The building seismic performance assessment can be defined as a posterior phase of investigation ... more The building seismic performance assessment can be defined as a posterior phase of investigation in which a detailed analysis is executed in order to evaluation of seismic damages and quantify the sequences of the earthquake for a building, this approach could be probabilistic evaluation or deterministic one. The aim of this paper is to perform seismic damage evaluation for educational multi-storey reinforced Concrete Building in Al-Mustaqbal University College (MUC) in Al-Hilla City, Babylon governorate in the middle of Iraq by using FEMA P-58 methodology. A 3D mathematical modelling, pushover analysis by using SeismoStruct software. In addition, incremental dynamic analysis (IDA) and fragility curve according to FEMA P-58 are developed in order to obtain damage limits in term of performance levels of the case study building. Fragility curves are useful tools for showing the probability of structural damage due to earthquakes as a function of ground motion indices. IDA is performed for those simulated building using twelve ground motions with scaling peak ground acceleration increased every 0.1g until it achieved 1.5g to determine the drift capacity of the building in four performance levels, operational (OP), immediate occupancy (IO), life safety (LS) and near collapse (NC) as defined in FEMA P-58. Based on those capacities, fragility curves were developed in terms of peak ground acceleration (PGA) and elastic spectral displacement for drift levels with lognormal distribution assumption.
IOP Conference Series: Earth and Environmental Science, 2021
The building seismic performance assessment can be defined as a posterior phase of investigation ... more The building seismic performance assessment can be defined as a posterior phase of investigation in which a detailed analysis is executed in order to evaluation of seismic damages and quantify the sequences of the earthquake for a building, this approach could be probabilistic evaluation or deterministic one. The aim of this paper is to perform seismic damage evaluation for educational multi-storey reinforced Concrete Building in Al-Mustaqbal University College (MUC) in Al-Hilla City, Babylon governorate in the middle of Iraq by using FEMA P-58 methodology. A 3D mathematical modelling, pushover analysis by using SeismoStruct software. In addition, incremental dynamic analysis (IDA) and fragility curve according to FEMA P-58 are developed in order to obtain damage limits in term of performance levels of the case study building. Fragility curves are useful tools for showing the probability of structural damage due to earthquakes as a function of ground motion indices. IDA is performed...
The costs of damages in both social and economic aspects are increased as a result of several sig... more The costs of damages in both social and economic aspects are increased as a result of several significant earthquakes worldwide, the economic and social losses are a function of damage of the buildings because the buildings are vulnerable to earthquake damage [1]. In this study a probabilistic methodology FEMA P-58 is applied for seismic performance assessment for Iraqi educational reinforced concrete building in order to calculate the performance in terms of two aspects, the first one is the direct economic losses which include repair costs and repair time and the second one is social losses which include casualties and injuries. This methodology is prepared by ATC, the American Applied Technology Council and its prepared for Federal Emergency Management Agency (FEMA) in 2012. The study is a continuation of other research papers related to applying the same method to the same building that the researcher undertook for the purpose of evaluating the performance of the building when exposed to earthquake and calculating the losses resulting from these damages by choosing different aspects of each research in terms of the method of simplified analysis or the calculation of damages and losses.
Despite being strong under compression, concrete is rather weak when subjected to tensile stress.... more Despite being strong under compression, concrete is rather weak when subjected to tensile stress. Concrete has been reinforced with a variety of materials over time in order to resist tensile stresses. Among various types of fibers, polypropylene fiber, which is available in a range of sizes, is being used to strengthen concrete. The fiber also increases the concrete’s toughness, durability, and low permeability. Polypropylene fibers may be utilized in place of conventional reinforcement, according to a number of researchers. The aim of this study is to collect information from already carried out research on polypropylene fibers. Important characteristics of concrete, such as workability, compressive, tensile, and flexural strength, are reviewed. The review also explores cracking behavior and failure modes of polypropylene fiber reinforced concrete. Furthermore, durability aspects, such as water absorption, porosity, dry shrinkage, and microstructure study (scan electronic microsco...
