Pub Date : 2021-05-01DOI: 10.22075/JRCE.2021.21934.1458
B. Ghanbari, M. Fathi
In this study, the distribution of correlation coefficients between maximum interstory drift ratio (MIDR) of multistorey building structures and ground motion characteristics intensity measures (IMs) is evaluated and compared. For this purpose, a continuum building model is used to estimate the MIDR of multistory building structure including higher mode effects. The MIDRs are computed for building structures with three different lateral resisting systems (structural walls, moment-resisting frames, and their combination) and fundamental periods that ranges from 0.05 to 10s. Nine different ground motion parameters of pulse-like ground motions including PGD, PGA, PGV, Ic, CAV, Ia, SMV, ESD, SMA are selected as ground motion characteristics IMs. The effects of the type of lateral resisting system and the acceleration pulse on the distribution of correlation coefficients are also considered in the study. Based on the assessment results, MIDRs in mid and long-period buildings show a high correlation to PGV, SED and SMV, while a low correlation occurs with respect to PGA and SMA. Also, type of lateral resisting system causes changes in the correlation coefficients and results showed that long-period shear wall structure gives lower coefficients with respect to other structural systems.
{"title":"Correlation between pulse-like ground motion intensity measures and seismic demands of buildings with three structural systems (moment-resisting frames, structural walls and combination of moment-resisting frames and shear walls)","authors":"B. Ghanbari, M. Fathi","doi":"10.22075/JRCE.2021.21934.1458","DOIUrl":"https://doi.org/10.22075/JRCE.2021.21934.1458","url":null,"abstract":"In this study, the distribution of correlation coefficients between maximum interstory drift ratio (MIDR) of multistorey building structures and ground motion characteristics intensity measures (IMs) is evaluated and compared. For this purpose, a continuum building model is used to estimate the MIDR of multistory building structure including higher mode effects. The MIDRs are computed for building structures with three different lateral resisting systems (structural walls, moment-resisting frames, and their combination) and fundamental periods that ranges from 0.05 to 10s. Nine different ground motion parameters of pulse-like ground motions including PGD, PGA, PGV, Ic, CAV, Ia, SMV, ESD, SMA are selected as ground motion characteristics IMs. The effects of the type of lateral resisting system and the acceleration pulse on the distribution of correlation coefficients are also considered in the study. Based on the assessment results, MIDRs in mid and long-period buildings show a high correlation to PGV, SED and SMV, while a low correlation occurs with respect to PGA and SMA. Also, type of lateral resisting system causes changes in the correlation coefficients and results showed that long-period shear wall structure gives lower coefficients with respect to other structural systems.","PeriodicalId":52415,"journal":{"name":"Journal of Rehabilitation in Civil Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79889522","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 : 2021-05-01DOI: 10.22075/JRCE.2021.22366.1475
F. Fasihi, M. Keymanesh, Seyyed Ali Sahaf, S. Ghareh
In most road pavements design methods, a solution is required to transform the traffic spectrum to standard axle load with using equivalent axle load factor (EALF). The EALF depends on various parameters, but in existing design methods, only the axle type (single, tandem, and tridem) and pavement structure number were considered. Also, the EALF only determined for experimental axles and axle details (i.e., axle weight, length, pressure), wheel type (single or dual wheel) plus pavement properties were overlooked which may cause inaccuracy and unusable for the new axle. This paper presented a developed model based on Artificial Neural Network (ANN) for calculation of EALFs considering axle type, axle length, contact area, pavement structure number (SN), tire pressure, speed, and final serviceability. Backpropagation architecture was selected for the model for the EALF prediction based on fatigue criteria. Finally, among all reviewed ANN configuration, a network with 7-13-1 was selected for the optimum network.
