S. Mahadik, S. Bhagat, P. D. Gunaware, Vijay N. Patil
A shear wall becomes weak when an opening is provided in it. It is important to provide some arrangement in the shear wall having an opening for recovering strength loss due to the opening. It may be recovered by providing some steel profiles around the opening or at weaker sections in the shear wall having an opening. At first, the identification of weaker sections in the shear wall having an opening is important and then, the wall can be made stronger as the shear wall without an opening by strengthening weaker sections. In the present study, the performance of a shear wall having an opening subjected to horizontal cyclic loading along the plane of the shear wall in the presence of concealed stiffeners is investigated. The reduced models of shear walls with openings were tested under axial and lateral load conditions. Load-carrying capacity, deformation behavior and strain behavior of shear walls were studied with experiments and the validation of the results was made with general-purpose finite element software ANSYS. Significant improvements were observed in strength, deformation and strain behavior of a shear wall having a central opening using concealed reinforced concrete (RC) stiffeners and steel tube stiffeners. KEYWORDS: Shear wall, Strength, Stiffness, Strain, Openings, Stiffeners.
{"title":"Experimental and Numerical Study of the Behavior of RC Shear Wall with Opening Using Concealed Stiffeners","authors":"S. Mahadik, S. Bhagat, P. D. Gunaware, Vijay N. Patil","doi":"10.14525/jjce.v17i2.04","DOIUrl":"https://doi.org/10.14525/jjce.v17i2.04","url":null,"abstract":"A shear wall becomes weak when an opening is provided in it. It is important to provide some arrangement in the shear wall having an opening for recovering strength loss due to the opening. It may be recovered by providing some steel profiles around the opening or at weaker sections in the shear wall having an opening. At first, the identification of weaker sections in the shear wall having an opening is important and then, the wall can be made stronger as the shear wall without an opening by strengthening weaker sections. In the present study, the performance of a shear wall having an opening subjected to horizontal cyclic loading along the plane of the shear wall in the presence of concealed stiffeners is investigated. The reduced models of shear walls with openings were tested under axial and lateral load conditions. Load-carrying capacity, deformation behavior and strain behavior of shear walls were studied with experiments and the validation of the results was made with general-purpose finite element software ANSYS. Significant improvements were observed in strength, deformation and strain behavior of a shear wall having a central opening using concealed reinforced concrete (RC) stiffeners and steel tube stiffeners. KEYWORDS: Shear wall, Strength, Stiffness, Strain, Openings, Stiffeners.","PeriodicalId":51814,"journal":{"name":"Jordan Journal of Civil Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41572692","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}
Time-cost trade-off is an important optimization problem for contractors, because its optimum solution minimizes the total project cost. Formation of the time-cost trade-off problem causes an important workload, since the problem requires preparation of different construction cost and duration alternatives of the activities. Previous studies focused on the optimum solution of the problem and ignored the difficulties of the preparation of the different construction alternatives for the activities, which is a very difficult task for contractors. In this study, the creation of construction alternatives consisting of different time and cost values is automated. Quantity take-off of construction items is computed by user-defined dimensions of structural elements. Workmanship and material requirements are computed by pre-defined job descriptions and quantity take-off values. Different construction alternatives are formed by assigning different crew sizes and the corresponding construction durations are computed by estimating the job efficiency of the crew by regression models derived from the literature. Precedence relationships of the main construction items are pre-defined and the construction schedule is formed by a line of balance in terms of work days. The problem is optimized by a genetic algorithm the parameters of which are fine-tuned by experimental design. The developed approach is implemented on a spreadsheet application and the total optimization process including data entry is completed in one and a half hour on a desktop computer with i5 CPU. This study contributes to relevant literature by proposing a systematic approach for the formation of construction alternatives of the time-cost trade-off problem. The proposed approach can be beneficial for contractors and project managers to form and solve the time-cost trade-off problem with minimum endeavor and cost. KEYWORDS: Time-cost trade-off, Genetic algorithm, Line of balance, Optimization, Experimental design.