According to the authors’ best information, the majority of research focuses on other waste mater... more According to the authors’ best information, the majority of research focuses on other waste materials, such as recycling industrial waste (glass, silica fume, marble and waste foundry sand), etc. However, some researchers suggest dune sand as an alternative material for concrete production, but knowledge is still scarce. Therefore, a comprehensive review is required on dune sand to evaluate its current progress as well as its effects on the strength and durability properties of concrete. The review presents detailed literature on dune sand in concrete. The important characteristics of concrete such as slump, compressive, flexural, cracking behaviors, density, water absorption and sulfate resistance were considered for analysis. Results indicate that dune sand can be used in concrete up to 40% without any negative effect on strength and durability. The negative impact of dune sand on strength and durability was due to poor grading and fineness, which restricts the complete (100%) sub...
Self-compacting concrete (SCC) uses a lot of natural resources, much like regular concrete, which... more Self-compacting concrete (SCC) uses a lot of natural resources, much like regular concrete, which results in unsustainable construction. Even though silica fume (SF) and other secondary cementitious materials are the subjects of a lot of studies, to determine the past, present, and future direction of research, information must first be reviewed. This paper compiles data on SSC with SF substations. Slump flow, slump T50, L-box, and V-funnel tests were used to investigate fresh SCC properties, such as filling and passing capabilities. Mechanical properties were examined using compressive, tensile, and flexure strength, while the durability characteristics of SCC were examined through water absorption, porosity, sorptivity, and chloride resistance. The internal structure of SCC, with and without SF, is reviewed through scan electronic microscopy (SEM). The results indicate that SF lacked the filling and passing ability of SCC, but is still within the limit defined by the technical spe...
This study investigated the effect of elevated temperature on the mechanical, physical and durabi... more This study investigated the effect of elevated temperature on the mechanical, physical and durability properties of normal strength concrete, modified with bentonite. The bentonite concrete was cast by substituting cement with bentonite content in proportions of 5, 10 and 15% by weight. Mechanical tests were conducted (compressive and splitting tensile strength). Furthermore, durability performance (mass loss and sorptivity) and specimen properties (elastic modulus, stress–strain behaviour, ductility and energy absorption) were evaluated and discussed. The results demonstrated that samples incorporating bentonite showed better fire endurance than the control mix. The inclusion of bentonite in concrete decreased the mass loss of the specimens exposed to high temperatures. The performance of bentonite concrete was better in terms of mechanical behaviour (compressive and tensile strength) than that of conventional concrete, and it had high resistance to water absorption. Higher ductili...
Utilizing scrap tire rubber by incorporating it into concrete is a valuable option. Many research... more Utilizing scrap tire rubber by incorporating it into concrete is a valuable option. Many researchers are interested in using rubber tire waste in concrete. The possible uses of rubber tires in concrete, however, are dispersed and unclear. Therefore, a compressive analysis is necessary to identify the benefits and drawbacks of rubber tires for concrete performance. For examination, the important areas of concrete freshness, durability, and strength properties were considered. Additionally, several treatments and a microstructure investigation were included. Although it has much promise, there are certain obstacles that prevent it from being used as an aggregate in large numbers, such as the rubber’s weak structural strength and poor binding performance with the cement matrix. Rubber, however, exhibits mechanical strength comparable to reference concrete up to 20%. The evaluation also emphasizes the need for new research to advance rubberized concrete for future generations.
The partial replacement of cement in concrete with other building materials has come to light bec... more The partial replacement of cement in concrete with other building materials has come to light because of research on industrial waste and sustainable building practices. Concrete is made more affordable by using such components, and it also helps to ease disposal worries. Ash made by burning wood and other wood products is one example of such a substance. Many researchers focused on the utilization of wooden ash (WA) as a construction material. However, information is scattered, and no one can easily judge the impact of WA on concrete properties which restrict its use. Therefore, a details review is required which collect the past and current progress on WA as a construction material. relevant information. This review aims to collect all the relevant information including the general back of WA, physical and chemical aspects of WA, the impact of WA on concrete fresh properties, strength properties, and durability aspects in addition to microstructure analysis. The results indicate t...
IOP Conference Series: Earth and Environmental Science, 2021
Within last years, construction projects have quickly accelerated in both number and size. This s... more Within last years, construction projects have quickly accelerated in both number and size. This study deals with some of effects of performance management and its outputs from service and cost viewing. By focusing on the relationship between the two main stages in construction projects, that is the design and implementing stages, the research is going on using method of questionnaire survey including four main factors: the state of design process, the state of implementing process, the state of interaction between the two stages (design and implementation) and the state of problems resulted during and after construction. A questionnaire was distributed into 50 construction projects and the data are collected and analysed through SPSS. The results have shown that there is a weak relationship between design and construction stages in local construction projects. Research showed also that it could not be claimed that this situation (weakness of the interaction of stages) is responsible...
