فهرست مطالب babak aminnejad

Shear force is one of the most important influencing forces of structural beams and especially unreinforced deep concrete beams that cause sudden failure and sudden collapse of the structure and for this reason, it is of interest to designers and implementers of structures. The study of the conducted research shows that the proposed methods including the use of artificial neural network cannot predict Provide an accurate description of the behavior of deep reinforced concrete beams against shear force. This research, while specifying the cause of the error of the artificial neural network in estimating the shear strength of deep reinforced concrete beams, presents a solution to achieve accurate results by optimizing the artificial neural network by the meta-heuristic algorithm of particle swarm. For this purpose, 309 laboratory samples of deep concrete beams were collected from the research literature and the particle swarm algorithm was used to optimize the weights in the artificial neural network using MATLAB software. The comparison of the results of this method with the results of these letters and other existing methods that were examined in this research showed that the use of the combination of particle swarm algorithm and optimized artificial neural network to estimate the shear strength of unreinforced deep reinforced concrete beams provides more accurate answers.

Flood is a phenomenon during which the water fills the main channel of the river and spreads on to the floodplains. In some natural rivers as well as artificial canals in cities may be more than one floodplain flank the main channel, which is called multi-stage compound channels. In these channels, when the flood occurs and the main channel is filled, the first floodplain is activated, and then when this floodplain overflows, the second floodplain is activated immediately. One of the hydraulic aspects of these channels is the stage-discharge relationship, which is used to estimate the flow discharge for any given flow depth and hence is an important tool in the river design and management during floods. In this study, the one-dimensional model of interacting divided channel and two-dimensional model of Shiono and Knight, which were previously proposed to calculate the flow discharge in classic compound channels, are developed for multi-stage compound channels.

For one-dimensional model, using Newton's second law and by considering into account the apparent shear stresses at the interface of the main channel and the first flood plain, as well as the interface between first and second floodplains, a linear equation system was derived to simultaneously estimate the average flow velocities in adjacent flow compartments of these sections. Huthoff et al. equation was used for the involvement of apparent shear stresses in the interfaces. In this method, the momentum exchange coefficients were calibrated based on the laboratory data from Singh (2021) in a three-stage rectangular compound channel and using the nonlinear generalized reduced gradient optimization algorithm. To derive the semi two-dimensional model of Shiono and Knight, by depth integrating of the Navier-Stokes equations, a differential equation was obtained in terms of shear stress. Then by applying several appropriate assumptions for Reynolds stresses and secondary flows, a simple equation was obtained in terms of depth-averaged velocity. This equation was solved numerically using finite difference method.

The results of the one-dimensional flow interacting model showed that this method has a good efficiency in estimating the total flow discharges with an average and maximum error of about 2.6 and 5.7 percent, respectively. Meanwhile, the vertical divided channel method which is widely used in water engineering packages, does not provide reliable results with an average error of 9.1% and a maximum error of 17.4%. The results of the numerical solution of Shiono and Knight model showed that there is a good agreement between the observed and calculated lateral velocity distributions. It was also found that the effect of eddy viscosity and secondary currents in this channel is significant and should be considered. The mean and maximum error of this model in estimating the total flow discharges was 2.4% and 4.1%, respectively.

The results of both one- and two-dimensional models proposed in this research showed that these models have a suitable ability to estimate the total flow discharge as well as the subdivision flow discharges in multi-stage compound channels. Investigations showed that in terms of the intensity of turbulence and the strength of the secondary currents, the interface plane between the main channel and the first floodplain is much more affected than the interface between first and second floodplains.

Nowadays, due to the complexity of water distribution systems and their large scale, their design, operation and maintenance require the use of optimal methods, which have become more important than in the past in improving their calibration. The most important issue in the simulation modeling of these systems is the consistency between the calculated and measured data. In the absence of the results of unaccounted water studies in the network, the use of statistical experimental methods is still needed as one of the main elements in model calibration. Based on this, the current research was conducted to investigate the effects of different patterns of unaccounted water based on the calculated water consumption patterns and to determine the optimal pattern of unaccounted water within the water distribution network covering the number of 6 ground reservoirs. The comparison of the statistical parameters showed that the use of the inverse model of the customers' consumption, which is not considered as a water model, for calibrating the hydraulic model of the distribution network, provides more acceptable limits for the closeness of the predicted values to the recorded values of the hourly output of the reservoirs, and therefore It is better to be used in studies related to planning and designs.

The project portfolio is to transfer the strategic needs of the organization to projects and operational activities. If portfolio risk occurs, it can affect the portfolio success metrics and overshadow the achievement of the organization's strategic goals. Despite the important role of portfolio risk management in the success of an organization, no proper analysis of project portfolio risks has been provided yet. The purpose of this study is to investigate the importance of portfolio risks and, selection of the best portfolio risk management strategy using multi-criteria decision-making methods. Due to the ignorance of portfolio level risks, the first step of this research is to identify and select important portfolio risks of projects based on previous studies in this field. The importance of risks in different portfolio management strategies was then assessed using a questionnaire from a group of elites. In this study, the CRITIC method, which is a multi-criteria decision-making method has been used to determine the weight of each risk, during which the importance of each risk is calculated without direct questions from experts, and only using the scores given to each risk in different strategies. After that, different portfolio risk management strategies will be identified and, the best risk management response will be calculated and selected.

