Pub Date : 2024-01-01DOI: 10.28991/cej-2024-010-01-010
Husein A. Alzgool, Ahmad M. Shawashreh, Lujain A. Albtoosh, Basil A. Abusamra
The scarcity of waste in some regions has led to the contemplation of other approaches to providing potable water for human use. In the present research, it is proposed that a portion of the brine wastewater be recycled for potable water purposes through its incorporation into concrete and reinforced concrete compositions. The researchers performed an extensive empirical investigation to examine the impact of incorporating brine wastewater into the concrete mixture on the shear strength, bending stress, and compressive strength of the material. A total of seventy-two beams, each measuring 500 mm in length, 100 mm in width, and 100 mm in depth, were observed. A total of twelve beams were designated as control specimens, while an additional sixty beams were subjected to immersion in brine wastewater at varying concentrations of 2.5, 5, 7.5, 10, and 15%. The beams were reinforced using two longitudinal steel bars with a diameter of 8 millimeters in the tension zone and 6 millimeters in the compression zone. The stirrups included in the study were also measured to have a diameter of 4 mm. The samples were examined at intervals of seven, fourteen, twenty-one, and twenty-eight days. Based on the findings of this study and other relevant studies, it was determined that the use of 10% fresh water as a substitute for brine wastewater yielded the most optimal outcomes. The results obtained after a duration of 28 days indicate a notable increase in both the compressive and bending strengths of the concrete samples, with improvements of around 22% and 2.6% seen in comparison to the reference specimens. The impact of brine wastewater on the corrosion of reinforcing steel in reinforced concrete was investigated. The empirical findings indicated that the introduction of brine wastewater at a concentration of 10% to the concrete constituents did not provide any discernible repercussions over a period of 65 days. Doi: 10.28991/CEJ-2024-010-01-010 Full Text: PDF
{"title":"Experimental investigations: Reinforced Concrete Beams Bending Strength with Brine Wastewater in Short Age","authors":"Husein A. Alzgool, Ahmad M. Shawashreh, Lujain A. Albtoosh, Basil A. Abusamra","doi":"10.28991/cej-2024-010-01-010","DOIUrl":"https://doi.org/10.28991/cej-2024-010-01-010","url":null,"abstract":"The scarcity of waste in some regions has led to the contemplation of other approaches to providing potable water for human use. In the present research, it is proposed that a portion of the brine wastewater be recycled for potable water purposes through its incorporation into concrete and reinforced concrete compositions. The researchers performed an extensive empirical investigation to examine the impact of incorporating brine wastewater into the concrete mixture on the shear strength, bending stress, and compressive strength of the material. A total of seventy-two beams, each measuring 500 mm in length, 100 mm in width, and 100 mm in depth, were observed. A total of twelve beams were designated as control specimens, while an additional sixty beams were subjected to immersion in brine wastewater at varying concentrations of 2.5, 5, 7.5, 10, and 15%. The beams were reinforced using two longitudinal steel bars with a diameter of 8 millimeters in the tension zone and 6 millimeters in the compression zone. The stirrups included in the study were also measured to have a diameter of 4 mm. The samples were examined at intervals of seven, fourteen, twenty-one, and twenty-eight days. Based on the findings of this study and other relevant studies, it was determined that the use of 10% fresh water as a substitute for brine wastewater yielded the most optimal outcomes. The results obtained after a duration of 28 days indicate a notable increase in both the compressive and bending strengths of the concrete samples, with improvements of around 22% and 2.6% seen in comparison to the reference specimens. The impact of brine wastewater on the corrosion of reinforcing steel in reinforced concrete was investigated. The empirical findings indicated that the introduction of brine wastewater at a concentration of 10% to the concrete constituents did not provide any discernible repercussions over a period of 65 days. Doi: 10.28991/CEJ-2024-010-01-010 Full Text: PDF","PeriodicalId":10233,"journal":{"name":"Civil Engineering Journal","volume":"23 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140523860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-01DOI: 10.28991/cej-2024-010-01-019