Prior studies in the literature show promising results regarding the improvements in strength and... more Prior studies in the literature show promising results regarding the improvements in strength and durability of concrete upon incorporation of glass fibers into concrete formulations. However, the knowledge regarding glass fiber usage in concrete is scattered. Moreover, this makes it challenging to understand the behavior of glass fiber-reinforced concrete. Therefore, a detailed review is required on glass fiber-reinforced concrete. This paper provides a compressive analysis of glass fiber-reinforced composites. All-important properties of concrete such as flowability, compressive, flexural, tensile strength and modulus of elasticity were presented in this review article. Furthermore, durability aspects such as chloride ion penetration, water absorption, ultrasonic pulse velocity (UPV) and acid resistance were also considered. Finally, the bond strength of the fiber and cement paste was examined via scanning electron microscopy. Results indicate that glass fibers improved concrete’s...
While adding superabsorbent polymer hydrogel particles to fresh concrete admixtures, they act as ... more While adding superabsorbent polymer hydrogel particles to fresh concrete admixtures, they act as internal curing agents that absorb and then release large amounts of water and reduce self-desiccation and volumetric shrinkage of cement that finally result in hardened concrete with increased durability and strength. The entrainment of microscopic air bubbles in the concrete paste can substantially improve the resistance of concrete. When the volume and distribution of entrained air are adequately managed, the microstructure is protected from the pressure produced by freezing water. This study addresses the design and application of hydrogel nanoparticles as internal curing agents in concrete, as well as new findings on crucial hydrogel–ion interactions. When mixed into concrete, hydrogel particles produce their stored water to power the curing reaction, resulting in less volumetric shrinkage and cracking and thereby prolonging the service life of concrete. The mechanical and swelling ...
Existing bond-slip (τ-s) relations for fibre-reinforced polymer (FRP)-steel joints employ differe... more Existing bond-slip (τ-s) relations for fibre-reinforced polymer (FRP)-steel joints employ different shapes and mathematical expressions, inferring that their predictions of failure load and mode, and other interface properties, might be inconsistent or inaccurate. In this study, predictions of four widely used τ-s relations are evaluated using a large experimental database of 78 double-lap FRP-steel specimens. To facilitate the evaluation process, a robust finite element (FE) model is developed for each test, implementing data from either of the existing τ-s relations to define the FRP-steel interface. Comparisons between test and FE results indicated that the existing τ-s models were unable of predicting the ultimate load (Pu) and effective bond length (Leff) of FRP-steel joints, or the relation between Pu and bond length and that between Leff and FRP modulus (Ef). A new τ-s model is developed based on an inverse FE simulation, comparison with experimental results, and regression a...
In the last few decades, the concrete industry has been massively expanded with the adoption of v... more In the last few decades, the concrete industry has been massively expanded with the adoption of various kinds of binding materials. As a substitute to cement and in an effort to relieve ecofriendly difficulties linked with cement creation, the utilization of industrial waste as cementitious material can sharply reduce the amount of trash disposed of in lakes and landfills. With respect to the mechanical properties, durability and thermal behavior, ground-granulated blast-furnace slag (GGBS) delineates a rational way to develop sustainable cement and concrete. Apart from environmental benefits, the replacement of cement by GGBS illustrates an adequate way to mitigate the economic impact. Although many researchers concentrate on utilizing GGBS in concrete production, knowledge is scattered, and additional research is needed to better understand relationships among a wide spectrum of key questions and to more accurately determine these preliminary findings. This work aims to shed some ...
IOP Conference Series: Materials Science and Engineering
The Ordinary Portland Cement (OPC) is one of the major ingredient utilized for the manufacture of... more The Ordinary Portland Cement (OPC) is one of the major ingredient utilized for the manufacture of concrete. The manufacturing of cement includes the release of huge amounts of CO2 gas as a main contributor for greenhouse influence and global warming. Several researchers have investigated the characteristics of OPC concrete utilizing cementitious materials like fly ash, silica fume, and Ground Granulated Blast furnace Slag (GGBS) as replacement materials. The article aims to investigate experimentally the flexural behavior of concrete beams with GGBS. The experimental work was divided into three stages, the first one consists of six reinforced concrete beam specimens with (0%, 40% and 60%) of GGBS. During this stage, the used steel bars were 8 mm diameter and 500 mm in length. In the second stage, the length of the steel bars was reduced to 400 mm with the best mixture of (GGBS+OPC) that obtained from stage 1. In the third stage, the best length of steel bars was used with the best (...
