Amirkabir University of Technology AUT Journal of Civil Engineering 2588-2899 4 4 2020 12 01 Effects of Vertical Deficiency Location on the Structural Behavior of Steel SHS Short Columns 399 410 3165 10.22060/ajce.2018.14940.5507 EN Amin Shabani Ammari Department of Civil Engineering, Zahedan Branch, Islamic Azad University, Zahedan, Iran Kambiz Narmashiri Department of Civil Engineering, Zahedan Branch, Islamic Azad University, Zahedan, Iran 0000-0003-1767-7424 Journal Article 2018 09 06 Structures that face damage require strengthening to reach the initial performance. Strengthening steel Square Hollow Section (SHS) short columns with initial deficiencies were not taken into account appropriately. In this paper, vertical deficiencies with the same dimensions were created at three locations (top, middle, and bottom) on the middle element and the middle of the corner element. Then, the effect of the location of such deficiencies on axial behavior of Carbon Fiber Reinforced Polymer (CFRP) strengthened steel tubular columns was investigated. To this end, a total of nine steel columns were experimentally tested and the same specimens were modeled using ABAQUS V.6.14. In the experimental work, a straight pressure test was performed. In the numerical simulation, three dimensional (3D) simulation method, static gradual loading, and non-linear static analysis were used. The specimens were: no deficiency (Control), four non-strengthened columns with deficiencies at different locations, and four CFRP strengthened specimens having deficiencies. The results showed that vertical deficiencies caused a significant decrease in load-bearing capacity and initial performance. As a result of axial loading, the area of vertical deficiencies experienced local buckling increase and lateral rupture. Local bucking at damaged locations caused the stress concentration, then the axial deformation increased. Vertical deficiencies at the bottom of the middle element caused the most critical conditions. Vertical deficiencies on the corner element led to greater destruction and bearing capacity decline compared to the middle element. Carbon Fiber played a key role in ductility and strength increase around the deficiency by covering it. Using CFRP layers the stress concentration overcame and the local buckling delayed due to high confining strength. https://ajce.aut.ac.ir/article_3165_b299ad862b6f12cb57679f0538eca514.pdf

Amirkabir University of Technology AUT Journal of Civil Engineering 2588-2899 4 4 2020 12 01 Effect of Micro Silica and Slag on the Durability Properties of Mortars against Accelerated Carbonation and Chloride Ions Attack 411 422 3779 10.22060/ajce.2020.15943.5565 EN Ali Akbar Ramezanian Pour Faculty of Civil Engineering, Amirkabir University of Technology, Tehran, Iran Saeed Sedighi civil and environment engineering, amir kabir university of technology , tehran , iran Maziar Kazemian Faculty of Civil Engineering, Amirkabir University of Technology, Tehran, Iran AmirMohammad Ramezanianpour School of Civil Engineering, University College of Engineering, University of Tehran, Tehran, Iran Journal Article 2019 04 06 <strong>Nowadays, as the cities grow, more carbon dioxide is emitted to the atmosphere moreover, chloride ions dissolved in water would reach the concrete whenever it rains consequently, they can help increase the corrosion of bars implemented inside concretes, therefore investigation of the effect of carbonation and chloride ingress is of paramount importance. Mortars were made with three water to cement ratios of 0.485, 0.44, and 0.4 also the flow of the mortars was kept in the range of 18 to 20 centimeters. The mixtures were prepared with ordinary Portland cement and artificial pozzolans (Ground Granular Blast Furnace Slag and Micro-Silica) as supplementary cementitious materials. The cement replacement percentage was 20% intended for slag-containing samples and 7.5% used for micro-silica-containing samples. The durability properties of mortars were investigated through capillary water absorption test, electrical resistivity, carbonation depth, and chloride ions penetration. Also, the mechanical characteristics of mortars were measured by the compressive strength test. The results revealed that Micro-silica enhanced the mechanical and durability properties of the specimens except for their resistance against carbonation, in both environments while, the addition of slag had some drawbacks in compressive strength and carbonation resistance. However, the addition of Slag helped specimens augment other durability properties. It can be concluded that using Micro-Silica is a magnificent option to enhance the mechanical and durability properties of mortars. The contribution of Slag has also been shown to help enhance the durability properties of mortars but not as much as Micro-Silica.</strong> https://ajce.aut.ac.ir/article_3779_8ce87bdda85cd44f14de9afb86491884.pdf