Ahsan Hussain Khan, S. Naimi
This study aims to explore the impact of construction managers' political skills on the relationship between quality management practices and the success of inter-organizational construction projects in Pakistan. Objectively, it examines how project managers' political acumen influences the effectiveness of quality management strategies and, consequently, project success. Employing a survey-based methodology, the research encompasses a broad spectrum of professionals involved in various construction projects across Pakistan. Through this analysis, the study identifies key challenges to project success and assesses the correlation between managerial political skills and the effective implementation of quality management practices. The findings reveal a notable positive relationship between these elements, highlighting the critical role of skills such as communication, stakeholder management, and conflict resolution. Additionally, the research underscores the interconnected nature of managerial competencies and identifies key factors impacting project success through advanced statistical techniques like principal component analysis and median absolute deviation. Significantly, this research provides novel insights into the role of human factors in the Pakistani construction industry's project management, proposing actionable strategies for skill enhancement and offering a comprehensive overview of factors influencing project success. These findings not only show the current skills and practices landscape but also lay the groundwork for future research and strategy implementation to boost industry-wide success. Doi: 10.28991/CEJ-2024-010-01-019 Full Text: PDF
{"title":"Effect of Construction Manager's Political Skills on Relationship between Quality Management Practices and Inter-Organizational Project Success","authors":"Ahsan Hussain Khan, S. Naimi","doi":"10.28991/cej-2024-010-01-019","DOIUrl":"https://doi.org/10.28991/cej-2024-010-01-019","url":null,"abstract":"This study aims to explore the impact of construction managers' political skills on the relationship between quality management practices and the success of inter-organizational construction projects in Pakistan. Objectively, it examines how project managers' political acumen influences the effectiveness of quality management strategies and, consequently, project success. Employing a survey-based methodology, the research encompasses a broad spectrum of professionals involved in various construction projects across Pakistan. Through this analysis, the study identifies key challenges to project success and assesses the correlation between managerial political skills and the effective implementation of quality management practices. The findings reveal a notable positive relationship between these elements, highlighting the critical role of skills such as communication, stakeholder management, and conflict resolution. Additionally, the research underscores the interconnected nature of managerial competencies and identifies key factors impacting project success through advanced statistical techniques like principal component analysis and median absolute deviation. Significantly, this research provides novel insights into the role of human factors in the Pakistani construction industry's project management, proposing actionable strategies for skill enhancement and offering a comprehensive overview of factors influencing project success. These findings not only show the current skills and practices landscape but also lay the groundwork for future research and strategy implementation to boost industry-wide success. Doi: 10.28991/CEJ-2024-010-01-019 Full Text: PDF","PeriodicalId":10233,"journal":{"name":"Civil Engineering Journal","volume":"16 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140522005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-01DOI: 10.28991/cej-2024-010-01-012
Asser M. Elsheikh, H. H. Alzamili