The push for sustainability in the construction sector has demanded the use of increasingly renew... more The push for sustainability in the construction sector has demanded the use of increasingly renewable resources. These natural fibers are biodegradable and non-toxic, and their mechanical capabilities are superior to those of synthetic fibers in terms of strength and durability. A lot of research recommends coconut fibers as an alternative to synthetic fibers. However, the knowledge is scattered, and no one can easily judge the suitability of coconut fibers in concrete. This paper presents a summary of research progress on coconut fiber (natural fibers) reinforced concrete. The effects of coconut fibers on the properties of concrete are reviewed. Factors affecting the fresh, hardened, and durability properties of concrete reinforced with coconut fiber are discussed. Results indicate that coconut fiber improved the mechanical performance of concrete due to crack prevention, similar to the synthetic fibers but decreased the flowability of concrete. However, coconut fibers improved fle...
Concrete is a commonly used building material; however, it is subject to abrupt failure and limit... more Concrete is a commonly used building material; however, it is subject to abrupt failure and limited energy absorption when yielding. The use of short discrete fibers has displayed a lot of potential in overcoming these issues. Sisal is a natural fiber that is renewable, inexpensive, and readily accessible. SSF is a potential reinforcement for use in concrete because of its cheap cost, low density, high specific strength and modulus, negligible health risk, easy accessibility in certain states, and renewability. In current centuries, there has been growing importance in discovering new uses for SSF-reinforced concrete, which is normally utilized to make ropes, mats, carpets, and other decorative items. This article gives an overview of current advancements in SSF and composites. The qualities of SSF, the interface between SSF and the matrix, and SSF-reinforced properties such as fresh, mechanical strength, and durability have all been examined. The results show that SSF increased str...
Based on the salp swarm algorithm (SSA), this paper proposes an efficient metaheuristic algorithm... more Based on the salp swarm algorithm (SSA), this paper proposes an efficient metaheuristic algorithm for solving global optimization problems and optimizing two commonly encountered geotechnical engineering structures: reinforced concrete cantilever retaining walls and shallow spread foundations. Two new equations for the leader- and followers-position-updating procedures were introduced in the proposed adaptive salp swarm optimization (ASSA). This change improved the algorithm’s exploration capabilities while preventing it from converging prematurely. Benchmark test functions were used to confirm the proposed algorithm’s performance, and the results were compared to the SSA and other effective optimization algorithms. A Wilcoxon’s rank sum test was performed to evaluate the pairwise statistical performances of the algorithms, and it indicated the significant superiority of the ASSA. The new algorithm can also be used to optimize low-cost retaining walls and foundations. In the analysi...
Plastics have become an essential part of our daily lives, and global plastic production has incr... more Plastics have become an essential part of our daily lives, and global plastic production has increased dramatically in the past 50 years. This has significantly increased the amount of plastic garbage produced. Researchers have recently been interested in using trash and recyclable plastics in concrete as an ecologically acceptable building material. A large number of publications have been published that describe the behavior of concrete, containing waste and recovered plastic com ponents. However, information is scattered, and no one knows how plastic trash behaves as concrete materials. This research examines the use of plastic waste (PW) as aggregate or fiber in cement mortar and concrete manufacturing. The article reviewed the three most significant features of concrete: fresh properties, mechanical strength, and durability. PW and cement connections were also studied using microstructure analysis (scan electronic microscopy). The results showed that PW, as a fiber, enhanced me...
The renewable energy is expanding in the sub-systems of distribution electrical grids, due to hav... more The renewable energy is expanding in the sub-systems of distribution electrical grids, due to having low energy costs and high reliability. In this study, off-grid design of the hybrid energy system based-renewable resources is proposed for a house in Hamadan city in Iran. The resources are designed based on economic and climate data such as battery, solar cells, wind turbines, and electrolyser/fuel cell. The design of mentioned resources is done with attention to twofold optimization modelling including operation cost (OC) and net present cost (NPC). The modelling of resources is implemented in HOMER software based on optimal sizing and installation costs. In the numerical simulation, the three optimal designs are presented to meet electrical demand with minimum costs and high reliability.