{"title":"Calculation of Equivalent Axle Load Factor Based on Artificial Intelligence","authors":"F. Fasihi, M. Keymanesh, Seyyed Ali Sahaf, S. Ghareh","doi":"10.22075/JRCE.2021.22366.1475","DOIUrl":"https://doi.org/10.22075/JRCE.2021.22366.1475","url":null,"abstract":"In most road pavements design methods, a solution is required to transform the traffic spectrum to standard axle load with using equivalent axle load factor (EALF). The EALF depends on various parameters, but in existing design methods, only the axle type (single, tandem, and tridem) and pavement structure number were considered. Also, the EALF only determined for experimental axles and axle details (i.e., axle weight, length, pressure), wheel type (single or dual wheel) plus pavement properties were overlooked which may cause inaccuracy and unusable for the new axle. This paper presented a developed model based on Artificial Neural Network (ANN) for calculation of EALFs considering axle type, axle length, contact area, pavement structure number (SN), tire pressure, speed, and final serviceability. Backpropagation architecture was selected for the model for the EALF prediction based on fatigue criteria. Finally, among all reviewed ANN configuration, a network with 7-13-1 was selected for the optimum network.","PeriodicalId":52415,"journal":{"name":"Journal of Rehabilitation in Civil Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80679638","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 : 2021-05-01DOI: 10.22075/JRCE.2021.20431.1417
N. Hashemi, A. V. Oskouei, A. Doostmohamadi
Many concrete structures need rehabilitation during their service life for different reasons; poor quality of construction, relatively lower compressive strength of concrete, non-compliance with existing or updated design codes, and buildings that experienced an intensive earthquake are to name but a few. One of the solutions to strengthen concrete structures is to install rebar inside the structural components. In this paper, the effect of steel rebar planting with a constant nominal diameter of 8 mm along with two different lengths (i.e., 35 and 55 mm) as well as two different planting angles (i.e., 0 and 45 degrees) have considered as variables. Therefore, the rebar planting process has conducted on 12 low-strength cylindrical concrete specimens with an initial compressive strength of 15.5 MPa. The concrete column specimens were tested under uniaxial compressive load after rebar planting. The results of this study indicated that rebar planting leads to an increase in the initial compressive strength of the concrete specimens in general. The specimens with 35 mm and 55 mm planted length witnessed an average enhancement of 17% and 23%, respectively. Moreover, considering the angle of planted rebar as another variable parameter, the obtained results revealed that the maximum compressive load for both 35 mm and 55 mm specimens with a planting angle of 0-degree and 45-degree almost followed the same increase and improved by an average of 5%.
{"title":"A Rehabilitation Experimental Program on Low-Strength Concrete with Steel Bar Planting","authors":"N. Hashemi, A. V. Oskouei, A. Doostmohamadi","doi":"10.22075/JRCE.2021.20431.1417","DOIUrl":"https://doi.org/10.22075/JRCE.2021.20431.1417","url":null,"abstract":"Many concrete structures need rehabilitation during their service life for different reasons; poor quality of construction, relatively lower compressive strength of concrete, non-compliance with existing or updated design codes, and buildings that experienced an intensive earthquake are to name but a few. One of the solutions to strengthen concrete structures is to install rebar inside the structural components. In this paper, the effect of steel rebar planting with a constant nominal diameter of 8 mm along with two different lengths (i.e., 35 and 55 mm) as well as two different planting angles (i.e., 0 and 45 degrees) have considered as variables. Therefore, the rebar planting process has conducted on 12 low-strength cylindrical concrete specimens with an initial compressive strength of 15.5 MPa. The concrete column specimens were tested under uniaxial compressive load after rebar planting. The results of this study indicated that rebar planting leads to an increase in the initial compressive strength of the concrete specimens in general. The specimens with 35 mm and 55 mm planted length witnessed an average enhancement of 17% and 23%, respectively. Moreover, considering the angle of planted rebar as another variable parameter, the obtained results revealed that the maximum compressive load for both 35 mm and 55 mm specimens with a planting angle of 0-degree and 45-degree almost followed the same increase and improved by an average of 5%.","PeriodicalId":52415,"journal":{"name":"Journal of Rehabilitation in Civil Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76690161","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 : 2021-05-01DOI: 10.22075/JRCE.2020.21032.1437
A. Loghmani, A. Mortezaei, A. Hemmati
One of the most important structural features is fundamental vibration period which depends significantly on the inherent characteristics of structures. Seismic codes and some researchers estimate experimentally and mathematically fundamental vibration period using the number of stories or the overall height of the building. The consequences of evaluating the various relationships have been resulted based on structural height, mass, stiffness and number of stories. As the overall height and the number of stories do not make difference between regular and irregular structures, so it seems that mass and stiffness of each story is so important in zone of building vibration period. Considering the importance of irregular buildings, a new relationship proposed to determine fundamental natural period of vibration for elastic regular and irregular buildings in height using artificial neural network. The accuracy of the proposed relationship is perfectly validated and confirmed by numerical calibrations and matrix analyses.
