نشریه مهندسی سازه و ساخت
سال نهم شماره 11 (پیاپی 64، بهمن 1401)

The purpose of this study is to evaluate the scientific outputs of the project management literature and draw a scientific map. The target population of this research is all documents indexed in Scopus database which have used the keywords of project management in their title, abstract or keywords. In this regard, 107438 documents were extracted and their process of citation was examined using BibExcel and VOSViewer software. The results showed that the project management research process has been growing exponentially, especially in the last two decades; so that 86% of scientific productions belong to this period and English language with 86% was the dominant language of published scientific documents. Also in the development of this branch of science, the international journal of project management was the most prominent publication with the most documents (2154) and the most citations (105959), and the United States was the most prominent country with 29,271 documents and 360,708 citations. In addition, the analysis in the evaluation of the role of institutions and researchers in the development of project management knowledge, showed that the American institute of electrical and electronics engineers with 133 documents and the department of building and real estate of Hong Kong polytechnic university with 3787 citations, respectively, were in the first place of the most active and influential institutions; And researchers Scott and Keil, with 100 documents and 5,625 citations, respectively, were among the top active and influential researchers. Finally, keyword analysis showed that the word project management with the repetition in 10581 documents and the word ethnography with 67.2 of the average citations, obtained the most repetitions and citations; At the same time, the emergence of up-to-date keywords such as digital transformation, the industry 4.0 and gamification, indicated that recent research has shifted towards the management of technological and innovative projects.

In most seismic design codes, lateral loads are reduced by applying the response modification coefficient in the linear static analyses. Hence, the lateral displacements of the structure should be increased to obtain a realistic estimation of the actual displacements. In this regard, static drifts are multiplied by a deflection amplification factor (Cd). This factor is proposed based on single earthquakes in seismic codes such as ASCE 7 and Standard No. 2800 (4th Edition) while structures in seismic regions will typically be exposed to a number of aftershocks after a major earthquake. Since, the repair of the structures will not be practically possible before exposing to aftershocks, ensuring the proper performance of structures under successive earthquakes is essential. Accordingly, in this paper, deflection amplification factor has been evaluated for dual system of special moment-resisting frame with shear wall under critical seismic sequences. For this purpose, 3 RC building frames with the number of 3, 7 and 11 story have been subjected to linear static, linear and nonlinear dynamic analyses and the deflection amplification factor has been calculated and extracted for each of them under two states of successive and single earthquakes. The results show that successive shocks do not significantly affect the Cd compared to a single earthquake. In addition, a supplementary study has been performed for a number of single earthquakes (near-fault earthquakes which have been introduced in FEMA P695) to provide more reliable results. This investigation reveals that the proposed values in ASCE7-16 and Standard 2800 are not sufficient for Cd coefficient.

When considering energy efficiency optimization in construction project management, one of the best evaluation criteria is the building life cycle energy analysis; that, includes the embodied energy in the building and the operating energy during the life of the building. The present study consists of two steps; 1- Library, statistical and descriptive study (selection of suitable options for life cycle energy optimization of buildings) and 2- Case study (analysis of embodied energy of construction and operation of the building through modeling in energy simulator software design Builder). The results of the life cycle energy analysis of a real educational building in Tehran with a lifespan of 50 years, taking into account ground heating, in the three states of this building; basic available, optimal and optimal with a green roof showed; That, the amount of life cycle energy of the studied buildings is 51.86, 44.82 and 43.89 GJ / m2, respectively. Also, the annual energy consumption during the operation period of the basic educational building in Tehran was estimated to be equal to 0.80 GJ / m2, although this amount was in the range of values provided in global research, but the amount of energy consumption during the operation period of this building Compared to global cultivars, it is a large and significant amount. The overall results indicated; that, The energy consumption during the life of the studied building in the optimal and optimal with a green roof state was less about 24,220 GJ (equivalent to 3958 barrels of crude oil) and 27,420 GJ (equivalent to 4480 barrels of crude oil), respectively, compared to the existing base state.