The building seismic performance assessment can be defined as a posterior phase of investigation ... more The building seismic performance assessment can be defined as a posterior phase of investigation in which a detailed analysis is executed in order to evaluation of seismic damages and quantify the sequences of the earthquake for a building, this approach could be probabilistic evaluation or deterministic one. The aim of this paper is to perform seismic damage evaluation for educational multi-storey reinforced Concrete Building in Al-Mustaqbal University College (MUC) in Al-Hilla City, Babylon governorate in the middle of Iraq by using FEMA P-58 methodology. A 3D mathematical modelling, pushover analysis by using SeismoStruct software. In addition, incremental dynamic analysis (IDA) and fragility curve according to FEMA P-58 are developed in order to obtain damage limits in term of performance levels of the case study building. Fragility curves are useful tools for showing the probability of structural damage due to earthquakes as a function of ground motion indices. IDA is performed for those simulated building using twelve ground motions with scaling peak ground acceleration increased every 0.1g until it achieved 1.5g to determine the drift capacity of the building in four performance levels, operational (OP), immediate occupancy (IO), life safety (LS) and near collapse (NC) as defined in FEMA P-58. Based on those capacities, fragility curves were developed in terms of peak ground acceleration (PGA) and elastic spectral displacement for drift levels with lognormal distribution assumption.
IOP Conference Series: Earth and Environmental Science, 2021
The building seismic performance assessment can be defined as a posterior phase of investigation ... more The building seismic performance assessment can be defined as a posterior phase of investigation in which a detailed analysis is executed in order to evaluation of seismic damages and quantify the sequences of the earthquake for a building, this approach could be probabilistic evaluation or deterministic one. The aim of this paper is to perform seismic damage evaluation for educational multi-storey reinforced Concrete Building in Al-Mustaqbal University College (MUC) in Al-Hilla City, Babylon governorate in the middle of Iraq by using FEMA P-58 methodology. A 3D mathematical modelling, pushover analysis by using SeismoStruct software. In addition, incremental dynamic analysis (IDA) and fragility curve according to FEMA P-58 are developed in order to obtain damage limits in term of performance levels of the case study building. Fragility curves are useful tools for showing the probability of structural damage due to earthquakes as a function of ground motion indices. IDA is performed...
The costs of damages in both social and economic aspects are increased as a result of several sig... more The costs of damages in both social and economic aspects are increased as a result of several significant earthquakes worldwide, the economic and social losses are a function of damage of the buildings because the buildings are vulnerable to earthquake damage [1]. In this study a probabilistic methodology FEMA P-58 is applied for seismic performance assessment for Iraqi educational reinforced concrete building in order to calculate the performance in terms of two aspects, the first one is the direct economic losses which include repair costs and repair time and the second one is social losses which include casualties and injuries. This methodology is prepared by ATC, the American Applied Technology Council and its prepared for Federal Emergency Management Agency (FEMA) in 2012. The study is a continuation of other research papers related to applying the same method to the same building that the researcher undertook for the purpose of evaluating the performance of the building when exposed to earthquake and calculating the losses resulting from these damages by choosing different aspects of each research in terms of the method of simplified analysis or the calculation of damages and losses.
Despite being strong under compression, concrete is rather weak when subjected to tensile stress.... more Despite being strong under compression, concrete is rather weak when subjected to tensile stress. Concrete has been reinforced with a variety of materials over time in order to resist tensile stresses. Among various types of fibers, polypropylene fiber, which is available in a range of sizes, is being used to strengthen concrete. The fiber also increases the concrete’s toughness, durability, and low permeability. Polypropylene fibers may be utilized in place of conventional reinforcement, according to a number of researchers. The aim of this study is to collect information from already carried out research on polypropylene fibers. Important characteristics of concrete, such as workability, compressive, tensile, and flexural strength, are reviewed. The review also explores cracking behavior and failure modes of polypropylene fiber reinforced concrete. Furthermore, durability aspects, such as water absorption, porosity, dry shrinkage, and microstructure study (scan electronic microsco...