High temperatures during a fire can significantly degrade the structural capacity of concrete. However, in many cases, it is possible to restore and strengthen fire-damaged concrete rather than completely rebuild damaged structures. The study considered two types of concrete (normal 25 MPa and high-strength 65 MPa) with two types of strengthening techniques: carbon-fiber-reinforced polymers (CFRP) sheets with different thicknesses of 1.5 and 2.5 mm and slurry-infiltrated fibrous concrete (SIFCON) jacketing with different fiber sizes of 20 and 30 mm. The numerical simulations and analyses were conducted to capture the complex behavior of fire-damaged concrete members (beams). A fire-damaged concrete beam subjected to an extreme or critical fire Exposure time (2 hours) was evaluated and modified using a finite element simulation approach. The simulation process included three stages: the first, subjecting the concrete beam to thermal loading; the second, reflecting the fire distribution map to another model of applying mechanical loading; and the third, involving the application of strengthening to the damaged model. The results showed that the strengthening using CFRP with a thickness of 2.5 improved the load-carrying capacity compared with SIFCON in both types of concrete. 200% improvement for the normal-strength concrete beam and a 136% improvement for the high-strength concrete beam, compared to the damaged beams. Doi: 10.28991/CEJ-2024-010-01-012 Full Text: PDF
{"title":"Behavior of Fire-damaged RC Beams After Strengthening with Various Techniques","authors":"Asser M. Elsheikh, H. H. Alzamili","doi":"10.28991/cej-2024-010-01-012","DOIUrl":"https://doi.org/10.28991/cej-2024-010-01-012","url":null,"abstract":"High temperatures during a fire can significantly degrade the structural capacity of concrete. However, in many cases, it is possible to restore and strengthen fire-damaged concrete rather than completely rebuild damaged structures. The study considered two types of concrete (normal 25 MPa and high-strength 65 MPa) with two types of strengthening techniques: carbon-fiber-reinforced polymers (CFRP) sheets with different thicknesses of 1.5 and 2.5 mm and slurry-infiltrated fibrous concrete (SIFCON) jacketing with different fiber sizes of 20 and 30 mm. The numerical simulations and analyses were conducted to capture the complex behavior of fire-damaged concrete members (beams). A fire-damaged concrete beam subjected to an extreme or critical fire Exposure time (2 hours) was evaluated and modified using a finite element simulation approach. The simulation process included three stages: the first, subjecting the concrete beam to thermal loading; the second, reflecting the fire distribution map to another model of applying mechanical loading; and the third, involving the application of strengthening to the damaged model. The results showed that the strengthening using CFRP with a thickness of 2.5 improved the load-carrying capacity compared with SIFCON in both types of concrete. 200% improvement for the normal-strength concrete beam and a 136% improvement for the high-strength concrete beam, compared to the damaged beams. Doi: 10.28991/CEJ-2024-010-01-012 Full Text: PDF","PeriodicalId":10233,"journal":{"name":"Civil Engineering Journal","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140517423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-01DOI: 10.28991/cej-2024-010-01-03
Osamah Alqawas, Md. Rehan Sadique, Zaid Mohammad, Sanan Husain Khan
In the current capital of Yemen, Sana’a, a time-efficient and economical transportation system is one of the greatest challenges to overcome the increasing urbanization for many years. Rapid transport systems use tunnel structures to reach the city's most inaccessible areas. Given the Gulf's geopolitical unrest, these structures could also serve as emergency shelters. Consequently, this research conducted an experimental soil exploration investigation in Sana'a, Yemen, to identify potential tunneling sites for the city's rapid transit system. The field exploration, in-situ, and laboratory soil testing at the four locations were performed with the collaboration of the Ministry of Public Works & Highways, Yemen. Further, to calculate the geotechnical parameters for tunnel design, numerical analysis has been carried out using the finite element package ABAQUS, and two-dimensional plane-strain numerical models of underground tunnel structure have been developed to conduct the parametric study in different soil types and boundary conditions under static loading. The material behavior of soil strata has been incorporated into the well-known Mohr-Coulomb constitutive model. The field investigation found that the geotechnical properties of the soil strata in Sana’a have a lot of variation. The numerical study shows that the maximum deformation in the concrete liner of the tunnel was observed at the crown of the tunnel. The ovalling effect in tunnel concrete liner was also seen in all the tunnel models, and the maximum ground settlement at sites 1, 2, 3, and 4 was estimated to be approximately 4, 25, 17, and 11 mm, respectively. Doi: 10.28991/CEJ-2024-010-01-03 Full Text: PDF