{"title":"Simplified Solution of Time-Cost Trade-off Problem for Building Constructions by Linear Scheduling","authors":"Ö. Bettemir","doi":"10.14525/jjce.v17i2.10","DOIUrl":"https://doi.org/10.14525/jjce.v17i2.10","url":null,"abstract":"Time-cost trade-off is an important optimization problem for contractors, because its optimum solution minimizes the total project cost. Formation of the time-cost trade-off problem causes an important workload, since the problem requires preparation of different construction cost and duration alternatives of the activities. Previous studies focused on the optimum solution of the problem and ignored the difficulties of the preparation of the different construction alternatives for the activities, which is a very difficult task for contractors. In this study, the creation of construction alternatives consisting of different time and cost values is automated. Quantity take-off of construction items is computed by user-defined dimensions of structural elements. Workmanship and material requirements are computed by pre-defined job descriptions and quantity take-off values. Different construction alternatives are formed by assigning different crew sizes and the corresponding construction durations are computed by estimating the job efficiency of the crew by regression models derived from the literature. Precedence relationships of the main construction items are pre-defined and the construction schedule is formed by a line of balance in terms of work days. The problem is optimized by a genetic algorithm the parameters of which are fine-tuned by experimental design. The developed approach is implemented on a spreadsheet application and the total optimization process including data entry is completed in one and a half hour on a desktop computer with i5 CPU. This study contributes to relevant literature by proposing a systematic approach for the formation of construction alternatives of the time-cost trade-off problem. The proposed approach can be beneficial for contractors and project managers to form and solve the time-cost trade-off problem with minimum endeavor and cost. KEYWORDS: Time-cost trade-off, Genetic algorithm, Line of balance, Optimization, Experimental design.","PeriodicalId":51814,"journal":{"name":"Jordan Journal of Civil Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41371604","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}
Utilization of rubber-sand mixtures as construction materials, such as lightweight filling materials, embankment construction, seismic isolation materials, … etc., provides significant advantages, as scrap tires induce environmental issues. In this study, unconsolidated undrained triaxial tests were performed to examine the shear-strength characteristics of geogrid-reinforced sand-rubber mixtures. The rubber percent (10%, 20%, 30%, 40%, 50% and 60%), the confining pressure of the cell (19.6 kPa, 49 kPa and 98 kPa) and the number of geogrid reinforcements (1 to 4) were varied for investigating the impact of these parameters. The relative density of sand remained constant (80%) during the test. The test results were evaluated in terms of the stress-strain characteristics of rubber-sand mixtures. The test findings demonstrated that by increasing the confining pressure of the cell, the same rubber-sand mixtures with the same relative density and rubber content take more loads. The peak stress of unreinforced rubber-sand mixtures increased with the increasing proportion of rubber content up to 30%, beyond which it decreased as rubber content increased. Maximum peak stress and axial strain have been achieved with 50% of the rubber content and four layers of geogrid reinforcement. The brittleness index of the rubber-sand mixture reduces when geogrid reinforcement is added. The minimum brittleness was found to be 0.042 at 50% rubber content with three layers of geogrid reinforcement. KEYWORDS: Geogrid, Shear strength, Triaxial test, Rubber-sand mixture, Soil reinforcement.