According to the authors’ best information, the majority of research focuses on other waste mater... more According to the authors’ best information, the majority of research focuses on other waste materials, such as recycling industrial waste (glass, silica fume, marble and waste foundry sand), etc. However, some researchers suggest dune sand as an alternative material for concrete production, but knowledge is still scarce. Therefore, a comprehensive review is required on dune sand to evaluate its current progress as well as its effects on the strength and durability properties of concrete. The review presents detailed literature on dune sand in concrete. The important characteristics of concrete such as slump, compressive, flexural, cracking behaviors, density, water absorption and sulfate resistance were considered for analysis. Results indicate that dune sand can be used in concrete up to 40% without any negative effect on strength and durability. The negative impact of dune sand on strength and durability was due to poor grading and fineness, which restricts the complete (100%) sub...
Self-compacting concrete (SCC) uses a lot of natural resources, much like regular concrete, which... more Self-compacting concrete (SCC) uses a lot of natural resources, much like regular concrete, which results in unsustainable construction. Even though silica fume (SF) and other secondary cementitious materials are the subjects of a lot of studies, to determine the past, present, and future direction of research, information must first be reviewed. This paper compiles data on SSC with SF substations. Slump flow, slump T50, L-box, and V-funnel tests were used to investigate fresh SCC properties, such as filling and passing capabilities. Mechanical properties were examined using compressive, tensile, and flexure strength, while the durability characteristics of SCC were examined through water absorption, porosity, sorptivity, and chloride resistance. The internal structure of SCC, with and without SF, is reviewed through scan electronic microscopy (SEM). The results indicate that SF lacked the filling and passing ability of SCC, but is still within the limit defined by the technical spe...
This study investigated the effect of elevated temperature on the mechanical, physical and durabi... more This study investigated the effect of elevated temperature on the mechanical, physical and durability properties of normal strength concrete, modified with bentonite. The bentonite concrete was cast by substituting cement with bentonite content in proportions of 5, 10 and 15% by weight. Mechanical tests were conducted (compressive and splitting tensile strength). Furthermore, durability performance (mass loss and sorptivity) and specimen properties (elastic modulus, stress–strain behaviour, ductility and energy absorption) were evaluated and discussed. The results demonstrated that samples incorporating bentonite showed better fire endurance than the control mix. The inclusion of bentonite in concrete decreased the mass loss of the specimens exposed to high temperatures. The performance of bentonite concrete was better in terms of mechanical behaviour (compressive and tensile strength) than that of conventional concrete, and it had high resistance to water absorption. Higher ductili...
Utilizing scrap tire rubber by incorporating it into concrete is a valuable option. Many research... more Utilizing scrap tire rubber by incorporating it into concrete is a valuable option. Many researchers are interested in using rubber tire waste in concrete. The possible uses of rubber tires in concrete, however, are dispersed and unclear. Therefore, a compressive analysis is necessary to identify the benefits and drawbacks of rubber tires for concrete performance. For examination, the important areas of concrete freshness, durability, and strength properties were considered. Additionally, several treatments and a microstructure investigation were included. Although it has much promise, there are certain obstacles that prevent it from being used as an aggregate in large numbers, such as the rubber’s weak structural strength and poor binding performance with the cement matrix. Rubber, however, exhibits mechanical strength comparable to reference concrete up to 20%. The evaluation also emphasizes the need for new research to advance rubberized concrete for future generations.
The partial replacement of cement in concrete with other building materials has come to light bec... more The partial replacement of cement in concrete with other building materials has come to light because of research on industrial waste and sustainable building practices. Concrete is made more affordable by using such components, and it also helps to ease disposal worries. Ash made by burning wood and other wood products is one example of such a substance. Many researchers focused on the utilization of wooden ash (WA) as a construction material. However, information is scattered, and no one can easily judge the impact of WA on concrete properties which restrict its use. Therefore, a details review is required which collect the past and current progress on WA as a construction material. relevant information. This review aims to collect all the relevant information including the general back of WA, physical and chemical aspects of WA, the impact of WA on concrete fresh properties, strength properties, and durability aspects in addition to microstructure analysis. The results indicate t...
IOP Conference Series: Earth and Environmental Science, 2021
Within last years, construction projects have quickly accelerated in both number and size. This s... more Within last years, construction projects have quickly accelerated in both number and size. This study deals with some of effects of performance management and its outputs from service and cost viewing. By focusing on the relationship between the two main stages in construction projects, that is the design and implementing stages, the research is going on using method of questionnaire survey including four main factors: the state of design process, the state of implementing process, the state of interaction between the two stages (design and implementation) and the state of problems resulted during and after construction. A questionnaire was distributed into 50 construction projects and the data are collected and analysed through SPSS. The results have shown that there is a weak relationship between design and construction stages in local construction projects. Research showed also that it could not be claimed that this situation (weakness of the interaction of stages) is responsible...
