessing the electric potential value (E) in volts that is set-up by the probe. It is designed to detect minor leaks especially in polyvinyl chloride (PVC) and metallic pipes such as steel pipes (ANSI Schedule 40). The developed KZP passes above the ground surface (soil) to take the potential value readings. The reading results confirm the KZP is sensitive to the moisture; so, it can detect water content of soil with 6.7%, 5.6%, and 5.2%, but ca...
Columns at the ground floor and parking garages that could be hit by a car pose a significant ris... more Columns at the ground floor and parking garages that could be hit by a car pose a significant risk to the structural stability of the building superstructures. Generally, these columns are not built to sustain the lateral impact force generated by car–column collision. In this study, the performance of axially loaded retrofitted reinforced concrete (RC) columns against car impact is evaluated using finite element (FE) simulation. The FE model of the RC column with axial load was validated with experimental results. For the car-crushing simulations, two SUV car models with a mass of about 2250 kg, which had been experimentally validated, were used to simulate the car–column collision. The results of the FE analysis revealed that once the impact speed exceeds 30 km/h, the horizontal impact force has a significant effect on the column joint at the foundation. The impact force increases linearly as the impact velocity of the car increases up to 20 km/h. When car impact velocities are mo...
AbstractIn recent years, concerns about the depletion of nonrenewable resources, infrastructure s... more AbstractIn recent years, concerns about the depletion of nonrenewable resources, infrastructure sustainability, and environmental impact in pavement engineering have led to substituting petroleum-b...
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