{"title":"Effect of Geogrid Reinforcement on Shear Strength Characteristics of a Rubber-Sand Mixture under Undrained Triaxial Test","authors":"Md Asfaque Ansari, L. B. Roy","doi":"10.14525/jjce.v17i2.01","DOIUrl":"https://doi.org/10.14525/jjce.v17i2.01","url":null,"abstract":"Utilization of rubber-sand mixtures as construction materials, such as lightweight filling materials, embankment construction, seismic isolation materials, … etc., provides significant advantages, as scrap tires induce environmental issues. In this study, unconsolidated undrained triaxial tests were performed to examine the shear-strength characteristics of geogrid-reinforced sand-rubber mixtures. The rubber percent (10%, 20%, 30%, 40%, 50% and 60%), the confining pressure of the cell (19.6 kPa, 49 kPa and 98 kPa) and the number of geogrid reinforcements (1 to 4) were varied for investigating the impact of these parameters. The relative density of sand remained constant (80%) during the test. The test results were evaluated in terms of the stress-strain characteristics of rubber-sand mixtures. The test findings demonstrated that by increasing the confining pressure of the cell, the same rubber-sand mixtures with the same relative density and rubber content take more loads. The peak stress of unreinforced rubber-sand mixtures increased with the increasing proportion of rubber content up to 30%, beyond which it decreased as rubber content increased. Maximum peak stress and axial strain have been achieved with 50% of the rubber content and four layers of geogrid reinforcement. The brittleness index of the rubber-sand mixture reduces when geogrid reinforcement is added. The minimum brittleness was found to be 0.042 at 50% rubber content with three layers of geogrid reinforcement. KEYWORDS: Geogrid, Shear strength, Triaxial test, Rubber-sand mixture, Soil reinforcement.","PeriodicalId":51814,"journal":{"name":"Jordan Journal of Civil Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48270442","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}
Disposal or incineration of waste low-density polyethylene (LDPE) bags is a major problem, as it causes pollution. The pavement over time gets deteriorated by vehicular traffic, which mostly results in rutting and other distresses. This research is based on the performance evaluation of hot mix asphalt (HMA) modified with LDPE. Aggregates National Highway Authority Pakistan (NHA) gradation B, bitumen grade 60/70 and waste LDPE bags from the dump yards of Islamabad (Pakistan) were used in this study. Penetration, ductility and softening-point tests were conducted with bitumen modified with different contents of waste LDPE bag flakes; i.e., 0%, 2%, 4%, 6% and 8% to figure out the optimum modifier content (OMC). Marshall testing was performed for the determination of optimum bitumen content (OBC). Using OBC and incorporating LDPE contents as a replacement for OBC, HMA samples were tested for performance evaluation, including rutting resistance and moisture susceptibility and compared with the performance of unmodified HMA. It was observed that 4% of LDPE as a replacement for OBC in the HMA can be used as OMC and yielded better performance results than unmodified asphalt mix. Rutting resistance was improved by 20.86% and tensile strength ratio (TSR) for moisture susceptibility evaluation was above the specified limit of 80%. KEYWORDS: Waste LDPE bags, Low-cost bitumen modifier, Performance evaluation, Performance improvement, Cost comparison, Sustainable environment.
{"title":"Effect of Adding LDPE Bags on Rutting and Stripping Behaviour of Asphalt Mix","authors":"S. Khan, Hamza Marjan","doi":"10.14525/jjce.v17i2.12","DOIUrl":"https://doi.org/10.14525/jjce.v17i2.12","url":null,"abstract":"Disposal or incineration of waste low-density polyethylene (LDPE) bags is a major problem, as it causes pollution. The pavement over time gets deteriorated by vehicular traffic, which mostly results in rutting and other distresses. This research is based on the performance evaluation of hot mix asphalt (HMA) modified with LDPE. Aggregates National Highway Authority Pakistan (NHA) gradation B, bitumen grade 60/70 and waste LDPE bags from the dump yards of Islamabad (Pakistan) were used in this study. Penetration, ductility and softening-point tests were conducted with bitumen modified with different contents of waste LDPE bag flakes; i.e., 0%, 2%, 4%, 6% and 8% to figure out the optimum modifier content (OMC). Marshall testing was performed for the determination of optimum bitumen content (OBC). Using OBC and incorporating LDPE contents as a replacement for OBC, HMA samples were tested for performance evaluation, including rutting resistance and moisture susceptibility and compared with the performance of unmodified HMA. It was observed that 4% of LDPE as a replacement for OBC in the HMA can be used as OMC and yielded better performance results than unmodified asphalt mix. Rutting resistance was improved by 20.86% and tensile strength ratio (TSR) for moisture susceptibility evaluation was above the specified limit of 80%. KEYWORDS: Waste LDPE bags, Low-cost bitumen modifier, Performance evaluation, Performance improvement, Cost comparison, Sustainable environment.","PeriodicalId":51814,"journal":{"name":"Jordan Journal of Civil Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46179148","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}
The aim of this paper is to present a simple method of construction of the load-transfer P-Y curves for the design of laterally loaded piles in sand based on the cone penetration test (CPT). The proposed method was developed on the basis of interpretation of 5 field tests on single instrumented piles conducted in sandy sites in France and shows a simple relationship linking the P-Y curve parameters, the cone penetration resistance and the lateral pile/soil stiffness ratio. The validation process was carried out by direct comparison of the predicted load-deflection curves based on the proposed method to those obtained from a worldwide case history of field lateral loading tests on piles and showed a very good quality of the prediction using the proposed method. KEYWORDS: Piles, Lateral load, Sand, Full-scale loading, P-Y curves, CPT test.