Prior studies in the literature show promising results regarding the improvements in strength and... more Prior studies in the literature show promising results regarding the improvements in strength and durability of concrete upon incorporation of glass fibers into concrete formulations. However, the knowledge regarding glass fiber usage in concrete is scattered. Moreover, this makes it challenging to understand the behavior of glass fiber-reinforced concrete. Therefore, a detailed review is required on glass fiber-reinforced concrete. This paper provides a compressive analysis of glass fiber-reinforced composites. All-important properties of concrete such as flowability, compressive, flexural, tensile strength and modulus of elasticity were presented in this review article. Furthermore, durability aspects such as chloride ion penetration, water absorption, ultrasonic pulse velocity (UPV) and acid resistance were also considered. Finally, the bond strength of the fiber and cement paste was examined via scanning electron microscopy. Results indicate that glass fibers improved concrete’s...
While adding superabsorbent polymer hydrogel particles to fresh concrete admixtures, they act as ... more While adding superabsorbent polymer hydrogel particles to fresh concrete admixtures, they act as internal curing agents that absorb and then release large amounts of water and reduce self-desiccation and volumetric shrinkage of cement that finally result in hardened concrete with increased durability and strength. The entrainment of microscopic air bubbles in the concrete paste can substantially improve the resistance of concrete. When the volume and distribution of entrained air are adequately managed, the microstructure is protected from the pressure produced by freezing water. This study addresses the design and application of hydrogel nanoparticles as internal curing agents in concrete, as well as new findings on crucial hydrogel–ion interactions. When mixed into concrete, hydrogel particles produce their stored water to power the curing reaction, resulting in less volumetric shrinkage and cracking and thereby prolonging the service life of concrete. The mechanical and swelling ...
Existing bond-slip (τ-s) relations for fibre-reinforced polymer (FRP)-steel joints employ differe... more Existing bond-slip (τ-s) relations for fibre-reinforced polymer (FRP)-steel joints employ different shapes and mathematical expressions, inferring that their predictions of failure load and mode, and other interface properties, might be inconsistent or inaccurate. In this study, predictions of four widely used τ-s relations are evaluated using a large experimental database of 78 double-lap FRP-steel specimens. To facilitate the evaluation process, a robust finite element (FE) model is developed for each test, implementing data from either of the existing τ-s relations to define the FRP-steel interface. Comparisons between test and FE results indicated that the existing τ-s models were unable of predicting the ultimate load (Pu) and effective bond length (Leff) of FRP-steel joints, or the relation between Pu and bond length and that between Leff and FRP modulus (Ef). A new τ-s model is developed based on an inverse FE simulation, comparison with experimental results, and regression a...
In the last few decades, the concrete industry has been massively expanded with the adoption of v... more In the last few decades, the concrete industry has been massively expanded with the adoption of various kinds of binding materials. As a substitute to cement and in an effort to relieve ecofriendly difficulties linked with cement creation, the utilization of industrial waste as cementitious material can sharply reduce the amount of trash disposed of in lakes and landfills. With respect to the mechanical properties, durability and thermal behavior, ground-granulated blast-furnace slag (GGBS) delineates a rational way to develop sustainable cement and concrete. Apart from environmental benefits, the replacement of cement by GGBS illustrates an adequate way to mitigate the economic impact. Although many researchers concentrate on utilizing GGBS in concrete production, knowledge is scattered, and additional research is needed to better understand relationships among a wide spectrum of key questions and to more accurately determine these preliminary findings. This work aims to shed some ...
IOP Conference Series: Materials Science and Engineering
The Ordinary Portland Cement (OPC) is one of the major ingredient utilized for the manufacture of... more The Ordinary Portland Cement (OPC) is one of the major ingredient utilized for the manufacture of concrete. The manufacturing of cement includes the release of huge amounts of CO2 gas as a main contributor for greenhouse influence and global warming. Several researchers have investigated the characteristics of OPC concrete utilizing cementitious materials like fly ash, silica fume, and Ground Granulated Blast furnace Slag (GGBS) as replacement materials. The article aims to investigate experimentally the flexural behavior of concrete beams with GGBS. The experimental work was divided into three stages, the first one consists of six reinforced concrete beam specimens with (0%, 40% and 60%) of GGBS. During this stage, the used steel bars were 8 mm diameter and 500 mm in length. In the second stage, the length of the steel bars was reduced to 400 mm with the best mixture of (GGBS+OPC) that obtained from stage 1. In the third stage, the best length of steel bars was used with the best (...