Amirkabir University of Technology AUT Journal of Civil Engineering 2588-2899 4 4 2020 12 01 Developing a Novel Machine Learning Method to Predict the Compressive Strength of Fly Ash Concrete in Different Ages 423 436 3531 10.22060/ajce.2019.16124.5569 EN Hamed Naseri Amirkabir University of Technology Hamid Jahanbakhsh Department of Civil and Environmental Engineering, Amirkabir University of Technology, Tehran, Iran Fereidoon Moghadas Nejad Amirkabir University of Technology Amir Golroo Civil Engineering Department, Amir Kabir University of Technology Journal Article 2019 04 14 <strong>Estimating the compressive strength of concrete before fabricating, has been one of the most important challenges because designing a mixture proportion by experimental methods needs expert workers, consumes energy, and wastes materials. Therefore, in this study, the influences of materials and the age of samples on the compressive strength of fly ash concrete are investigated, and a novel method for predicting the compressive strength is presented. To this end, the water cycle algorithm and genetic algorithm are utilized, and their outcomes are compared with the classical regression models. Various performance indicators are used to gauge the accuracy of the models. By analyzing the results, it is comprehended that the water cycle algorithm is the most accurate model according to all performance indicators. Besides, the outcomes of the water cycle algorithm and genetic algorithm are by far better than those of classical methods. The mean absolute error of water cycle algorithm, genetic algorithm, linear regression, partial-fractional regression, and fractional regression are 3.01, 3.12, 5.47, 9.70, and 5.37 MPa for training data and 2.90, 3.44, 5.47, 9.70, and 5.37 MPa for testing data respectively. Furthermore, the water cycle algorithm is the only algorithm whose mean absolute error of testing data is less than that of training data. At last, it was concluded that the mixture with less than 35% fly ash (weight of the binder) had maximum amounts of compressive strength. Also, the compressive strength of concrete decreased significantly as the amount of fly ash increased more than this definite level.</strong> https://ajce.aut.ac.ir/article_3531_e52ad5c9f751f599492b4f087ed7ecfc.pdf

Amirkabir University of Technology AUT Journal of Civil Engineering 2588-2899 4 4 2020 12 01 A Proposed Method for Locating of Leaky Areas in Water Supply Networks Based on Flow Hydraulic Grade Line 437 448 3386 10.22060/ajce.2019.16234.5575 EN Reza Moasheri Faculty of Civil, Water, and Environmental Engineering, Shahid Beheshti University, Tehran, Iran Mohammadreza Jalili-Ghazizadeh Faculty of Civil, Water, and Environmental Engineering, Shahid Beheshti University Journal Article 2019 02 15 Leaks in water supply networks cause problems such as water loss and contamination. Due to the difficulties of the current leak detection methods, some methods are recently being developed that use network field data (in the form of flow or pressure) and hydraulic simulation to determine the location of leaks. In this paper, a new method is proposed for locating the leaky areas in water supply networks, based on the results of field pressure measurements and investigating the hydraulic grade line. Suggestions on the number and arrangement of pressure meters in the network were also recommended. The obtained results for three scenarios in a looped water network with 30 junctions were presented. The results showed that this method can correctly identify the leak areas with no limitation on the number of simultaneous leaks in the network. On the other hand, this method is verifiable, unlike the most commonly leak analytical methods. In this methodology, if the number of field pressure meters increases, the reported leaky areas become smaller. As a scenario, by increasing the number of pressure meters from 3 to 4, the reported area gets halved. The proposed method can be utilized by operators of water distribution and transport networks. https://ajce.aut.ac.ir/article_3386_31ca0ca71184bbdb3de7b20a51e88e90.pdf