Evaporation and Transpiration (including soil water evaporation and transpiration in plants) account for about 60% of the annual atmospheric precipitation on the earth. This process is the backbone of the hydrological cycle and a key element in Water Resources Management and the agricultural sector. The Soil and Water Assessment Tool (SWAT) and the Surface Energy Balance Algorithm for Land (SEBAL) are specialized models that address this problem. A SEBAL model is a tool for estimating the spatial distribution of actual evaporation and transpiration using satellite images such as MODIS, and Landsat 8. Although Landsat 8 images have a higher Spatioal resolution than MODIS images (30 m vs. 1000 m), their Tempoural resolution is lower than that of MODIS images (every 16 days vs. every day). On the other hand, daily MODIS images may not always be usable because of problems such as cloudiness. In addition, the interpretation of numerous satellite images is very time-consuming. In the current study, the evaporation and transpiration values in the catchment area of Karun River were obtained in three dry, normal and wet years (2019, 2020, 2021) using the recalibrated SWAT model based on runoff and crop yield and the SEBAL algorithm. Then the results of the SEBAL algorithm and SWAT model were compared with each other based on the water year conditions. In the second stage of the research, the results of the SEBAL algorithm and the range of changes of the main parameters of this algorithm in the plains of Ahvaz-Mlathani and Al-Baji basins were presented according to the ground data and using the MODIS images from the Terra satellite with a suitable time resolution and OLI sensor from Landsat8 satellite, which has a good spatial resolution.

Construction operation is among the most hazardous sectors in terms of occupational accidents. On the other hand, as construction activities are scattered in different locations; therefore, monitoring their safety is a great challenge. Despite various advantages of implementing safety management in the construction projects, the lack of knowledge of designers in terms of prerequisites and not implementing the safety management system, also the lack of tools and novel technologies in the design stage of construction projects, have caused that the system remain yet to be properly evaluated. The Building Information Modelling (BIM) is one of the technologies that has gained popularity among the project managers. Among the most important applications of this approach, one could refer to its unique capabilities in maintaining the safety of project sites. The main objective in the present research, is identification and prioritizing of preventable safety hazards in the mass housing projects using the integrated multi-criteria decision-making method by applying the building information modelling (BIM) approach. For this purpose in the present research, in addition to interviewing the specialists and experts related to this study, the research works by other researchers has been used. Also, the important criteria for reducing the preventable hazards in the mass housing projects were identified. Then, using the SWARA method, the identified criteria were weighted and in continuation using the WASPAS method the criteria were prioritized based on their importance. The findings of the current research showed that the safety management system criterion with Qi=0.54657 is the most important factor in terms of reducing preventable safety hazards in mass housing projects using the BIM approach.

One of the biggest challenges of the rainfall-runoff model is to accurately determine the rate of water infiltration into the soil as one of the parameters that determine the size and shape of the hydrographs of historical floods. The studies conducted in different climates that show different morphometry of the earth indicate the weakness of widely used methods such as SCS-CN in determining the rate of water infiltration into the soil. For the SCS-CN method, as the soil storage index approaches infinity, the soil moisture ratio approaches 1, and this is due to the limitation of the SCS-CN method. In this research, focusing on this weakness in the basic relationships of loss calculations, and an integrated approach in determining the infiltration of water into the soil, the magnitude of the historical floods in the watershed was analyzed. The importance of this analysis can be in verifying the magnitude of floods, which is the criterion for determining structures or crisis control programs.

Considering that in order to solve the problem of infiltration calculations at the basin scale, and based on the new equations to determine flow losses, a homogeneous but raster criterion is needed, in this research, based on the sensitivity of the produced flow to the amount of losses in the probabilistic investigation of the index humidity and flow ratio, a depth-infiltration model was prepared from the two-dimensional comprehensive model in the range. In this study, based on the new relationships of losses determination, numerical calculations were done in the software and script environment sequentially and based on the outputs of the hydrological model. First, the HEC-HMS rainfall-runoff model structure was generated with Arc Hydro and HEC_GeoHMS extensions in Shadegan catchment. Then, infiltration parameters were determined by SMA method in the analysis of remote sensing images from the basin. In the next stage, the development of the primary continuous model, calibration and validation was done focusing on soil moisture information. After determining the soil moisture relationship based on the results of the soil wetting model, the artificial unit occurrence hydrograph was determined by determining the flood volume based on the SCS-CN and VIC combined method. 

The general results of the implementation of the hydraulic model of the flood plain showed that the maximum inflow was equal to 3023 cubic meters per second at the 90th hour of the event, and the maximum outflow flood was at the 93rd hour with a figure of 2137 cubic meters per second. The discharge value is assumed to be 0 at the beginning of the calculations. The flow volume at the end of the calculations was equal to 141.03 million cubic meters, which is the remaining volume of 918.36 million cubic meters in the whole event. The difference between the inlet and outlet discharge was calculated as a deficiency of about 6.14%. Also, the layer of flow depth changes shows that the water level in the plain is trying to be at a possible and reasonable level by filling the lower points. So that a large part of the volume of water from the southern strip of the borders of Trava for the active area of modeling will eventually flow into the sea. However, the direction of water movement has even been estimated to be perpendicular to the direct path towards the sea in some cases. These results indicate a maximum depth of 16.4 units in some areas, with a minimum depth of 5.3 units. The important point is that in the plains, according to the cell size, definitely in some cases much lower depths can be calculated. The average depth in active cells is 11.9 meter calculated locally. These figures can change according to different rainfall events.