{"title":"Design of Laterally Loaded Single Piles by Using P-Y Curves and the Cone Penetration Test (CPT) in Sandy Soils","authors":"Ali Bouafia","doi":"10.14525/jjce.v17i2.05","DOIUrl":"https://doi.org/10.14525/jjce.v17i2.05","url":null,"abstract":"The aim of this paper is to present a simple method of construction of the load-transfer P-Y curves for the design of laterally loaded piles in sand based on the cone penetration test (CPT). The proposed method was developed on the basis of interpretation of 5 field tests on single instrumented piles conducted in sandy sites in France and shows a simple relationship linking the P-Y curve parameters, the cone penetration resistance and the lateral pile/soil stiffness ratio. The validation process was carried out by direct comparison of the predicted load-deflection curves based on the proposed method to those obtained from a worldwide case history of field lateral loading tests on piles and showed a very good quality of the prediction using the proposed method. KEYWORDS: Piles, Lateral load, Sand, Full-scale loading, P-Y curves, CPT test.","PeriodicalId":51814,"journal":{"name":"Jordan Journal of Civil Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42956543","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}
Fee escalation in construction refers to a boom in the price of an item inside the preliminary agreement or the bottom cost of an undertaking. racking production mission fees must be an ongoing procedure that must always be carried out on all projects, because the reasons for which the price will increase vary from project to project and due to the construction segment. The motive of this observation was to assess fee escalation, escalation factors and mitigation mechanisms in deciding on construction initiatives. From February 1 to 30, 2020, a questionnaire was administered to twelve workers and interviews with seven key informants were conducted for an in-depth look at four selected Jimma University construction projects, which were project A to project D. Relative importance index values were generated and ranked for the elements affecting fee escalation to see their relative significance. It was found that there has been a moderate degree of charge increase within the initiatives studied, from 12% to 21%. The mitigation modalities observed with the aid of the projects, particularly inserting escalation clauses in contractual agreements, making changes requiring funding and increasing time limits, seem to be inadequate, as they do not provide a foundation for choices and remedy of disputes instead of mitigating the escalation of tasks starting from 3.21% to 12%. KEYWORDS: Escalation, Mitigation, Price, Construction projects.
{"title":"Investigation of Price Escalation and Its Mitigation Mechanisms on Selected Building Construction Projects of Jimma University","authors":"Hamelmal Mekonen, Alemu Mosisa Legesse, Frikot Mulatu Ameya","doi":"10.14525/jjce.v17i2.03","DOIUrl":"https://doi.org/10.14525/jjce.v17i2.03","url":null,"abstract":"Fee escalation in construction refers to a boom in the price of an item inside the preliminary agreement or the bottom cost of an undertaking. racking production mission fees must be an ongoing procedure that must always be carried out on all projects, because the reasons for which the price will increase vary from project to project and due to the construction segment. The motive of this observation was to assess fee escalation, escalation factors and mitigation mechanisms in deciding on construction initiatives. From February 1 to 30, 2020, a questionnaire was administered to twelve workers and interviews with seven key informants were conducted for an in-depth look at four selected Jimma University construction projects, which were project A to project D. Relative importance index values were generated and ranked for the elements affecting fee escalation to see their relative significance. It was found that there has been a moderate degree of charge increase within the initiatives studied, from 12% to 21%. The mitigation modalities observed with the aid of the projects, particularly inserting escalation clauses in contractual agreements, making changes requiring funding and increasing time limits, seem to be inadequate, as they do not provide a foundation for choices and remedy of disputes instead of mitigating the escalation of tasks starting from 3.21% to 12%. KEYWORDS: Escalation, Mitigation, Price, Construction projects.","PeriodicalId":51814,"journal":{"name":"Jordan Journal of Civil Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48101666","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}