{"title":"A New Relationship to Determine Fundamental Natural Period of Vibration for Irregular Buildings in Height Using Artificial Neural Network","authors":"A. Loghmani, A. Mortezaei, A. Hemmati","doi":"10.22075/JRCE.2020.21032.1437","DOIUrl":"https://doi.org/10.22075/JRCE.2020.21032.1437","url":null,"abstract":"One of the most important structural features is fundamental vibration period which depends significantly on the inherent characteristics of structures. Seismic codes and some researchers estimate experimentally and mathematically fundamental vibration period using the number of stories or the overall height of the building. The consequences of evaluating the various relationships have been resulted based on structural height, mass, stiffness and number of stories. As the overall height and the number of stories do not make difference between regular and irregular structures, so it seems that mass and stiffness of each story is so important in zone of building vibration period. Considering the importance of irregular buildings, a new relationship proposed to determine fundamental natural period of vibration for elastic regular and irregular buildings in height using artificial neural network. The accuracy of the proposed relationship is perfectly validated and confirmed by numerical calibrations and matrix analyses.","PeriodicalId":52415,"journal":{"name":"Journal of Rehabilitation in Civil Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76320085","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 : 2021-02-01DOI: 10.22075/JRCE.2020.20335.1407
E. Darvishan
Recently soft computing methods have been employed in most fields, especially in civil engineering, due to its high accuracy to predict the results and process information. Soft computing is the result of new scientific endeavors that make modeling, analysis, and, ultimately, the control of complex systems possible with greater ease and success. The essential methods of soft computing are fuzzy logic, artificial neural networks, and genetic algorithm. In this paper, using 74 valid experimental data, estimation of punching shear capacity of FRP-strengthened RC slabs using two powerful methods (artificial neural network and Group method of data handling) has been investigated. The maximum and minimum dimension of column cross-section, the effective height of slab, the compressive strength of concrete, modulus of elasticity of FRP bar, and the percentage of FRP bars were selected as input variables, and the punching shear capacity of the slab was selected as the output variable. Also, in order to investigate the effect of the variables mentioned above on the results, sensitivity analysis is conducted in both methods. Absolute Fraction of Variance for the two methods showed that the GMDH method had higher precision (1.73%) than the ANN method in the prediction of results.