The results showed that it is possible to verify the infiltration based on the new base distribution equations with a probabilistic condition in the estimation of the basin shape parameter. The amount of hydrograph calibration in response to water infiltration in soil is dependent on the correct estimation of initial soil moisture. Flow losses in large-scale watersheds are obtained more suitably based on SCS-based distribution equations. Numerical and hydrological models such as HEC-HMS or modelers such as HEC_GeoHMS are completely dependent on the DEM raw layer introduced for the purpose of upstream demarcation. Changes in land cover in flat areas can actually produce a closed border of the watershed compared to the reality of the land in different simulation models. According to the basic assumptions such as calibration coefficients, the single hydrograph method can be a good substitute for areas without rainfall-runoff statistics. The TUFLOW software model gave the best response to one-dimensional to two-dimensional flow for Shadgan plain according to the type of boundary conditions.

Due to the sharp decline of the underground water in the country's plains due to their indiscriminate extraction for agricultural purposes, managers are looking for solutions to manage and restore underground water tables. One of the solutions to compensate for the drop in the underground water level, which is one of the most effective factors in destroying the discharge capacity and increasing the quality in the underground water area, scenarios of reducing withdrawal of farming wells and prepare prohibition plans with the least uncertainty based on the regional sensitivity to pollution. The purpose of this research is to predict the flow and pollution conditions of the area based on numerical models, so that the level network and the direction of the underground water flow of the plain using MODFLOW software in a long-term period and the development of the prediction model using Calibration and validation operations should be performed on the base period of the studies in order to be able to implement the forecast scenarios by applying restrictions and reducing harvesting on aquifer exploitation resources, and specifically agricultural wells, until the stage of stable hydrograph extraction of the plain.

This research was carried out with the aim of estimating and predicting the state of pollution in the urban pollution site, using MODFLOW and MODPATH computer programs in GMS software. To achieve this goal, in the first step, the numerical model of the aquifer flow was prepared and calibrated by the MODFLOW code. Then, the MODPATH code was used to track the contaminated particles in the steady-state progressive method. In the second stage, the impact of the scenario of increasing and decreasing the pumping from the exploitation wells on the travel time, the length of the path and the catchment area of the leachate particles leading to them was predicted and evaluated by the regressive method. In the third step, the tracking of particles leading to qualitative sampling wells in the plain was predicted and evaluated by regressive method in steady state.

According to the automatic calibration and validation approach, the underground water flow model produced the least statistical deviation on the optimization parameters. Also, the particle transfer quality model was correctly implemented on the groundwater flow prediction model. In the Babol aquifer, the waste disposal area outside the designated aquifer is saturated. It was observed that, by adjusting the parameters of the simulation of the transfer of residual pollution cloud particles, an estimate of the concentration was applied to the permeable boundaries and the channel network. This means that in the simulation of particle transport, here the source of pollution spread is the channel network and permeable boundaries, which will be directly affected by pollution during periods of rainfall and especially floods. The concentration limit was given to the model in the form of variable figures based on discharge and precipitation in the range and equal to the primary stable threshold of the research subject (landfill). Based on the cumulative diagram of the outlet concentration from the permeable boundary and flow channel in the southeast region, the trend of changes in the cloud pollution concentration diagram, in the qualitative modeling of the plain, shows that in the forecast period, the increase in concentration will increase linearly. Considering that the waste disposal location is outside the plain, the rate of increase in pollution was not very high until the end of the initial simulation. However, the reason for the increase in concentration accumulation volume can be related to the existence of permeable boundaries and severe drop of underground water in this area. In other words, when the underground water level drops too much in the saturation area of the plain, the direction of the flow will move the volume of polluted water towards the aquifer at a higher speed.

If the situation of groundwater withdrawals continues in the same way, in addition to the reduction of the groundwater storage of the plain, the quality of the remaining water storage will also decrease. This causes more serious problems in the agricultural situation of the region. The results of the implementation of quantitative and qualitative model in order to investigate the infiltration of polluted water from the landfill based on the concentration of pollution, showed that there is a high probability of the infiltration of polluted particles from the south wall side to the aquifer during periods of rainfall Event that current is run in the channels accidently. and then the expansion to the sea will actually occur due to the drop in the water level of the Caspian Sea. Water infiltration is more likely in the eastern regions than in the western regions. The reason for choosing the spread of pollution from the eastern waste disposal site in order to show the accumulation of polluted particles and the repulsion from the sea was the same. It is suggested that in the field of policy making, in order to control the plain's leachate crisis, appropriate bed construction and walling of the waste accumulation area should be applied based on the flow direction.