Amjad Issa, Saleh Qanazi, E. Natsheh, Abdallah Rashed
This paper aimed at utilizing GIS software in calculating pavement condition index )PCI( values, using four different interpolation methods: IDW, spline, trend and kriging. The case study covers four major streets in Nablus city with a total length of about 6.50 km. The PCI values were calculated using the ASTM conventional method. The four streets were divided into equal 100- meter sections. The PCI values were also calculated for each point of defect in both directions of the streets. The results of the four methods (point by point of defects) were compared manually with the conventional method (ASTM procedure). The results showed that the spline method had a strong correlation with the conventional method in terms of multiple R and R-square calculation (multiple R for left 0.918, right 0.947 and R2 for left 0.843, right 0.897). This method also fitted the data better than the other methods, as seen from the linear regression model results, in addition to producing the minimum error value. The results indicated that by identifying the PCI value, it would be possible to select the proper pavement maintenance and corresponding cost for each point of defect. This in turn would help in prioritizing pavement sections. KEYWORDS: Pavement condition index (PCI), GIS, Interpolation, Distress, Maintenance, Spline.
{"title":"Assessment of Existing Pavement Distresses Utilizing ArcMap-GIS: The Case of Nablus City","authors":"Amjad Issa, Saleh Qanazi, E. Natsheh, Abdallah Rashed","doi":"10.14525/jjce.v17i2.07","DOIUrl":"https://doi.org/10.14525/jjce.v17i2.07","url":null,"abstract":"This paper aimed at utilizing GIS software in calculating pavement condition index )PCI( values, using four different interpolation methods: IDW, spline, trend and kriging. The case study covers four major streets in Nablus city with a total length of about 6.50 km. The PCI values were calculated using the ASTM conventional method. The four streets were divided into equal 100- meter sections. The PCI values were also calculated for each point of defect in both directions of the streets. The results of the four methods (point by point of defects) were compared manually with the conventional method (ASTM procedure). The results showed that the spline method had a strong correlation with the conventional method in terms of multiple R and R-square calculation (multiple R for left 0.918, right 0.947 and R2 for left 0.843, right 0.897). This method also fitted the data better than the other methods, as seen from the linear regression model results, in addition to producing the minimum error value. The results indicated that by identifying the PCI value, it would be possible to select the proper pavement maintenance and corresponding cost for each point of defect. This in turn would help in prioritizing pavement sections. KEYWORDS: Pavement condition index (PCI), GIS, Interpolation, Distress, Maintenance, Spline.","PeriodicalId":51814,"journal":{"name":"Jordan Journal of Civil Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49653569","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}
Permanent ground deformations (PGDs) induced by slope failures cause catastrophic damage to buried pipelines. This paper presents a 2D plane-strain numerical analysis of the behavior of a 800 mm water transport pipeline buried in the Aine-Tine slope (Mila, Algeria) subjected to shallow PGD, as it could be triggered by the recent earthquake of August 07th, 2020 (M= 4.9). The analysis is carried out through the application of an incremental displacement to simulate the soil-pipeline interaction while focusing on the effect of (1) the magnitude of the PGD and (2) the rigidity of the pipeline on the structural response of the pipeline. The elasticperfectly Mohr-Coulomb model was used to simulate the soil behavior and the elastic model was used to simulate that of the steel pipe. Pipeline deformations (i.e., translation and ovalization) and radial internal forces’ (i.e., axial forces F, shear forces Fୗ and bending moments M) results highlighted that shallow PGD can exert additional loads on pipelines that are proportional to the magnitude of the PGD. It has been found that the soil deformations as well as the internal forces induced on the pipeline ring are higher for rigid pipelines. Moreover, the results indicated that rigid pipelines are more effective than flexible ones as far as ovalization-serviceability limit state is concerned. In effect, for PGD magnitudes of 0.5, 1 and 2 m, the ovalization values of the flexible pipeline are, respectively, higher by 23%, 21% and 18% than those calculated for the rigid pipeline. Through a simplified linear numerical simulation such as that presented in this study, engineers and planners could be guided to foresee the possible causes of pipeline leaks and the mechanisms of ruptures that lead very often to severe disruption of pipelines’ normal operation. KEYWORDS: Soil-structure interaction, Slope failure, Permanent ground deformation, Pipelines, Radial internal forces, Ovalization