{"title":"Experimental and Numerical Study of Soil Strata for Underground Transportation System: A Case Study","authors":"Osamah Alqawas, Md. Rehan Sadique, Zaid Mohammad, Sanan Husain Khan","doi":"10.28991/cej-2024-010-01-03","DOIUrl":"https://doi.org/10.28991/cej-2024-010-01-03","url":null,"abstract":"In the current capital of Yemen, Sana’a, a time-efficient and economical transportation system is one of the greatest challenges to overcome the increasing urbanization for many years. Rapid transport systems use tunnel structures to reach the city's most inaccessible areas. Given the Gulf's geopolitical unrest, these structures could also serve as emergency shelters. Consequently, this research conducted an experimental soil exploration investigation in Sana'a, Yemen, to identify potential tunneling sites for the city's rapid transit system. The field exploration, in-situ, and laboratory soil testing at the four locations were performed with the collaboration of the Ministry of Public Works & Highways, Yemen. Further, to calculate the geotechnical parameters for tunnel design, numerical analysis has been carried out using the finite element package ABAQUS, and two-dimensional plane-strain numerical models of underground tunnel structure have been developed to conduct the parametric study in different soil types and boundary conditions under static loading. The material behavior of soil strata has been incorporated into the well-known Mohr-Coulomb constitutive model. The field investigation found that the geotechnical properties of the soil strata in Sana’a have a lot of variation. The numerical study shows that the maximum deformation in the concrete liner of the tunnel was observed at the crown of the tunnel. The ovalling effect in tunnel concrete liner was also seen in all the tunnel models, and the maximum ground settlement at sites 1, 2, 3, and 4 was estimated to be approximately 4, 25, 17, and 11 mm, respectively. Doi: 10.28991/CEJ-2024-010-01-03 Full Text: PDF","PeriodicalId":10233,"journal":{"name":"Civil Engineering Journal","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140516532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-01DOI: 10.28991/cej-2024-010-01-017
A. S. Al-Gharbawi, Ahmed M. Najemalden, Mohammed Y. Fattah
Expansive soil is a form of soil that can expand and contract, changing its volume. Montmorillonite, a mineral with the ability to dissolve in water, makes up the majority of these kinds of soils, and by increasing the volume of the soil, it causes the soil to heave. Expansive soils could be a substantial concern for engineered buildings due to their capacity to adjust to seasonal variations by contracting or expanding moisture content. Many researchers focused on soils that were swollen and looked at how they behaved as well as how they could be improved. In this study, the work depends on inserting micro-piles with different depths and configuration widths to investigate which depth and configuration can be obtained to improve the bearing capacity of foundations on expansive soil. The main purpose of this study is to reinforce the expansive soil with micro-piles with different depths (1B, 2B, and 3B) and different configuration widths (under footing only, 1B and 2B). It was concluded that the soil reinforced with micro-piles improved the load-bearing capacity of the expensive soil and decreased the swell pressure. The increasing depth of the micropiles 2B to 3B (B is the width/diameter of the foundation) can increase the bearing capacity by just 6%; therefore, increasing the depth beyond 2B is not beneficial. Also, the increase in width of the configuration of the micro piles from 1B to 2B increases the bearing capacity by just 4%; therefore, the increase in width greater than 1B is not valid. Doi: 10.28991/CEJ-2024-010-01-017 Full Text: PDF
{"title":"Studying the Behavior of Expansive Soil Reinforced by Micropiles","authors":"A. S. Al-Gharbawi, Ahmed M. Najemalden, Mohammed Y. Fattah","doi":"10.28991/cej-2024-010-01-017","DOIUrl":"https://doi.org/10.28991/cej-2024-010-01-017","url":null,"abstract":"Expansive soil is a form of soil that can expand and contract, changing its volume. Montmorillonite, a mineral with the ability to dissolve in water, makes up the majority of these kinds of soils, and by increasing the volume of the soil, it causes the soil to heave. Expansive soils could be a substantial concern for engineered buildings due to their capacity to adjust to seasonal variations by contracting or expanding moisture content. Many researchers focused on soils that were swollen and looked at how they behaved as well as how they could be improved. In this study, the work depends on inserting