Annually, thousands of tons of rubber tires are producedconsumed, and disposed in Iran.In the past decade, researchers have conducted numerous investigations on the utilization of rubber fibers or rubber granules in concrete and their effects on its mechanical properties. Howeverthe concurrent use of these two materials in lieu of sand and gravel in concrete has not been thoroughly examined.This study explores the effects of simultaneously incorporating these two materials on the mechanical characteristics of rubberized concrete and investigates the environmental implications of rubber utilization in concrete.By examining the results of slump tests conducted on rubberized concrete specimens with water-to-cement ratios of 0.45, 0.50,and 0.55, and incorporating rubber granules and rubber fibers up to 25%, it was observed that the slump exhibited a decreasing trend from 31 to 82 millimeters. Test results indicated a reduction in compressive strength with increasing rubber content. Specifically,13% of the combination of rubber granules and fibers led to a reduction of around 50% in the compressive strength of rubberized concrete compared to the control sample. In the case of a water-to-cement ratio of 0.55, as the rubber granules and fibers were increased from 4 to 25%, compressive strength decreased from 15.78 to 3.19 MPa.Using different water-to-cement ratios and varying percentages of rubberized concrete in the software SimaPro, it was determined that the combination of rubber granules and fibers resulted in an approximate 40% reduction in carbon dioxide gas emissions in the environment.The optimum condition across all ratios was achieved by incorporating 4% rubber granules and fibers.

The use of hydrological models in watersheds has always been of interest to water resources researchers. Hydrological simulation models are valuable tools for investigating challenging issues related to watershed management, such as the effect of climate change on water resources and the effect of urbanization on floods and droughts. Spatial distribution hydrological model WetSpa is used to simulate river flow at basin scale. The model uses the observed topography, land use, soil map, and daily meteorological time series (rainfall, evaporation and temperature) to predict hydrographs and distributional-spatial hydrological parameters of the basin. In this article, the object-oriented, modular and process-oriented model of WetSpa, which is prepared based on the flexible modeling approach, is applied to simulate the daily hydrograph in Khorramabad basin.

The inputs of the model include digital elevation maps, soil type, land use, and time series of precipitation, temperature, and potential evaporation and transpiration, which are from the statistics of 6 meteorological stations in a ten-year period (water year 84-85 until 93-94) is used. After preparing the inputs of the model, at first the maps of the distribution parameters are automatically generated in the map format by the GIS pre-processing component of the model. After that, the model is calibrated using a 5-year statistical period (water year 84-85 to 89-88) of precipitation, temperature, and potential evaporation and transpiration data. The model uses Thiessen polygons to apply precipitation, temperature, and evaporation data. For this purpose, the daily discharges of Jam Anjir hydrometric station located at the outlet of the studied watershed are used. Model calibration is done manually by determining the values of 11 global (general) parameters of the model, so that the best match between simulation and observational hydrograph is obtained. And finally, the validation of the model is carried out based on a 5-year statistical period (water year 89-88 to 94-93) and the values of the global parameters obtained in the calibration stage.

The maps of distributed parameters are produced, which after preparing the inputs of Mashdand's production model showed that the average potential runoff coefficient of the area is 63% and the concentration time of the area is 17 hours. In the following, according to the 11 global parameters, which symbol and range of changes are specified in table (3), the model global (general) parameters values  are obtained in the calibration stage. Comparing the simulated hydrograph by the model and the observed hydrograph in the calibration stage shows that the best match between the observed and simulated data is established with a correlation coefficient of 0.39. Validation of the model is also based on a 5-year statistical period (water year 89-88 to 94-93) and the values of global parameters. The output files of the model illustrate that 26.15% of the precipitation becomes runoff during the calibration period. During the validation period, the share of total runoff from precipitation is 26.42%. Moreover, the simulation results of the model demonstrate the ratio of evaporation to precipitation in the calibration and validation periods is 57.18 and 69.20%, respectively. Additionally, the results of the evaluation of the model based on the Kling-Gupta index (KGE) present the value of 0.68 for the calibration period and 0.74 for the validation period.

In this article, the effectiveness of WetSpa model is investigated in order to simulate the daily flow of Khorram Abad River at Cham Anjir hydrometric station. According to the results obtained from this research, it can be said that the Wetspa spatial distribution model has the ability to simulate the hydrological behavior of the basin with acceptable accuracy. The graphical comparison of the calculated and observed hydrographs for the calibration and evaluation period also shows a relatively good match between the two hydrographs. Examining the results of calculating of the water balance components by the model demonstrates that the outflow in the calibration and validation period accounted for 26.15 and 26.42% of the total precipitation respectively, seems logical considering the major land use of mountains and pastures in the irrigation basin.