{"title":"Numerical Investigation on Buried Pipelines Subjected to Permanent Ground Deformations Due to Shallow Slope Failure","authors":"Mohammed Bouatia, R. Demagh, Z. Derriche","doi":"10.14525/jjce.v17i1.07","DOIUrl":"https://doi.org/10.14525/jjce.v17i1.07","url":null,"abstract":"Permanent ground deformations (PGDs) induced by slope failures cause catastrophic damage to buried pipelines. This paper presents a 2D plane-strain numerical analysis of the behavior of a 800 mm water transport pipeline buried in the Aine-Tine slope (Mila, Algeria) subjected to shallow PGD, as it could be triggered by the recent earthquake of August 07th, 2020 (M= 4.9). The analysis is carried out through the application of an incremental displacement to simulate the soil-pipeline interaction while focusing on the effect of (1) the magnitude of the PGD and (2) the rigidity of the pipeline on the structural response of the pipeline. The elasticperfectly Mohr-Coulomb model was used to simulate the soil behavior and the elastic model was used to simulate that of the steel pipe. Pipeline deformations (i.e., translation and ovalization) and radial internal forces’ (i.e., axial forces F, shear forces Fୗ and bending moments M) results highlighted that shallow PGD can exert additional loads on pipelines that are proportional to the magnitude of the PGD. It has been found that the soil deformations as well as the internal forces induced on the pipeline ring are higher for rigid pipelines. Moreover, the results indicated that rigid pipelines are more effective than flexible ones as far as ovalization-serviceability limit state is concerned. In effect, for PGD magnitudes of 0.5, 1 and 2 m, the ovalization values of the flexible pipeline are, respectively, higher by 23%, 21% and 18% than those calculated for the rigid pipeline. Through a simplified linear numerical simulation such as that presented in this study, engineers and planners could be guided to foresee the possible causes of pipeline leaks and the mechanisms of ruptures that lead very often to severe disruption of pipelines’ normal operation. KEYWORDS: Soil-structure interaction, Slope failure, Permanent ground deformation, Pipelines, Radial internal forces, Ovalization","PeriodicalId":51814,"journal":{"name":"Jordan Journal of Civil Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42912671","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}
Swelling in compacted soils may lead to some damages to structures and buildings. For the sake of reducing such damages, soil swelling should be determined, so as to make the structures exhibit adequate resistance against such a phenomenon. For most cases, fully non-linear relations have been observed between soil swelling and the parameters contributing to swelling in compacted soil. As such, soil swelling should be determined via either experimentations or prediction models. However, being extremely timely, swelling tests require special expensive equipment. Accordingly, there is a need for models which can use available data to theoretically give swelling estimations of a relatively high accuracy without getting busy with swelling tests and associated issues. Investigated and evaluated in this research are the ability and application of an adaptive neuro-fuzzy interference system (ANFIS) developed by subtractive clustering and fuzzy c-mean clustering to determine and predict swelling in compacted soils. The results along with the obtained values of root mean squared error (RMSE), mean absolute error (MAE) and coefficient of correlation (R) indicated that the proposed ANFIS model succeeded to predict swelling in compacted soils at a good level of accuracy. Therefore, ANFIS models can be used to predict swelling without getting busy with swelling tests and associated issues. KEYWORDS: Swelling of compacted soil, Subtractive clustering, Fuzzy c-mean clustering, ANFIS, Prediction.