micro-piles with different depths and configuration widths to investigate which depth and configuration can be obtained to improve the bearing capacity of foundations on expansive soil. The main purpose of this study is to reinforce the expansive soil with micro-piles with different depths (1B, 2B, and 3B) and different configuration widths (under footing only, 1B and 2B). It was concluded that the soil reinforced with micro-piles improved the load-bearing capacity of the expensive soil and decreased the swell pressure. The increasing depth of the micropiles 2B to 3B (B is the width/diameter of the foundation) can increase the bearing capacity by just 6%; therefore, increasing the depth beyond 2B is not beneficial. Also, the increase in width of the configuration of the micro piles from 1B to 2B increases the bearing capacity by just 4%; therefore, the increase in width greater than 1B is not valid. Doi: 10.28991/CEJ-2024-010-01-017 Full Text: PDF","PeriodicalId":10233,"journal":{"name":"Civil Engineering Journal","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140526328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-25DOI: 10.28991/cej-sp2023-09-014
Medhat Abdelrahman Youssef, Ahmed H. Ibrahim, Ramy A. Bakry
This study presents the dark side of "unethical practices" in construction projects in Egypt, which impact the construction industry's development. It also identifies the project parties' unethical practices in funded projects and the Technical Audit's role in fighting them. A mixed methodology was used for collecting and analyzing quantitative and qualitative data. The study results indicated the owner's and bidder's unethical practices were Disclaim liability for nominated subcontractor mistakes and submitting an unbalanced bid, respectively. Also, the procedure militating against the practices was adopting and applying the technical audit concept to governmental projects. Separate analyses revealed differing viewpoints among consultants, owners, and contractors. The study contributes to the creation of honest competition to develop the construction industry, reducing public money losses, and evaluating competitors on a stable and sound basis. Also, building awareness and sensitizing our community to the construction project's dark side is necessary for getting a legally sustainable solution in future tender law formulation. Doi: 10.28991/CEJ-SP2023-09-014 Full Text: PDF
本研究介绍了埃及建筑项目中 "不道德行为 "的阴暗面，这些行为影响了建筑业的发展。研究还指出了项目方在资助项目中的不道德行为，以及技术审计在打击不道德行为中的作用。研究采用混合方法收集和分析定量和定性数据。研究结果表明，业主和投标人的不道德行为分别是对提名分包商的错误免责和提交不平衡的投标书。此外，不利于这些做法的程序是在政府项目中采用和应用技术审计概念。分别进行的分析表明，顾问、业主和承包商的观点各不相同。本研究有助于为发展建筑业创造诚实竞争的环境，减少公共资金损失，并在稳定和健全的基础上评估竞争对手。同时，在今后的招标法制定过程中，有必要树立社会意识，提高对建筑项目阴暗面的敏感度，以获得法律上可持续的解决方案。Doi: 10.28991/CEJ-SP2023-09-014 Full Text：PDF
{"title":"Technical Audit and Unethical Practices in the Construction Industry","authors":"Medhat Abdelrahman Youssef, Ahmed H. Ibrahim, Ramy A. Bakry","doi":"10.28991/cej-sp2023-09-014","DOIUrl":"https://doi.org/10.28991/cej-sp2023-09-014","url":null,"abstract":"This study presents the dark side of \"unethical practices\" in construction projects in Egypt, which impact the construction industry's development. It also identifies the project parties' unethical practices in funded projects and the Technical Audit's role in fighting them. A mixed methodology was used for collecting and analyzing quantitative and qualitative data. The study results indicated the owner's and bidder's unethical practices were Disclaim liability for nominated subcontractor mistakes and submitting an unbalanced bid, respectively. Also, the procedure militating against the practices was adopting and applying the technical audit concept to governmental projects. Separate analyses revealed differing viewpoints among consultants, owners, and contractors. The study contributes to the creation of honest competition to develop the construction industry, reducing public money losses, and evaluating competitors on a stable and sound basis. Also, building awareness and sensitizing our community to the construction project's dark side is necessary for getting a legally sustainable solution in future tender law formulation. Doi: 10.28991/CEJ-SP2023-09-014 Full Text: PDF","PeriodicalId":10233,"journal":{"name":"Civil Engineering Journal","volume":"48 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139236282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-25DOI: 10.28991/cej-sp2023-09-013
H. Putra, Alfaris B. Arrazzaq, Raihan M. I. Hidayatullah, Maulina Lamuse, F. R. Ananda, Angga Prayoga