The push for sustainability in the construction sector has demanded the use of increasingly renew... more The push for sustainability in the construction sector has demanded the use of increasingly renewable resources. These natural fibers are biodegradable and non-toxic, and their mechanical capabilities are superior to those of synthetic fibers in terms of strength and durability. A lot of research recommends coconut fibers as an alternative to synthetic fibers. However, the knowledge is scattered, and no one can easily judge the suitability of coconut fibers in concrete. This paper presents a summary of research progress on coconut fiber (natural fibers) reinforced concrete. The effects of coconut fibers on the properties of concrete are reviewed. Factors affecting the fresh, hardened, and durability properties of concrete reinforced with coconut fiber are discussed. Results indicate that coconut fiber improved the mechanical performance of concrete due to crack prevention, similar to the synthetic fibers but decreased the flowability of concrete. However, coconut fibers improved fle...
Concrete is a commonly used building material; however, it is subject to abrupt failure and limit... more Concrete is a commonly used building material; however, it is subject to abrupt failure and limited energy absorption when yielding. The use of short discrete fibers has displayed a lot of potential in overcoming these issues. Sisal is a natural fiber that is renewable, inexpensive, and readily accessible. SSF is a potential reinforcement for use in concrete because of its cheap cost, low density, high specific strength and modulus, negligible health risk, easy accessibility in certain states, and renewability. In current centuries, there has been growing importance in discovering new uses for SSF-reinforced concrete, which is normally utilized to make ropes, mats, carpets, and other decorative items. This article gives an overview of current advancements in SSF and composites. The qualities of SSF, the interface between SSF and the matrix, and SSF-reinforced properties such as fresh, mechanical strength, and durability have all been examined. The results show that SSF increased str...
Based on the salp swarm algorithm (SSA), this paper proposes an efficient metaheuristic algorithm... more Based on the salp swarm algorithm (SSA), this paper proposes an efficient metaheuristic algorithm for solving global optimization problems and optimizing two commonly encountered geotechnical engineering structures: reinforced concrete cantilever retaining walls and shallow spread foundations. Two new equations for the leader- and followers-position-updating procedures were introduced in the proposed adaptive salp swarm optimization (ASSA). This change improved the algorithm’s exploration capabilities while preventing it from converging prematurely. Benchmark test functions were used to confirm the proposed algorithm’s performance, and the results were compared to the SSA and other effective optimization algorithms. A Wilcoxon’s rank sum test was performed to evaluate the pairwise statistical performances of the algorithms, and it indicated the significant superiority of the ASSA. The new algorithm can also be used to optimize low-cost retaining walls and foundations. In the analysi...
Plastics have become an essential part of our daily lives, and global plastic production has incr... more Plastics have become an essential part of our daily lives, and global plastic production has increased dramatically in the past 50 years. This has significantly increased the amount of plastic garbage produced. Researchers have recently been interested in using trash and recyclable plastics in concrete as an ecologically acceptable building material. A large number of publications have been published that describe the behavior of concrete, containing waste and recovered plastic com ponents. However, information is scattered, and no one knows how plastic trash behaves as concrete materials. This research examines the use of plastic waste (PW) as aggregate or fiber in cement mortar and concrete manufacturing. The article reviewed the three most significant features of concrete: fresh properties, mechanical strength, and durability. PW and cement connections were also studied using microstructure analysis (scan electronic microscopy). The results showed that PW, as a fiber, enhanced me...
The renewable energy is expanding in the sub-systems of distribution electrical grids, due to hav... more The renewable energy is expanding in the sub-systems of distribution electrical grids, due to having low energy costs and high reliability. In this study, off-grid design of the hybrid energy system based-renewable resources is proposed for a house in Hamadan city in Iran. The resources are designed based on economic and climate data such as battery, solar cells, wind turbines, and electrolyser/fuel cell. The design of mentioned resources is done with attention to twofold optimization modelling including operation cost (OC) and net present cost (NPC). The modelling of resources is implemented in HOMER software based on optimal sizing and installation costs. In the numerical simulation, the three optimal designs are presented to meet electrical demand with minimum costs and high reliability.
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Papers by Ali Majdi