{"title":"Swelling Prediction in Compacted Soils Using Adaptive Neuro-Fuzzy Inference System","authors":"M. Jokar, S. Mirassi, Meisam Mahboubi","doi":"10.14525/jjce.v17i1.09","DOIUrl":"https://doi.org/10.14525/jjce.v17i1.09","url":null,"abstract":"Swelling in compacted soils may lead to some damages to structures and buildings. For the sake of reducing such damages, soil swelling should be determined, so as to make the structures exhibit adequate resistance against such a phenomenon. For most cases, fully non-linear relations have been observed between soil swelling and the parameters contributing to swelling in compacted soil. As such, soil swelling should be determined via either experimentations or prediction models. However, being extremely timely, swelling tests require special expensive equipment. Accordingly, there is a need for models which can use available data to theoretically give swelling estimations of a relatively high accuracy without getting busy with swelling tests and associated issues. Investigated and evaluated in this research are the ability and application of an adaptive neuro-fuzzy interference system (ANFIS) developed by subtractive clustering and fuzzy c-mean clustering to determine and predict swelling in compacted soils. The results along with the obtained values of root mean squared error (RMSE), mean absolute error (MAE) and coefficient of correlation (R) indicated that the proposed ANFIS model succeeded to predict swelling in compacted soils at a good level of accuracy. Therefore, ANFIS models can be used to predict swelling without getting busy with swelling tests and associated issues. KEYWORDS: Swelling of compacted soil, Subtractive clustering, Fuzzy c-mean clustering, ANFIS, Prediction.","PeriodicalId":51814,"journal":{"name":"Jordan Journal of Civil Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48565099","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}
Carbon dioxide can react with alkaline carbonate substances in cement-based materials, which harms the durability of the concrete structure. The carbonation reaction is a process of releasing water, resulting in an increase in pore water saturation, which was always neglected by previous studies. In this paper, a transient pore water saturation equation is proposed and introduced into the classical carbonation reaction kinetic model, which is simulated by finite-element software with a typical ordinary Portland cement. The model was verified by two classical empirical equations for carbonation-depth prediction. The simulation results indicated that the increment of pore water saturation originated by carbonation-produced water will weaken the CO2 diffusivity and enhance the carbonation resistance. Besides, the growth rate of carbonation depth is slightly faster without considering the produced water and with higher initial saturation, the difference will be more significant. If the influence of carbonation water is ignored, the predicted carbonation depth of unsaturated concrete may be less accurate. This study can provide some reference for theoretical and experimental studies on concrete carbonation. However, future work is still needed including more realistic effects in the model such as the mesoscale modeling of concrete and the integration of stress states. KEYWORDS: Ordinary Portland concrete, Carbonization reaction, Carbon-dioxide transport, Finite-element method, Pore saturation.
{"title":"Study of Carbonation-depth Prediction of Unsaturated Concrete Considering Carbonation-produced Water","authors":"J. Long, Zhigao Peng, Haoxiong Feng, Aocheng Yang","doi":"10.14525/jjce.v17i1.08","DOIUrl":"https://doi.org/10.14525/jjce.v17i1.08","url":null,"abstract":"Carbon dioxide can react with alkaline carbonate substances in cement-based materials, which harms the durability of the concrete structure. The carbonation reaction is a process of releasing water, resulting in an increase in pore water saturation, which was always neglected by previous studies. In this paper, a transient pore water saturation equation is proposed and introduced into the classical carbonation reaction kinetic model, which is simulated by finite-element software with a typical ordinary Portland cement. The model was verified by two classical empirical equations for carbonation-depth prediction. The simulation results indicated that the increment of pore water saturation originated by carbonation-produced water will weaken the CO2 diffusivity and enhance the carbonation resistance. Besides, the growth rate of carbonation depth is slightly faster without considering the produced water and with higher initial saturation, the difference will be more significant. If the influence of carbonation water is ignored, the predicted carbonation depth of unsaturated concrete may be less accurate. This study can provide some reference for theoretical and experimental studies on concrete carbonation. However, future work is still needed including more realistic effects in the model such as the mesoscale modeling of concrete and the integration of stress states. KEYWORDS: Ordinary Portland concrete, Carbonization reaction, Carbon-dioxide transport, Finite-element method, Pore saturation.","PeriodicalId":51814,"journal":{"name":"Jordan Journal of Civil Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45323420","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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