Pre-sedimentation basins are considered as the major and important components in water treatment process through conventional method. Because of the high cost of constructing these basins, which is approximately 30% of the total costs of water treatment plants, modeling and optimum performance of pre-sedimentation basins are very important. In pre-sedimentation basins, because of the existence of velocity gradients, secondary and rotational flows occur. In order to increase the performance of a pre-sedimentation basin (clarifier), it is essential to have a uniform and calm flow field. The use of suitable baffle configurations may help forming favorable flow field and increase the efficiency of the pre-sedimentation basins. In order to find the proper position of a baffle in a rectangular sedimentation basin, computational investigations are performed. The first step to optimize pre-sedimentation basin is accurate calculation of the velocity field and the volume of rotation zones. Flow guiding blades can also be used to depreciate the inlet jet and reduce turbulent kinetic energy. Because of the flow complexity and also the effects of scale, physical models can not solely provide a clear understanding of the physics governing the flow field and it is necessary to study this phenomenon numerically along with field and experimental studies. The first step to optimize pre-sedimentation basins is accurate simulation of the velocity field and the volume of rotation zones. In the present study, numerical simulation of flow was investigated in a pre-sedimentation basin using SSIIM and Fluent models. Continuity and momentum equations were solved using finite volume method. Flow analysis was done steady by the SIMPLE algorithm for velocity and pressure coupling. Discrete method of continuity equations, momentum, turbulent kinetic energy, Reynolds stress drop and discretion of pressure equation are standard. The numerical results were calibrated with experimental results of Shahrokhi et al. (2011) and Imam et al. (1984). Flow simulation was performed in 3D and flow velocity profiles were compared with the experimental results in different sections of a pre-sedimentation basin. Then, in order to sedimentation investigation in the pre-sedimentation basin, advection and dispersion equation of sediment concentration was solved simultaneously with the governing equations of flow. The results of the vertical distribution of sediment concentration profiles in different sections of the basin were compared with the experimental and numerical results of other researchers. Finally, the effect of flow guiding blades on the flow pattern and the efficiency of sedimentation in the pre-sedimentation ponds were investigated. The comparison showed that there is a good agreement between numerical and experimental study with an average error of 6%. Flow rate is one of the effective parameters on creating a rotational zone inside the basins. With increasing the inlet flow rate from 0.002 to 0.01 cubic meters per second, the length of the rotational zone has increased 25% and the width of the rotating zone has increased 45%. The secondary and rotational currents formed at the entrance of the basin are two small rotational zones and approaching the middle of the basin and formation of flow separation zones, the number of rotating areas and their dimensions have increased. From the beginning to the middle of the basin, the shear stress is increased. In the sections x = 0.46 m and x = 0.82 m, the amount of shear stress is maximum. Amount of energy in the middle of the depth has decreased by 40% compared to the water level and about 60% compared to the floor of the sedimentation basin. It showed that there is a good agreement between the numerical and experimental results. It also indicated high ability of SSIIM in predicting distribution of sediment concentration profiles in pre-sedimentation basins. With increasing flow depth, the sediment concentration decreases. In the section x = 1.58 m, the sediment concentration near the free surface is 44 mg L-1, which decreased by 57.48% compared to the concentration of sediment in the basin bed. In the case without the guide blade, near the free surface of the stream, the sediment concentration was decreased. Also, in the middle of the basin, due to the turbulence of the flow and the rotational areas, the secondary current strength was maximal and decreased as it approached the end of the basin.

The main idea of developing green buildings is based on the construction of environmentally friendly buildings and energy conservation and sustainable development. Although the concept of green building alone can open the way to achieve such goals, a mechanism for its implementation must also be provided. Therefore, identifying and evaluating the necessary incentives for the development of green buildings has a key role. The main goal of this paper is to evaluate the effectiveness of the incentive measures (policies) influenced on the promotion of green buildings. By reviewing and summarizing the results of the research literature to identify relevant policies in the field of green construction based on different phases of the project's life cycle, a database consisting of 6 major goals and 42 incentive actions (policies) effective on the promotion of green buildings was identified. By developing the comprehensive fuzzy evaluation method and forming the policy-action matrix, policies and policies were evaluated in the direction of further development of green buildings. The results showed that regulatory measures play an important role in all five phases of the life cycle of green buildings. However, it should not be overlooked that due to the obstacles created by regulatory policies for the future green building market, these policies may not be the best approach for green building development. Incentive measures such as financial incentives for the decision-making stage of development, improvement of technical standards and evaluation system, and conversion to an integrated design model in the market and technology are ranked higher than regulatory policies. The results of the present research provide a clear understanding of the adoption of effective incentive policies on the promotion of green buildings.

One of the most important indicators of economic development in a country is regional planning for the construction of infrastructure projects. Public-private partnership (PPP) contracts provide a viable solution for governments to overcome constraints, but due to the complexity, length of time, and high uncertainties of this contractual approach, it carries many risks. Therefore, the main purpose of research is to identify and evaluate the most important risks in PPP projects with a case study in Iranian freeway projects. In the present article, by in-depth study of the research literature and application of the Delphi method, the most important risks of public-private partnership projects were identified then qualitative analysis is performed to determine the significant risks and the risk assessment model is developed using a combination of fuzzy multi-criteria decision making techniques. The results of quantitative risk analysis using FAHP method showed that the first level risks in seven different categories including economic risk and financing, construction, operational, legal, political, other risks and government risks, respectively, have the greatest impact on this type of projects. The results of quantitative risk analysis using FAHP method showed that the first level risks in seven different categories including economic risk and financing, construction, operational, legal, political, other risks and government risks, respectively, have the greatest impact on this type of projects. Also, the results of sub-criteria ranking showed that high financing costs, quality of performance and standards, lack of support infrastructure have the greatest impact on these projects. Finally, the results of FTOPSIS showed that projects A, B and C were more affected by risks, respectively. The findings help with strengthening the capabilities of developing countries for risk management in freeway PPP projects.