Expansive soil is problematic from an infrastructural perspective, including the subgrade of pavement construction. The high swelling and shrinkage of this soil promotes subgrade imbalance, resulting in severe pavement construction problems. One potential soil improvement method is the carbonate precipitation method; however, this method requires a catalyst. This research aims to evaluate the use of tofu waste as a biocatalyst in the carbonate precipitation method to improve expansive soil. Several variations of tofu waste reacted with reagents (urea and calcium chloride) as treatment solutions. Soil identification, hydrolysis, precipitation, Atterberg limits, California bearing ratio (CBR), scanning electron microscopy (SEM), and X-ray diffraction (XRD) tests were performed. The results showed that the optimum tofu waste concentration was 40 g/L. The swelling ratio in the soil treated with carbonate decreased by 12.5%. The CBR value of the treated soil also increased by 23.9%. The SEM and XRD analysis results showed the formation of aragonite, calcite, and vaterite. Moreover, this study confirmed that tofu waste is a promising biocatalyst for carbonate precipitation. Doi: 10.28991/CEJ-SP2023-09-013 Full Text: PDF
从基础设施的角度来看，膨胀性土壤是一个问题，包括路面施工的路基。这种土壤的高膨胀性和高收缩性会导致路基失衡，造成严重的路面施工问题。一种潜在的土壤改良方法是碳酸盐沉淀法，但这种方法需要催化剂。本研究旨在评估在碳酸盐沉淀法中使用豆腐渣作为生物催化剂来改良膨胀性土壤的情况。几种不同的豆腐废料与试剂（尿素和氯化钙）反应，作为处理溶液。研究人员进行了土壤鉴定、水解、沉淀、阿特伯格极限、加州承载比（CBR）、扫描电子显微镜（SEM）和 X 射线衍射（XRD）测试。结果表明，豆腐渣的最佳浓度为 40 克/升。用碳酸盐处理过的土壤的膨胀率降低了 12.5%。经处理土壤的 CBR 值也提高了 23.9%。扫描电镜和 XRD 分析结果表明，土壤中形成了文石、方解石和辉绿岩。此外，该研究还证实豆腐渣是一种很有前景的碳酸盐沉淀生物催化剂。Doi: 10.28991/CEJ-SP2023-09-013 Full Text：PDF
{"title":"Improving CBR Parameter of Expansive Soil Using the Carbonate Precipitation Method with Tofu Waste as a Biocatalyst","authors":"H. Putra, Alfaris B. Arrazzaq, Raihan M. I. Hidayatullah, Maulina Lamuse, F. R. Ananda, Angga Prayoga","doi":"10.28991/cej-sp2023-09-013","DOIUrl":"https://doi.org/10.28991/cej-sp2023-09-013","url":null,"abstract":"Expansive soil is problematic from an infrastructural perspective, including the subgrade of pavement construction. The high swelling and shrinkage of this soil promotes subgrade imbalance, resulting in severe pavement construction problems. One potential soil improvement method is the carbonate precipitation method; however, this method requires a catalyst. This research aims to evaluate the use of tofu waste as a biocatalyst in the carbonate precipitation method to improve expansive soil. Several variations of tofu waste reacted with reagents (urea and calcium chloride) as treatment solutions. Soil identification, hydrolysis, precipitation, Atterberg limits, California bearing ratio (CBR), scanning electron microscopy (SEM), and X-ray diffraction (XRD) tests were performed. The results showed that the optimum tofu waste concentration was 40 g/L. The swelling ratio in the soil treated with carbonate decreased by 12.5%. The CBR value of the treated soil also increased by 23.9%. The SEM and XRD analysis results showed the formation of aragonite, calcite, and vaterite. Moreover, this study confirmed that tofu waste is a promising biocatalyst for carbonate precipitation. Doi: 10.28991/CEJ-SP2023-09-013 Full Text: PDF","PeriodicalId":10233,"journal":{"name":"Civil Engineering Journal","volume":"292 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139236334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-01DOI: 10.28991/cej-2023-09-11-03
Riana H. Lumingkewas, S. Hadiwardoyo, F. A. Hadiwardoyo
This research aims to evaluate the block method against the cube test method using variations in thickness. Paving blocks can be produced using a hydraulic machine or a simple press, and their performance can be measured based on density and compressive strength tests. The block test method shows that with the same material composition forming the paving block, a paving block with a higher thickness can lead to a lower compressive strength value. In contrast, the cube test method shows different results. The paving blocks used in this study had width and length sizes of 100 and 200 mm, respectively, and had varying heights of 60, 80, and 100 mm. The results reveal that the compressive strength of concrete paving blocks is more precise based on density. Furthermore, the empirical equation and conversion coefficient of the compressive strength of the block test to the cube test have been obtained. This empirical equation is highly recommended for the road pavement industry in controlling the quality of compressive strength, even when using block tests. Further research can help develop a formula for using additive materials in paving blocks. Doi: 10.28991/CEJ-2023-09-11-03 Full Text: PDF