Amirkabir University of Technology AUT Journal of Civil Engineering 2588-2899 4 4 2020 12 01 Investigating the Effect of Particle Size on the Anisotropic Behavior of Saturated Sands, Using Hollow Cylindrical Torsional Shear Apparatus 449 472 3938 10.22060/ajce.2020.16390.5584 EN Alireza Mohammadi PhD Candidate, Civil Engineering Department, Urmia University, Urmia, Iran Hadi Bahadori Associate Professor, Civil Engineering Department, Urmia University, Urmia, Iran Journal Article 2019 05 20 <strong>The inherent anisotropic behavior of sands and the grain size effects are studied in this paper. A series of undrained torsional shear tests with constant inclination angle (α°) and intermediate </strong><strong>principal</strong><strong>stress ratio (b) was conducted by hollow cylindrical torsional apparatus (HCTA) on four types of sand. </strong><strong>This study furthers the knowledge on the dependency of steady states on anisotropy sands with different shape and size properties. In doing so, the direction of principal stress orientation is varied from 15° to 60°, for an intermediate principal stress ratio of 0.5 and 1.0 and constant initial confining pressure.</strong><strong>The results show that by increasing the particle sizes, the behavior of sands changes from contractive behavior to fully hardening and dilative behavior. Also, it observed that the effect of anisotropy in coarse grain sands is more than fine grain sands. In this study two-dimensional image analysis has been adapted to classify particle shape properties. These morphological characteristics were determined from the analysis of scanning electron microscope images and were defined as sphericity and roundness.</strong><strong>The results of the experiments on all four types of sand show that the anisotropy effects decrease by increasing the sphericity, but in coarse grain sands, the roundness of grains has no much effect on the behavior and anisotropy.</strong> https://ajce.aut.ac.ir/article_3938_74c407e263578d03d02c1123aa730b52.pdf

Amirkabir University of Technology AUT Journal of Civil Engineering 2588-2899 4 4 2020 12 01 Study of the Effect of Sensor Location on Sonic Echo/Impulse Response Testing in Timber Piles 473 486 3897 10.22060/ajce.2020.16552.5590 EN Saman Rashidyan Engineering Technology Department, University of North Texas Tang-tat Ng Civil Engineering Department, University of New Mexico Arup Maji Civil Engineering Department, University of New Mexico Journal Article 2019 06 12 <strong>Nondestructive Testing (NDT) methods have been utilized to assess the conditions of civil infrastructure in the past decades. Among various NDT methods, Sonic Echo / Impulse Response (SE/IR) is a versatile method to characterize unknown bridge foundations. Numerous numerical and experimental studies have been performed regarding the effect of influencing factors such as the pile-to-soil stiffness ratio, length-to-diameter ratio of the pile, presence of defects and anomalies near the pile head, striking method, and hammer type on the success of the SE/IR method. However, there is a lack of comprehensive study regarding the effect of the sensor location on the SE/IR testing results in timber piles. In the current study, challenges about the location of the sensor are investigated by conducting SE tests on bridges with known and unknown foundations. The results obtained from two accelerometers mounted on the side of the piles showed that the measured length of the piles was more consistent from the accelerometer mounted closer to the top of the pile. The success rate of the SE tests from the top accelerometer was 21.6% greater than the bottom accelerometer. The results of this study were confirmed by numerical simulations. Finally, the Impulse Response (IR) analysis was conducted to support the results. The conducted IR analysis showed that the success rate for the top accelerometer was greater than the bottom accelerometer. </strong> https://ajce.aut.ac.ir/article_3897_b957d47523c4e92a822cc38703a3bcc3.pdf