One of the greatest issues regarding Iranian concrete dams is the lack of consideration for increasing our knowledge about them and their performance in times of accidents such as floods, earthquakes, and impact load caused by explosion waves. Some of the most significant objectives of this research are an investigation of the effect of TNT content and its distance from the concrete dam, the identification of critical points of the dam, and the impact of fluid on the amount of damage caused by the explosion to the concrete dam under impact load. The analysis used in this research is straightforward. It should be noted that the discovery of the critical points of the dam in the event of an accident, such as an explosion with complex behavior, can minimize human and financial losses. The LBE method was employed in this study. The interaction between the dam and the water behind it is one of the very considerable parameters that influence the deformation of the dam due to the hydrodynamic pressure of the water behind the dam. It is demonstrated by the results that doubling and tripling the amount of TNT leads to an increase in the pressure on the crest of the full dam by 46.63% and 64.68% respectively; besides, by multiplying the amount of TNT by four and five, the mentioned pressure increases by 70% and 75.58%, respectively.

Accurate data about runoff in the future in a watershed facilitates managers' decisions in water-related decisions and helps conserve natural resources for sustainable development. The two factors of cost and exact time are directly related to accurate runoff estimation. Using computer models to simulate natural phenomena such as the hydrological cycle is one way to reduce costs and increase accuracy.

The information for this research was obtained through the SWAT model website and global data. This study evaluates the accuracy of different calibration and validation methods in the hydrological simulation of Qarasu watershed, the SWAT (hydrological model) and a comparison between GLUE and PSO methods with the SUFI-2 method were used to calibrate the SWAT model. For simulation, 13 specific parameters were selected in all methods in the same situation. It should be noted that the data required for this research were collected from (SWAT model website) and (Water Resources Management Company).

All three methods were able to simulate runoff with acceptable R2 and NSE results (above 0.7), and the sensitivity analysis showed that Sol_K, CH_N2 and CN2 were more sensitive than other parameters.

Although the SUFI-2, PSO, and GLUE algorithms can reduce the difference between the observed and simulated data, the performance of the SUFI-2 algorithm in runoff simulation is more accurate than other algorithms. Therefore, it is suggested to use this algorithm to predict runoff.

In recent years, due to the increase in population, demands, and water consumption, the limitation of freshwater resources on the one hand, and the lack of comprehensive and targeted management programs in the water resources sector, on the other hand, there are many problems facing water resources management. It has created countries. One of the sources of water wastage in water supply systems is the presence of illegal connections.This research investigates the effect of illegal connections on the transient pressure signal in viscoelastic pipelines. This research can be the basis for detection methods of illegal connections based on transient flow analysis in the future. Most past research has been done numerically to detect illegal connections based on transient flow. More work has been done on the elastic pipe system than the laboratory research.

In this research, building a laboratory model of a suitable viscoelastic polyethylene pipe system has been tried to investigate the effect of illegal connections on the pressure signal at Shahid Chamran University of Ahvaz, Ahvaz. The experimental program consisted of hydraulic transient tests with simulated illegal connections. The pipeline is made of HDPE with PE100 and NP16 bar. The pipeline's total length is about 158 meters, with built-in sloping rings upwards. The pipes are fixed to a metal structure to restrain them from axial movement.The analysis includes removing noise from experimental signals, calculating overpressure in the time domain, and generating the system's frequency response using a Fast Fourier transform (FFT). There are different methods to remove the noises in the laboratory pressures. However, to avoid removing the valuable information of the pressure signal, by comparing different noise removal methods, including moving average, a frequency filter, etc., the best method for the transient was using the Butterworth low-pass frequency filter. In this method, by transferring the pressure signal from the time domain to the frequency domain, the high frequencies of the wave, which are mainly caused by environmental conditions, are removed, and the low frequencies of the signal are preserved.

  Comparing the behavior of an intact pipe system and a pipe with a leak showed that compared to these systems, the pipe with an illegal connection has a more complex behavior and cannot be solved with a multi-step approach. In fault-finding methods based on transient with this behavior that causes a phase change in the signal, it is inevitable to optimize all the decision variables together or look for another mathematical approach to solve such problems. Knowing the behavior of a viscoelastic pipe with an illegal viscoelastic connection can be a way to decide to provide new solutions in the frequency domain.

Comparing the effect of the illegal connection with different lengths shows that with the increase in the length of the branch, its reflection is more intense and its impact on lowering the pressure signal is more evident. In general, the illegal connection's presence causes the signal's phase change, which increases over time. The comparison of the effect of transient intensity on the pressure response of the pipe system with the presence of the illegal connection shows that with the increase in the transient intensity, only the signal difference increases, which is caused by the more substantial reflection of the illegal connection. Also, approaching the transient valve, the amount of phase difference becomes more intense with time and the contrast of signals increases. The comparison of pressure fluctuations in the time domain shows that the activation of the bifurcation exerts more attenuation on the transient flow wave. However, there is no noticeable phase change in the pressure signal.