In recent years, use of Public-Private-Partnerships(3P) approach has received much attention to implementation of infrastructure projects. Risk identification and analysis in these projects has always been one of the main challenges of this approach. The purpose of this paper is to determine the different levels of risk in 3P water and wastewater projects in Iran using library studies and field surveys. Using a three-phase protocol and developing an integrated method of risk analysis, while identifying and separating risks, different levels of risk in these projects were evaluated. In the first phase, 49 risk factors were identified and divided into 6 main groups including technical(R1), economic(R2), political(R3), legal(R4), environmental(R5) and managerial(R6) risks. In the second phase, in order to extract more critical risks, the risks were analyzed and screened by combining Fuzzy Delphi(FD) techniques and Failure Mode Analysis and Effects(FMEA) using the opinions of experts. Based on the results, 23 sub-risk factors with RPNNormalized values greater than 0.5 were identified as critical risks. In the third phase, different levels of total risks(ORL) were determined by Fuzzy synthetic evaluation (FSE) method in combination with FMEA method. Based on the results of risk groups R2, R1, R3, R4, R6 and R5 with ORL of 7.468, 7.262, 7.132, 6.992, 6.815 and 6.670, respectively, as the most critical risk groups in 3P projects were identified. Risks of allocating financial resources and investor obligations (R2-6), lack of transparency in executive issues and changes in project specifications(R1-1), problems of the government system(R3-5), prolongation of licenses and their renewal(R4-6), integrated management, control and utilization of water resources(R6-8) and climate change and rainfall pattern(R5-2) in each of the above groups were identified as the most important critical risks. Finally, the ORL of 3P projects was set at 7.077, which indicates the high level of total risk of these projects.

Geopolymer concrete has been proposed in recent years as a green alternative to conventional concrete, which can reduce the negative environmental effects of Portland cement production. In this study, the effect of three different factors such as metakaolin replacement, Na2Sio3/NaOH ratio and polypropylene fiber percentage on the compressive strength of geopolymer concrete at 7 and 28 days was evaluated. The results showed that with increasing the ratio of sodium silicate solution to sodium hydroxide, the compressive strength of concrete increases significantly up to 22%. Also, in the analysis of the metakaolin replacement per fly ash, it was concluded that with increasing the percentage of metakaolin replacement up to 30%, the compressive strength of the control sample increased to about 14%. Also, as a general result, adding polypropylene fibers up to 1.5% by volume did not have much effect on the compressive strength of geopolymer concrete. Moreover, the mixed designs obtained along with the compressive strength of the specimens were modeled using the artificial neural network and multivariate regression analysis. Based on the training and testing results, the artificial neural network method in the RMSE and MAE semesters with values of 1.998 and 1.5899, respectively, has an acceptable performance compared to the multivariate regression analysis in predicting compressive strength of geopolymer concrete. In addition, the results of sensitivity analysis showed that Na2Sio3 / NaOH and sample age had the most effect and polypropylene fibers had the least effect in predicting the compressive strength of geopolymer concrete.

Reinforced concrete is one of the most widely used building materials in the construction industry. The sulfate attack on concrete structures is one of the factors effectively causing the reduced durability of concrete and structural damage. In the design and construction of concrete structures, service life, sustainable development, and environmental issues are important indicators considered by researchers in optimizing materials to achieve sustainable concrete with high strength by substituting various types of pozzolans for cement. The present study aims to compare the effects of fly ash and micro-silica on the development of the compressive strength, and electrical resistance of concretes exposed to sulfate-rich waters. The plans of this study include two types of conventional concretes and concretes containing pozzolanic material. Concrete mixing plans in sulfate medium were divided into 11 groups. The first group, with no additive material as a substitution for cement, included one plan (control plan), and the other 10 groups included 8 plans with the substitution of different percentages of micro-silica and fly ash powders for cement in concrete. Accordingly, 81 plans, each with 4 samples (7, 14, 28, and 42-day ages), were constructed to test compressive strength (N=324 plans). The results indicate that in the sulfate medium, with an optimal mixing design, the concrete containing standard sand reinforced with fly ash and microsilica pozzolans had higher strength compared to the concrete with no pozzolan, Moreover, the maximum (a 6% reduction in strength) and minimum (a 28% reduction in strength) durability was obtained for Samples # 5 and 6 of Group 2 and Samples #30 and 31, respectively. Also, with the substitution of 15% microsilica, a 1.58-fold increase in the electrical resistance was observed in the 90 day-old concrete sample compared to the 28 day-old sample