Amirkabir University of Technology AUT Journal of Civil Engineering 2588-2899 4 4 2020 12 01 Investigation on the Effect of Addition of Nano Alumina, Nano-silica, Nano Titania, and Mwcnts on Flexural and Compressive Strengths of Cement Mortar 487 504 3987 10.22060/ajce.2020.16811.5603 EN Behzad Akhondi Structural Engineer Ata Hojatkashani University faculty, Assistant Prof 0000-0003-4244-1552 Journal Article 2019 07 27 Being at the threshold of a revolution in nanotechnology, new advanced materials with higher knowledge contents, new functionalities, and improved performances are increasingly critical for industrial competitiveness and sustainable development. The current experimental research would focus on developing a new cement mortar material by partial replacement of cement with nanoparticles. Special concentration on controlling and presenting cement mortar flow rate according to ASTM C 1437, and also a comparison of mechanical performances of three Nanopowder and the Nanotube materials, could be considered as a distinctive and innovative part of this research. Such nanomaterials are the most useful ones with the most integrating effects. In this investigation, 60 prism specimens in four series each consisting of four specimens with nanomaterials and one benchmark, were prepared and molded-in triple-gang molds. Bending and compressive tests were conducted on the specimens at the age of 7, 28, and 90 days according to ASTM C348 and 349 standards. The results depicted that the best performances of investigated nanoparticles in increasing flexural and compressive strengths would occur in the early 7 days. Also, the diagrams indicated that specimens with 4% nano-silica provided up to 61% growth in 7 days compressive strength and 34% growth in 7 days flexural strength in comparison to average strengths of benchmark specimens. Thus, it can be recommended as the optimum mixing percentage of nanoparticles. Also, multi-walled carbon nanotubes, MWCNTs, showed acceptable performance in increasing the strength. Nano titania and nano alumina exhibited approximately neutral or negative effects on flexural and compressive strengths. The most important challenge in this study would be a dramatic decrease in the activity of nanoparticles in ages between 7 and 90 days. https://ajce.aut.ac.ir/article_3987_4f9c76cf97f84048c5990dd4ef842ea2.pdf

Amirkabir University of Technology AUT Journal of Civil Engineering 2588-2899 4 4 2020 12 01 Dynamic Analysis of Suspension Footbridges under Human-induced Vibrations and Near-field Earthquakes–Soti Ghat Bridge in Nepal 505 516 3681 10.22060/ajce.2019.16842.5604 EN Bahram Samadi Department of Civil Engineering, Faculty of Engineering, Urmia University, Urmia, Iran Gholamreza Zamani Ahari Department of Civil Engineering, Faculty of Engineering, Urmia University, Urmia, Iran 0000-0001-7228-8769 Journal Article 2019 07 28 <strong>Suspension footbridges are mainly under the influence of pedestrians' loads. In addition to the forces caused by pedestrians during the structure's lifetime, natural forces such as wind and earthquake also affect these structures. The effects of wind force on the suspension bridges are generally considered in the design process of the structure due to the high repetition of this phenomenon and lightweight of these structures but the earthquake forces are ignored due to the low probability of occurrence, low mass, and the high flexibility of these structures. This study aimed to investigate the dynamic behavior of suspension footbridges under the influence of the coincidence of pedestrians loading and earthquake forces. The final finding of this study was the impact of the earthquake on the suspension footbridges, which caused a change in the acceleration and forces of the bridge cables. It was found out that the simultaneity of human loading and earthquake forces increases the response of the lateral acceleration of the structure, and this increase is affected by the acceleration of earthquakes. Moreover, the lateral acceleration response of the structure changes during the pedestrians' movement, like the vertical acceleration response, but its amount is small at different speeds and does not cause any difficulty in operating the structure.</strong> https://ajce.aut.ac.ir/article_3681_9426c311e76888b3b2368150cd05f362.pdf