One of the most important concerns of the drilling industry is reducing the negative impacts of drilling cuttings of oil-gas wells. The increasing growth of the oil industry and drilling of oil and gas wells led to large amounts of drilling waste. In this study, drilling cuttings in concrete as a substitute for part of the cement used in the construction industry has been investigated. In this study, the possibility of using drilling cuttings of formations of Bangistan group, including siltstone and sandstone, in concrete production has been evaluated as a substitute for part of the cement in concrete. For this purpose, laboratory studies have been conducted to quantify the compressive strength of concrete samples. The optimum use of drilling cuttings is 25%, which it reduces the total strength of concrete samples by 34%. In addition, the effect of air ash and silica fume additives on improving the compressive strength of concrete samples containing drilling cuttings has been investigated. The test results showed that the addition of these materials had a significant effect on increasing the compressive strength of concrete samples containing 25% of drilling cuttings so that the lost compressive strength is reduced from 34% to less than 2%.

The present paper aimed to develop a bridge management system using a combination of new fuzzy multi-criteria decision making methods. The developed system consists of a three-phase protocol. In the first phase, using past studies, personal intuitions and judgments and experts' experiences, a database containing critical factors affecting the critical condition of bridges was prepared, as well as identifying a number of urban overpass bridges in Tehran city with relatively similar characteristics and in need of maintenance. In the second and third phases, considering the uncertainties in the decision-making problem, by combining Delphi-SWARA-ARAS methods in a fuzzy environment, while screening and prioritizing more efficient and effective critical factors, the critical situation was assessed and the steps studied were selected. The results of Fuzzy SWARA method to determine the effective final factors showed that the factors of seam filling and discontinuity of the bridge related to the main structural index, average and duration of maximum annual rainfall at the bridge location of the main index of climate and hydrology, drainage, water discharge Surface and insulation of the bridge from the main index of safety, proximity and convenience of bridge access to adjacent arterial roads in terms of the main index of strategic (regional) importance, cost-benefit ratio for maintenance or reconstruction and replacement of the bridge from the main budget index and finally The volume of traffic passing over the bridge has gained higher ranks than the main index of traffic and pavement, respectively. Also, the results of Fuzzy ARAS method based on final critical factors (18 factors) showed that among the 24 bridges, Sheikh Fazlollah-SattarKhan, Hakim-Sheikh Baha'i, Hemmat-Africa, Lashkari-Aircraft industries bridges And Resalat-Haqqani with usefulness of 3.226, 3.171, 3.081, 3.080 and 3.077, respectively, are considered as the most preferred bridges in terms of the need for maintenance allocation.

The most important goal in the planning and optimal operation of the reservoir system is to determine the various operating policies that can operate properly Under the drought condition and existing uncertainties. In this study, a combination of the Horse herd optimization algorithm (HOA) and WEAP simulator model was used to extract the optimal reservoir exploitation policies in the form of specific optimization and objective functions were calculated based on the results of the implementation of each scenario and the total operating period for Maroon and Jarreh reservoir dams. The results showed that the average error of the optimal rules extracted from the support vector machines relative to the output of the HOA algorithm in the validation stage is less than 17%, which indicates the high efficiency of this method in predicting the optimal pattern of the dam control curve in real-time. Moreover, evaluation of different scenarios showed that agricultural development in areas 1, 4, and 5 of Ramhormoz will be reduced by an average of 50% and also a 10% reduction in inflow to Marun and Jarreh dams will have negative effects on Shadegan wetland.

With the growth of the urban population and the development of cities, water distribution systems have become very important. Considering the complexity of these systems and the large scale of decision-making in analysis, design, operation and maintenance, the need for computer modelling of networks has become more important. The most important issue in modelling is consistency between calculated and measured data. The amount of unaccounted water in a distribution system can be determined by conducting water balance studies in the system or in an enclosed measurement area. It can be seen that determining the optimal pattern of unaccounted water to complete the data of total water consumption in the network in a seta model, in a situation where the results of unaccounted water studies are not available, is still needed as one of the main elements in model calibration. . In order to solve this problem, the current research was carried out in order to review and improve the continuous model of water distribution network by introducing, checking and implementing an optimal integrated experimental approach of the unaccounted water model. The use of the option of the inverse model of the customers' consumption is not considered as a water model; for calibrating the hydraulic model of the distribution network, it provided a more acceptable simulation in the maximum range from 30% to 4% and in the average maximum difference from 23% to 3%.