The role of human resources in reducing human resource risks and, consequently, organizational risks and organizational profitability, is an undeniable and very important role, and the role of human resources is something beyond administrative and office roles, which unfortunately this view There is a role for human resource management in most project-oriented organizations and so far the risk of strategic human resource actions, especially in the country's manufacturing industry projects has not been systematically assessed.The present paper aimed to identify the risks affecting human resource management in construction projects and provide an integrated model based on Adaptive Network-based Fuzzy Inference System (ANFIS) for risk assessment. By determining the probability, severity and rate of occurrence of risks, a total of 9 risk factors including (1) lack of maturity and knowledge of specialized staff, (2) job stress, (3) employee motivation, (4) lack of attention to the management process Performance and feedback, (5) lack of financial resources to reward innovative activities, (6) inappropriate payment policies, (7) discriminatory performance between human resources, (8) lack of technical knowledge and skills, and (9) lack of Possession of trust-building skills among employees was identified as critical (unauthorized) risks. The results of correlation coefficient criteria to determine the error value of the two methods presented showed that random data had a higher correlation coefficient than the actual data of experts and the results were satisfactory with high accuracy. Also, qualitative and quantitative analysis of risks by ANFIS method and based on experts' opinions and random data showed that if the risks are not available in projects that are being implemented for the first time or access to the required number of experts, by adopting and selecting appropriate random input data. Fuzzy intervals, instead of experts' opinions and their analysis by ANFIS method, obtain acceptable results.

Pore pressure is one of the most important reservoir-drilling parameters and knowledge of this pressure is essential for drilling costs, well safety and prevention of potential hazards. Research has shown that experimental equations have good performance accuracy only for certain regions. Most of these experimental equations have been compiled and developed based on a limited data set. Therefore, these correlations are valid in the range of changes in the parameters of those fields and are not valid for other areas. Therefore, artificial intelligent methods have given way to empirical equations. In this study, 2827 data related to three wells from one of the oil fields located in the southwest of Iran have been used. The input variables used in this paper to predict the pore pressure include 9 variables that have been selected using the feature selection method. In this study, 4 artificial intelligence algorithms include; random forest algorithm, support vector regression algorithm, artificial neural network algorithm and decision tree algorithm have been used to predict the pore pressure. After reviewing the results, it was found that the performance accuracy of the decision tree algorithm is higher than the other three algorithms (performance accuracy for the entire data set including R2 = 0.9985 and RMSE = 14.460 psi). Among the advantages of this algorithm compared to other algorithms are the best results without the need for statistical knowledge, separation of unnecessary data, short time to prepare data and reduction of relative error by finding the main node of the decision maker and analyzing it. Therefore, it can be concluded that with the development of this technique, it is possible to have high performance accuracy for a small amount of data from each field.

One-dimensional view of optimized design of engineering systems focusing on costs without considering other aspects such as risk and uncertainty in engineering design can increase risks during the operation of that engineering system. This paper indicates that if there are uncertainties in design parameters this cannot always cause poorly system operation, whereas may strengthen that system operation. For this purpose a gravity retaining wall is optimized and the optimal dimensions of that retaining wall are calculated. Then the effect of uncertainties, which are in the design parameters of that optimal gravity retaining wall, on the stability factors is calculated. Finally, using the concept of reliability, the risk in the safety factors of the retaining wall is obtained. In this paper, it is shown that if there is 10% uncertainty in design parameters the uncertainty propagation on safety factors is about (-80,+345)%, but this uncertainty propagation can increase the reliability(positive aspect of uncertainty) and risk(negative aspect of uncertainty) with a probability of 98.6039% and 1.3961% respectively. Then using the reliability block diagram, the total amount of reliability and risk for the gravity retaining wall is calculated which are equal to 79.3169 and 20.6830%, respectively. The innovations of this paper can be listed as below: 1) using Self-Adaptive Genetic Algorithm and Many Objective Genetic Algorithm, which have been used to optimize the retaining wall and calculate the uncertainty propagation on safety factors respectively. 2) calculating reliability and risk using fuzzy set theory.3) using reliability block diagram (RBD) to calculate the overall reliability and risk.