Amirkabir University of Technology AUT Journal of Civil Engineering 2588-2899 4 4 2020 12 01 Prediction of the Air Quality by Artificial Neural Network Using Instability Indices in the City of Tehran-Iran 517 528 3592 10.22060/ajce.2019.17018.5609 EN Razieh Farhadi Graduated Student, Environmental Sciences Department, Hakim Sabzevari University, Sabzevar, Iran Mojtaba Hadavifar Assistant Professor, Environmental Sciences Department, Hakim Sabzevari University, Sabzevar, Iran Mazaher Moeinaddini Assistant Professor, Environmental Sciences Department, University of Tehran, Tehran, Iran Mahmood Amintoosi Assistant Professor, Faculty of Mathematics and Computer Science, Hakim Sabzevari University, Sabzevar, Iran Journal Article 2019 09 07 <strong>Today, air pollution is a serious environmental problem becoming a global concern for human beings Air quality is influenced by emissions, meteorological parameters, and topography. The effect of these parameters can be predicted using statistical methods. In the current study, the data in the period of March 2012 to October 2013 are used. These data have been gathered from the stations of the Department of Environment and Air Quality Control Organization (Azadi and Sharif stations) in Tehran city. The main purpose was to predict the air quality of the next day and emissions of carbon monoxide and suspended particles under the influence of instability indices and meteorological parameters using the Artificial Neural Network. Results of the modeling process showed that the concentration of pollutants is strongly influenced by meteorological parameters. Also, prediction of the PM₁₀ concentration of the next day using meteorological parameters (RMSE=29.03, <em>R</em>=0.76), instability indices and meteorological parameters (RMSE=28.13, <em>R</em>=0.76) were better than those obtained for AQI predicted by meteorological parameters (RMSE=20.81, <em>R</em>=0.50) and instability indices and meteorological parameters (RMSE=19.23, <em>R</em>=0.47). In general, the predicted values of PM₁₀ and CO were better compared to AQI. It can be concluded that an artificial neural network couldn’t load the model properly for AQI compared to PM₁₀.</strong> https://ajce.aut.ac.ir/article_3592_69f357fcc8e6d119f3d95f33cedb5915.pdf

Amirkabir University of Technology AUT Journal of Civil Engineering 2588-2899 4 4 2020 12 01 Evaluation and Comparison of High Spatial Resolution Gridded Precipitation by TRMM, ERA5, and PERSIANN-CCS Datasets on the Upstream of the Maroon Basin, Iran 529 542 4034 10.22060/ajce.2020.17043.5610 EN Ali Gorjizade Ph.D. in Water Resources Engineering, Department of Hydrology and Water Resources, Faculty of Water Engineering, Shahid Chamran University of Ahvaz, Ahwaz, Iran Ali Mohammad Akhoond-Ali Professor, Department of Hydrology and Water Resources, Faculty of Water Engineering, Shahid Chamran University of Ahvaz, Ahwaz, Iran. Ali Shahbazi Head of the Office of Water and Environment Models of Khuzestan Water and Power Organization, Ahwaz Ali Moridi Assistant Professor of Faculty of Civil, Water and Environmental Sciences, Shahid Beheshti University, Tehran, Iran Journal Article 2019 09 13 <strong>Precipitation is a vital variable in hydrological studies which its applications and disciplines can be seen widely in water resources management. This parameter differs significantly over location and time; the lack of suitable data for precipitation results in difficulties in hydrological predictions. Therefore, the availability of this parameter in high spatial and temporal resolution is of great importance. Satellite precipitation estimation systems can provide information in areas where the data is not available. So, studying the accuracy of this type of data is very crucial. In this study, precipitation data from three satellite data sets, TRMM, ERA5, and PERSIANN-CCS, for the Idenak region, located in the southwestern part of Iran, (with four stations including Dehno, Ghale-Raeesi, Idenak, Margoon) from 2003 to 2014 was used and evaluated on the daily, monthly and annual basis. The results of this study indicate that the estimation of annual and monthly precipitation data obtained with the ERA5 model and TRMM has a better fit with the observation data in terms of precipitation values and spatial distribution, respectively. On the daily basis, the evaluation results show that at all stations, other than Margoon, the ERA5 model has been more appropriate concerning RMSE and CC values and provides better results. Moreover, according to the CSI values, in the detection of rainy and non-rainy days, the best detection is associated with the ERA5 model at all stations except the Ghale-Raeesi station while PERSIANN-CCS model has the higher ability at this station.</strong> https://ajce.aut.ac.ir/article_4034_7f5fc754c7af0a6370c9bf91314e79f4.pdf