The present study was carried out to investigate the quantitative and qualitative status of water resources in Varamin plain and to provide suitable management strategies for sustainability and outflow from current and future challenges in this area. Therefore, statistics and the necessary data were gathered and used WEAP software to provide appropriate management solutions for the impact of the continuation of current water resources policies in the region over the next20 years, by considering the population growth. The results showed that if the current status of water resources continues, we have to harvest more of the surface water resources to cover the increased drinking water demand, based on the increasing population of this area. So that this overdrawn would reach about a 10.8Million cubic meters in 2035. Also, the average annual no coverage of agricultural and industrial demand in the year 2035was 76 and 23 million cubic meters, respectively, 16/2 and 27/4 percent. This overdrawn could reflect the adverse effects on the Mamlu dam, increase in the ground subsidence and increase other economic- social issues. So that, it causes to reduce the average annual volume of the aquifer to around 35 million cubic meters and a 1centimeter daily average drop in the aquifer during the 20-year period. Therefore, due to the high evaporation rate in the region, using artificial feeding methods, such as reducing the amount of evaporation, is a solution to compensate for some of the water shortages in some areas. Therefore, collecting surface water, feeding water underground, and proper water management, using modern water management practices is some of the most important factors in water resource management.

Water is the most important issue for the survival of all people in the society. The smallest disruption in the water supply in people's lives and livelihoods brings the greatest threat to life. However, the interweaving of water issues (major problems and threats) and national security is one of the most important problems of governance in the new era. Building a strategic vision to turn threats into opportunities in these two areas is one of the requirements of good governance. By understanding the issues in the field of water resources and how it is related to the issues raised in the field of national security, this essay is trying to provide a strategic view with the aim of turning these threats into new opportunities. Reducing the negative effects of climate change requires knowing the power and capacity of water resources. This research tries to improve and optimize the methods and modify the structure of intellectual engineering to solve the problems caused by it in the field of water. In this research, the issue is investigated using geomorphological evidence and climatic heritage. This research can be categorized as theoretical-practical in terms of its purpose.

Evaporation is one of the wasteful methods of water resources in geographical areas and is of special importance in the study of water resources.

In the present study, databases including Chah Nimeh dam evaporation data and large-scale network data have been prepared. The SDSM model is used to simulate the evaporation of the coming decades under three scenarios: RCP2.6, RCP4.5 and RCP8.5. The basic modeling period is from 1983 to 2005 (23 years)

Comparison of evaporation estimates for the next two time periods and under different scenarios showed that for the time period 2100-2080 scenarios RCP2.6 and RCP8.5 estimated higher values for evaporation. Examination of inputs showed that air temperature, geopotential height and wind indices have the greatest impact on the evaporation of wells in Sistan.

The results of this study showed that the rate of evaporation in the period of increasing 2100-2080 will experience more than 300 mm per year. The greatest increase in evaporation will be in the warm period of the year.

The leakage is one of the main challenges in the operation of water distribution networks. In the present study, leakage location is detected using Feedforward Artificial Neural Networks (ANNs). For this purpose, two scenarios are considered for training the ANNs. In the first scenario, two simultaneous leakages with equal values, and in the second scenario, two simultaneous leakages but with unequal values are applied to every pair of network node. The training data are analyzed by EPANET2.0 hydraulic simulation software linked with the MATLAB programming language. In both scenarios, first, ANNs are trained using flow rates of total pipes number. Then, sensitivity analysis is performed by Hybrid ANNs for the flow rates of different percent of pipes number. The results of the proposed Hybrid ANNs indicate that in the first scenario, by having the flow rates of 10% of the total pipes, the locations of two simultaneous leakages are successfully determined. However, for the second scenario, while the difference between the two leakages is less than 80% of the maximum leakage (up to ratio value of 10 and 90 % leakages), by having the flow rates of 10% of the total pipes, the locations of the two leakages are still successfully determined. But for larger differences, only the location of the bigger leakage can be detected. Despite the complexities of the second scenario, the proposed ANNs could successfully detect the location of the bigger leakage.

Sustainable production from hydrocarbon resources is very important in economic stability, maintaining production capacity, and fulfilling the export commitments of governments in providing energy sources from hydrocarbon fuels. Drilling and completing oil and gas wells in the safest and most efficient manner is possible in order to meet sustainable production objectives from oil and gas reserves. One of the threats to sustainable production from oil and gas reservoirs is the wellbore integrity failure and missing isolation for various underground layers from the inner space of the well. Alternatively, the leakage of gas and saltwater from the liner lap or casing shoe due to the micro-annulus phenomenon at the margin of the cement bond is another threat to oil and gas wells. To fulfill the aims of separating subsurface layers and directing the appropriate flow of hydrocarbon fluid to the production duct, the cement sheath acts as a sealing barrier against formation layers with varying fluid content and pore pressure. Cement slurry is pumped to the annular space after driving the steel casing. Improving the properties of cement structures is a continuous technical-engineering effort to increase the durability of structures and prevent the destruction or occurrence of problems related to weakness in these structures. Cement design requirements for oil and gas wells are accompanied by perfect sealing of the well. This research seeks to provide an efficient solution to cover the gas and fluid migration issues due to cement sealing inefficiency. Combining the superior rheological properties of latexes in cement with the strength properties of silica nanoparticles is an idea that has been developed in this research. In experiments, the effect of silica nanoparticles on improving the compressive strength of cement, reducing porosity, and effective permeability in gas migration has been well established. Polymer latex also helps cement slurry by developing thixotropic properties in the slurry and reducing the transient time window to minimize the gas migration possibility in critical times when the cement column is not able to effectively resist the formation fluids and restrict the opportunity for formation fluid invasion.