Due to the great importance of traditional structures and masonry materials and their high application, the effective parameters in the load-bearing capacity of these structural forms should be examined. In order to study the behaviour of building materials in traditional buildings and structures, due to the high cost and time-consuming laboratory studies, it is necessary to use software methods with accurate failure criteria. To achieve more acceptable and realistic results in the analysis of brick masonry structures, the Willam-Warnke fracture criterion, which is specific to brittle materials, is generally used. In this paper, the aim is to obtain the Willam-Warnke fracture criterion parameters for the combination of brick and mortar materials in macro modelling. For this purpose, with the help of laboratory studies on the combined materials of brick and mortar, the mechanical properties of these materials have been obtained. Finally, in order to validate the obtained parameters, these parameters were included in the numerical modelling of a semi-circular arch of building materials and compared with laboratory results. The results show that the developed parameters of Willam-Warnke fracture criterion predict the behaviour of building materials with a maximum error of about ten percent and a suitable and acceptable agreement is observed between the results of the analytical and laboratory model.

In this study, the numerical and experimental results of the behaviour of RCC’s with an elliptic cross- section made of NC and HSC enclosed by a GRP casing and a CFRP wrapping were compared. Behaviour refers to the compressive capacity and ductility of columns. The effect of concrete type, casing, wrapping and layers number, were investigated. 12 columns with 200*120 diameter and 600 mm height were made. The columns were divided into two groups from NC and HSC, and each group was divided into two part of three; the first part had a casing and the second without casing. Each part had a column without wrapping, 2nd with one layer, and 3rd column with two layers. Numerical modelling was performed with ABAQUS software and the results were compared with experimental results, which were well matched. The results showed that the wrapping and casing improved the behaviour of the columns. Addition of one layer and two layers of wrapping on average in the experimental method causes an increase of 19.7% and 28.7% in the CC in the 1st group and 11% and 28.7% in the 2nd group and in the numerical method causes an increase of 19.9% and 36.6% in CC in the 1st group and 16.8% and 30.9% in the 2nd group. Averagely, the use of casing increased the capacity in the experimental method by 4.15 times in the 1st group and 3.51 times in the 2nd group; in the numerical method; this increase in the capacity in the 1st group was 4.26 times and in the 2nd group was 3.25 times. Although the casing and the wrapping both create confinement, comparison showed that the casing, due to its greater confinement, has a much greater effect on improving the behaviour of columns, especially columns made of NC.

Reinforced Concrete (RC) Frames cover a large part of our country's structures. Neglect progressive collapse in this type of structures can lead to significant human and financial costs. Most of the regulations related to RC frames have comprehensive measures for resistance to seismic forces but there are only a few general solutions to increase the robustness to progressive collapse have been provided. In this study the effects of using High Performance Fiber Reinforced Cementitious Composite materials (HPFRCC) in the beam-column joints and the effects of its use on the robustness of RC frames against progressive collapse have been evaluated. For this purpose, after verifying the simulations with experimental tests using Opensees software the robustness of two 10-story RC frames under progressive collapse has been evaluated. The performance of the samples was measured using the robustness index proposed by Fascetti et al. The Fascetti robustness index is a combination of nonlinear dynamic and nonlinear static analyzes that evaluate the structural robustness to progressive collapse under multi columns removing scenario. The results of the sample analysis show the use of HPFRCCs materials in the joints beam-column can dramatically improve the robustness of concrete frames against progressive collapse by increasing the stiffness and ductility of the beam-column joints.