Amirkabir University of Technology AUT Journal of Civil Engineering 2588-2899 4 4 2020 12 01 Evaluation of Protective Cavities Position on Decreasing Destructive Effects of Surface Blast on Buried Tunnels 543 556 3806 10.22060/ajce.2020.17101.5614 EN Haddi Hosseini Nassab Young Researchers and Elites Club , birjand branch ,Islamic azad university ,birjand , iran 0000-0001-7577-1801 Seyyed Mojtaba Movahedifar Department of civil, Neyshabur Branch, Islamic Azad University, Neyshabur, Iran. Journal Article 2019 09 24 In recent years, in the wake of growing military and terrorist threats especially against strategic and social buried structures, immunization of these structures against explosions becomes a major necessity. Therefore, it is crucial to study and use efficient methods to provide practical solutions to protect the key structures against advanced weapons and bombs. In this paper, the phenomenon of surface explosion and its impact on the tunnels, which are the most important buried structures, has been studied in full detail in a 3D environment. Additionally, evaluated the effect of depth, number, and location of the tunnel protective cavities in reducing destructive effects of the explosions on the tunnels in a 2D environment using nonlinear dynamic analysis in ANSYS-AUTODYN software. The results indicate that increasing the depth and number of the tunnel protective cavities are effective in reducing the destructive effects of the explosion on buried tunnels. As a key finding, the best location of the tunnel cavities was estimated in the range between the edges of the tunnel section and the edges of explosion charge. https://ajce.aut.ac.ir/article_3806_5e7264477cf9b6b237a0d254cf0324e2.pdf

Amirkabir University of Technology AUT Journal of Civil Engineering 2588-2899 4 4 2020 12 01 Ground Control Methods in High-Stress Ground Conditions in Civil and Mining Tunnels- Case Studies, and Benchmarking 557 578 3697 10.22060/ajce.2019.17235.5623 EN Masoud Ghorbani Department of Mining and Metallurgical Engineering, Amirkabir University of Technology, Tehran, Iran Kourosh Shahriar Department of Mining and Metallurgical Engineering, Amirkabir University of Technology, Tehran, Iran Mostafa Sharifzadeh Department of Mining &amp; Metallurgical Engineering, Curtin University, Western Australian School of Mines (WASM-MECE), Australia Journal Article 2019 10 17 <strong>Extreme ground behavior in high-stress rock masses such as rockburst prone and squeezing ground conditions are encountered in a range of underground projects both in civil and mining applications. Determining the most appropriate support system in such grounds is one of the major challenges for ground control engineers because there are many contributing factors to be considered, such as the rock mass parameters, the stress condition, the type and performance of the support systems, the condition of major geological structures and the size and geometry of the underground excavation. The main characteristics and support requirements of rockburst-prone and squeezing ground conditions are critically reviewed and characteristics of support functions are discussed. Different types of energy-absorbing rock bolts and other internal and external support elements applicable for ground support in rockburst-prone and squeezing grounds are introduced. Important differences in the choice and economics of ground support strategies in high-stress ground conditions between civil tunnels and mining excavations are discussed. Ground support benchmarking data and mitigation measures for mines and civil tunnels in burst-prone and squeezing grounds conditions are briefly presented by some examples in practice. The importance of the application of shotcrete shells with yielding elements in squeezing ground conditions has been presented in detail by a simplified Convergence Confinement Method (CCM) example.</strong> https://ajce.aut.ac.ir/article_3697_0b105cf1504c4e241fcc6d519ea962fb.pdf