近年来，软计算方法由于其预测结果和处理信息的精度高，已被应用于大多数领域，特别是土木工程领域。软计算是新的科学努力的结果，它使建模、分析和最终控制复杂系统变得更加容易和成功。软计算的基本方法是模糊逻辑、人工神经网络和遗传算法。本文利用74份有效的试验数据，采用人工神经网络和数据处理成组方法对frp加固RC板冲剪承载力进行了估算。选取柱截面最大尺寸、最小尺寸、楼板有效高度、混凝土抗压强度、FRP筋弹性模量、FRP筋占比作为输入变量，楼板冲剪承载力作为输出变量。此外，为了研究上述变量对结果的影响，两种方法都进行了敏感性分析。两种方法的绝对方差分数(Absolute Fraction of Variance)表明，GMDH方法对结果的预测精度(1.73%)高于人工神经网络方法。
{"title":"The Punching Shear Capacity Estimation of FRP- Strengthened RC Slabs Using Artificial Neural Network and Group Method of Data Handling","authors":"E. Darvishan","doi":"10.22075/JRCE.2020.20335.1407","DOIUrl":"https://doi.org/10.22075/JRCE.2020.20335.1407","url":null,"abstract":"Recently soft computing methods have been employed in most fields, especially in civil engineering, due to its high accuracy to predict the results and process information. Soft computing is the result of new scientific endeavors that make modeling, analysis, and, ultimately, the control of complex systems possible with greater ease and success. The essential methods of soft computing are fuzzy logic, artificial neural networks, and genetic algorithm. In this paper, using 74 valid experimental data, estimation of punching shear capacity of FRP-strengthened RC slabs using two powerful methods (artificial neural network and Group method of data handling) has been investigated. The maximum and minimum dimension of column cross-section, the effective height of slab, the compressive strength of concrete, modulus of elasticity of FRP bar, and the percentage of FRP bars were selected as input variables, and the punching shear capacity of the slab was selected as the output variable. Also, in order to investigate the effect of the variables mentioned above on the results, sensitivity analysis is conducted in both methods. Absolute Fraction of Variance for the two methods showed that the GMDH method had higher precision (1.73%) than the ANN method in the prediction of results.","PeriodicalId":52415,"journal":{"name":"Journal of Rehabilitation in Civil Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84819710","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 : 2021-02-01DOI: 10.22075/JRCE.2020.20373.1410
Mansoureh Rezaee Manesh, S. Fattahi, H. Saffari
According to the recent Earthquake records, the earthquake duration is longer in some areas, resulting into more structural damage. One of the important factors in reducing earthquake damages is the separation gap between two adjacent structures. This case study investigated the effect of significant duration of the earthquake on two adjacent steel moment-resisting structures with different heights and near to active fault. The pounding between pairs of three 3, 6 and 9-story steel moment frames was evaluated using a nonlinear time history analysis method considering the reduced stiffness and strength. The results showed that for the intended type 3-soil, the risk of pounding and collapse amplification among the 3- and 6-story buildings are higher than others. This is due to the necessity of the Iranian standard 2800 to calculate the separation gap by the nonlinear methods for the buildings with height more than 8 stories. Also, the analysis of the significant duration of the applied earthquakes demonstrated that this parameter is a determining and effective factor in the pounding of structures, especially the adjacent buildings with defferent heights. It is noteworthy all of the analysis was done by 9 earthquake records. This study recommended using the nonlinear method to calculate separation gap while designing two adjacent steel moment-resisting structures with different heights in the near-field area and on the soft soil.
{"title":"Investigation of Earthquake Significant Duration on the Seismic Performance of Adjacent Steel Structures in Near-Source","authors":"Mansoureh Rezaee Manesh, S. Fattahi, H. Saffari","doi":"10.22075/JRCE.2020.20373.1410","DOIUrl":"https://doi.org/10.22075/JRCE.2020.20373.1410","url":null,"abstract":"According to the recent Earthquake records, the earthquake duration is longer in some areas, resulting into more structural damage. One of the important factors in reducing earthquake damages is the separation gap between two adjacent structures. This case study investigated the effect of significant duration of the earthquake on two adjacent steel moment-resisting structures with different heights and near to active fault. The pounding between pairs of three 3, 6 and 9-story steel moment frames was evaluated using a nonlinear time history analysis method considering the reduced stiffness and strength. The results showed that for the intended type 3-soil, the risk of pounding and collapse amplification among the 3- and 6-story buildings are higher than others. This is due to the necessity of the Iranian standard 2800 to calculate the separation gap by the nonlinear methods for the buildings with height more than 8 stories. Also, the analysis of the significant duration of the applied earthquakes demonstrated that this parameter is a determining and effective factor in the pounding of structures, especially the adjacent buildings with defferent heights. It is noteworthy all of the analysis was done by 9 earthquake records. This study recommended using the nonlinear method to calculate separation gap while designing two adjacent steel moment-resisting structures with different heights in the near-field area and on the soft soil.","PeriodicalId":52415,"journal":{"name":"Journal of Rehabilitation in Civil Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90075402","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 : 2021-01-20DOI: 10.22075/JRCE.2021.19323.1365
M. A. Afshar, D. Afshar
In this paper the effect of axial load on dynamic behavior of a simple frame, subjected to harmonic, seismic and earthquake excitation is investigated. The equations of motion are considered for two types of small and large deformations. The method of multiple scales is applied to solve the differential equations of motion with harmonic loading and for small and large deformations. Then, the steady state response near one-to-one resonance condition is studied. The results show that the dynamic behavior of the frame under axial load is completely different in resonance and non-resonance cases. The equations of motion with earthquake loading is also considered and the effect of axial load in the frame behavior under the time history and the response spectrum of the model is studied. Although white noise as a stochastic loading is applied to the model and, the results are approximated using the method of stochastic differential equations so, the mean value and covariance are calculated and the effect of axial force on them is investigated.