{"title":"Laboratory Innovation to Investigate Concrete Paving Blocks Compressive Strength","authors":"Riana H. Lumingkewas, S. Hadiwardoyo, F. A. Hadiwardoyo","doi":"10.28991/cej-2023-09-11-03","DOIUrl":"https://doi.org/10.28991/cej-2023-09-11-03","url":null,"abstract":"This research aims to evaluate the block method against the cube test method using variations in thickness. Paving blocks can be produced using a hydraulic machine or a simple press, and their performance can be measured based on density and compressive strength tests. The block test method shows that with the same material composition forming the paving block, a paving block with a higher thickness can lead to a lower compressive strength value. In contrast, the cube test method shows different results. The paving blocks used in this study had width and length sizes of 100 and 200 mm, respectively, and had varying heights of 60, 80, and 100 mm. The results reveal that the compressive strength of concrete paving blocks is more precise based on density. Furthermore, the empirical equation and conversion coefficient of the compressive strength of the block test to the cube test have been obtained. This empirical equation is highly recommended for the road pavement industry in controlling the quality of compressive strength, even when using block tests. Further research can help develop a formula for using additive materials in paving blocks. Doi: 10.28991/CEJ-2023-09-11-03 Full Text: PDF","PeriodicalId":10233,"journal":{"name":"Civil Engineering Journal","volume":"317 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139297840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-01DOI: 10.28991/cej-2023-09-11-02
M. Benzerzour, Duc Chinh Chu, Mouhamadou Amar, J. Kleib, N. Abriak, J. Nadah
The objectives of this study were to find out in detail how well granulated blast furnace slag (GBFS) could be replaced by flash-calcined sediment (SF sediment) in terms of hydration kinetics and mechanical-microstructural properties when developing an eco-friendly cement binder. The results indicated that the SF sediment substitution with a rate of 25% wt significantly improved the hydration kinetics of cement compared to the reference. This contributed to a considerable enhancement of the mechanical-microstructural properties of the mortar containing the SF sediment. By comparison with the reference, the strength of multi-composite cement-based mortar increased by 33% at 2 days and by 4.5% at 28 days, whereas its porosity decreased by 16.32% and by 12.44% for the same period. The SEM-EDS result showed that the SF sediment substitution did not significantly modify the chemical composition of the C-S-H phase, with a Ca/Si ratio range of 1.82 to 2.84 for both cement pastes. Moreover, Mg2+ and Al3+ions were two principal elements incorporated in C-S-H gels, with different ratios depending on the Ca/Si ratio of C-S-H gels. A novel model established from a combination of the curve fitting method and Power’s approach allowed for accurate prediction of the strength development of multi-composite cement-based mortars. Overall, the SF sediment substitution could be considered a promising option to develop a more eco-friendly cement binder, while the novel approach could be used as a reliable model for the strength prediction of blended cement. Doi: 10.28991/CEJ-2023-09-11-02 Full Text: PDF
{"title":"Efficient Multi-Composite Cement Made of Granulated Blast Furnace Slag (GBFS) and Flash-calcined Sediment","authors":"M. Benzerzour, Duc Chinh Chu, Mouhamadou Amar, J. Kleib, N. Abriak, J. Nadah","doi":"10.28991/cej-2023-09-11-02","DOIUrl":"https://doi.org/10.28991/cej-2023-09-11-02","url":null,"abstract":"The objectives of this study were to find out in detail how well granulated blast furnace slag (GBFS) could be replaced by flash-calcined sediment (SF sediment) in terms of hydration kinetics and mechanical-microstructural properties when developing an eco-friendly cement binder. The results indicated that the SF sediment substitution with a rate of 25% wt significantly improved the hydration kinetics of cement compared to the reference. This contributed to a considerable enhancement of the mechanical-microstructural properties of the mortar containing the SF sediment. By comparison with the reference, the strength of multi-composite cement-based mortar increased by 33% at 2 days and by 4.5% at 28 days, whereas its porosity decreased by 16.32% and by 12.44% for the same period. The SEM-EDS result showed that the SF sediment substitution did not significantly modify the chemical composition of the C-S-H phase, with a Ca/Si ratio range of 1.82 to 2.84 for both cement pastes. Moreover, Mg2+ and Al3+ions were two principal elements incorporated in C-S-H gels, with different ratios depending on the Ca/Si ratio of C-S-H gels. A novel model established from a combination of the curve fitting method and Power’s approach allowed for accurate prediction of the strength development of multi-composite cement-based mortars. Overall, the SF sediment substitution could be considered a promising option to develop a more eco-friendly cement binder, while the novel approach could be used as a reliable model for the strength prediction of blended cement. Doi: 10.28991/CEJ-2023-09-11-02 Full Text: PDF","PeriodicalId":10233,"journal":{"name":"Civil Engineering Journal","volume":"178 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139300023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-01DOI: 10.28991/cej-2023-09-11-08
Krittiya Pawanithiboworn, T. Pannachet, M. Boonpichetvong
This study aims to understand the behavior of connection, which holds an important key to efficient designs of the cold-formed steel structure. The focus is on examining parameters that affect the rotational stiffness and behavior of the cold-formed steel connection made of single-lipped channel sections with a bolt and gusset plate system. The numerical study has been conducted using component-based finite element analysis, with the studied parameters including bolt diameters, number of bolts in the group, size of the bolt group, thickness of the cold-formed steel cross-section, and thickness of the connecting plate. The effect of the variables is evaluated and explained by comparison. The result of the study reveals that the rotational behavior of the connection depends on the details of the assembly. For the given base connection, the parameters that give the greatest effect on the rotation stiffness and the moment capacity are the number of bolts and the bolt diameters, whereas the parameter that provides the least effect is the bolt spacing. On the other hand, the bolt group size is the most influential parameter for the member connection. For both types of connections, the thickness of the cold-formed steel section and the thickness of the gusset plate have shown limited effect on stiffness and strength. Using different variables in assembling the connection can also lead to different failure types, either bolt failure or excessive bolt hole deformation, which leads to plate failure. Doi: 10.28991/CEJ-2023-09-11-08 Full Text: PDF
{"title":"Investigation of Parameters Affecting Rotational Behavior of Cold-Formed Steel Connection","authors":"Krittiya Pawanithiboworn, T. Pannachet, M. Boonpichetvong","doi":"10.28991/cej-2023-09-11-08","DOIUrl":"https://doi.org/10.28991/cej-2023-09-11-08","url":null,"abstract":"This study aims to understand the behavior of connection, which holds an important key to efficient designs of the cold-formed steel structure. The focus is on examining parameters that affect the rotational stiffness and behavior of the cold-formed steel connection made of single-lipped channel sections with a bolt and gusset plate system. The numerical study has been conducted using component-based finite element analysis, with the studied parameters including bolt diameters, number of bolts in the group, size of the bolt group, thickness of the cold-formed steel cross-section, and thickness of the connecting plate. The effect of the variables is evaluated and explained by comparison. The result of the study reveals that the rotational behavior of the connection depends on the details of the assembly. For the given base connection, the parameters that give the greatest effect on the rotation stiffness and the moment capacity are the number of bolts and the bolt diameters, whereas the parameter that provides the least effect is the bolt spacing. On the other hand, the bolt group size is the most influential parameter for the member connection. For both types of connections, the thickness of the cold-formed steel section and the thickness of the gusset plate have shown limited effect on stiffness and strength. Using different variables in assembling the connection can also lead to different failure types, either bolt failure or excessive bolt hole deformation, which leads to plate failure. Doi: 10.28991/CEJ-2023-09-11-08 Full Text: PDF","PeriodicalId":10233,"journal":{"name":"Civil Engineering Journal","volume":"53 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139292692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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