{"title":"Study on Linear and Nonlinear Dynamically P-delta Effects on Frame Structures under earthquake spectra, harmonic and stochastic excitations","authors":"M. A. Afshar, D. Afshar","doi":"10.22075/JRCE.2021.19323.1365","DOIUrl":"https://doi.org/10.22075/JRCE.2021.19323.1365","url":null,"abstract":"In this paper the effect of axial load on dynamic behavior of a simple frame, subjected to harmonic, seismic and earthquake excitation is investigated. The equations of motion are considered for two types of small and large deformations. The method of multiple scales is applied to solve the differential equations of motion with harmonic loading and for small and large deformations. Then, the steady state response near one-to-one resonance condition is studied. The results show that the dynamic behavior of the frame under axial load is completely different in resonance and non-resonance cases. The equations of motion with earthquake loading is also considered and the effect of axial load in the frame behavior under the time history and the response spectrum of the model is studied. Although white noise as a stochastic loading is applied to the model and, the results are approximated using the method of stochastic differential equations so, the mean value and covariance are calculated and the effect of axial force on them is investigated.","PeriodicalId":52415,"journal":{"name":"Journal of Rehabilitation in Civil Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90010502","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 : 2021-01-18DOI: 10.22075/JRCE.2021.21286.1443
A. Haddad, M. Shahverdi
The object of this research is to compare the behavior of floating and end bearing stone columns made of recycled aggregates of building debris with natural aggregate. To do so, both types of stone columns were constructed by crushed concrete and crushed brick as recycled aggregates and compared with the same models made of gravel as natural aggregates. All the columns were constructed with the same size, density, and grading in a clay bed. To evaluate the initial quality of materials of the stone columns, the index tests were performed. The results of such tests illustrated the less resistance of recycled materials in comparison to the natural materials; On the contrary, according to the results of the index tests, crushed bricks are not recommended to construct stone columns. Despite the index tests, results of loading on a floating column filed with natural and recycled aggregate were approximately the same, but the bearing capacity of the end bearing column made of natural aggregates was higher than the same model made of recycled aggregates.
{"title":"Evaluation of Recycled Materials as Aggregate of End Bearing Stone Columns: a Comparative Study","authors":"A. Haddad, M. Shahverdi","doi":"10.22075/JRCE.2021.21286.1443","DOIUrl":"https://doi.org/10.22075/JRCE.2021.21286.1443","url":null,"abstract":"The object of this research is to compare the behavior of floating and end bearing stone columns made of recycled aggregates of building debris with natural aggregate. To do so, both types of stone columns were constructed by crushed concrete and crushed brick as recycled aggregates and compared with the same models made of gravel as natural aggregates. All the columns were constructed with the same size, density, and grading in a clay bed. To evaluate the initial quality of materials of the stone columns, the index tests were performed. The results of such tests illustrated the less resistance of recycled materials in comparison to the natural materials; On the contrary, according to the results of the index tests, crushed bricks are not recommended to construct stone columns. Despite the index tests, results of loading on a floating column filed with natural and recycled aggregate were approximately the same, but the bearing capacity of the end bearing column made of natural aggregates was higher than the same model made of recycled aggregates.","PeriodicalId":52415,"journal":{"name":"Journal of Rehabilitation in Civil Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91288831","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 : 2021-01-18DOI: 10.22075/JRCE.2021.21062.1438
Y. Kheradmand, A. Honarbakhsh, S. M. Movahedifar, A. R. Afshari
The risk management standard published by the Project Management Institute (PMI), entitled Project Management Body of Knowledge (PMBOK), was utilized in the present study as the primary method for evaluation of risk management. The general purpose of this article is to prioritize risk in water and wastewater projects through the analytic hierarchy process (AHP). The statistical population considered here covers all the factors involved in water and sewage projects. Sample size determination was done based on the Morgan table, which resulted in selecting 59 high-expertise experts. The Delphi method, a process used to arrive at a group opinion or decision by surveying a panel of experts, was used for risk identification. After entering the raw data into an Expert Choice program, based on the AHP decision model, data analysis was completed. The obtained results indicate that budget deficit is the most critical risk factor of the project, preceding by inflation and international sanctions. Furthermore, risk factors related to expanding the project relationship with other areas, the area's religious location, and the area's environmental hazards, and the project site are the least important ranking items.
{"title":"Risk Prioritization in Water and Wastewater Projects Using a Decision Model Based on the Analytic Hierarchy Process","authors":"Y. Kheradmand, A. Honarbakhsh, S. M. Movahedifar, A. R. Afshari","doi":"10.22075/JRCE.2021.21062.1438","DOIUrl":"https://doi.org/10.22075/JRCE.2021.21062.1438","url":null,"abstract":"The risk management standard published by the Project Management Institute (PMI), entitled Project Management Body of Knowledge (PMBOK), was utilized in the present study as the primary method for evaluation of risk management. The general purpose of this article is to prioritize risk in water and wastewater projects through the analytic hierarchy process (AHP). The statistical population considered here covers all the factors involved in water and sewage projects. Sample size determination was done based on the Morgan table, which resulted in selecting 59 high-expertise experts. The Delphi method, a process used to arrive at a group opinion or decision by surveying a panel of experts, was used for risk identification. After entering the raw data into an Expert Choice program, based on the AHP decision model, data analysis was completed. The obtained results indicate that budget deficit is the most critical risk factor of the project, preceding by inflation and international sanctions. Furthermore, risk factors related to expanding the project relationship with other areas, the area's religious location, and the area's environmental hazards, and the project site are the least important ranking items.","PeriodicalId":52415,"journal":{"name":"Journal of Rehabilitation in Civil Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79644383","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 : 2021-01-17DOI: 10.22075/JRCE.2021.21194.1439
Mehran Yaghoubi, R. Aghayari, S. Hashemi
Nowadays, Reinforced Concrete (RC) wall-slab systems are being used more extensively due to their effective performance seen in past earthquakes. Progressive collapse is a phenomenon in which all or part of a structure is damaged due to damage or collapse of a small relevant part. The majority of research done in the field of progressive collapse has been on frame-shaped structures. Further, the performance of RC wall-slab structural systems, especially against progressive collapse, has been less studied. In this study, at first, nine concrete buildings of five, ten and fifteen stories with wall-slab structural systems, with the ratio of spans length to the story height (L/H) of 1, 1.5 and 2 and a structural height of 2.75 meters in each story, were designed by the ETABS V16 software. Then, using the SAP2000 software and nonlinear shell-layered elements, nonlinear static analysis was performed by the Alternative Load Path (ALP) method on the models and the results were evaluated. The results demonstrated the relatively high strength of buildings with wall-slab structural systems in withstanding progressive collapse. The rate of vertical displacement of the removal location, the maximum von Mises stress in rebar, the maximum compressive stress and strain in concrete in the interior wall removal scenarios were less extensively compared to the corner wall removal scenarios. In contrast, progressive collapse potential increased significantly with increasing number of stories and the L/H ratio. Also, it was found that, buildings with the wall-slab structural system may exhibit brittle failure behavior influenced by progressive collapse.
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