Abbasi zargaleh, M.R.,
Mazloom, M.,
Jafari samimi, M.,
Ramesht, M.H. Structural Engineering and Mechanics (12254568)94(4)pp. 285-297
Concrete is the most diverse and widely used building material. The production of Portland cement is associated with the production of a large amount of carbon dioxide, which causes air pollution. It is inevitable to find an alternative material for Portland cement. Removal of cement is one of the greatest advantages of using geopolymer concrete. In this article, the results of tests on the fracture parameters of lightweight fly ash C class-based Geopolymer concrete (LWFCGC) as a material that has both advantages of lightness and use of green cement, are presented. These tests include three-point bending test on 49 beams with different activator to binder ratios. Also, compressive strength and tensile strength tests were performed on hardened concrete after 24 hours of processing at 80°C. In these experiments, three mix designs with 0.4, 0.5 and 0.6 activator to binder ratios were considered. By changing the activator to binder ratio from 0.6 to 0.4, compressive strength increased from 18.9 MPa to 28.4 MPa, fracture toughness improved from 19.65 MPa mm0.5 to 23.29 MPa mm0.5, total fracture energy (GF) increased from 59.20 N/m to 65.99 N/m, and the GF/Gf ratio decreased from 3.42 to 3.15. Copyright © 2025 Techno-Press, Ltd.
Materials Letters (18734979)390
Given the abundance, reduced cost, and environmental advantages associated with the utilization of ground granulated blast furnace slag (GGBFS) as a substitute for fly ash, this investigation examines the influence of GGBFS replacement levels of 5, 10, 15, 20, 25, and 30 % on the fracture behavior of lightweight fly ash-based geopolymer concrete (LWFCGC). Concrete specimens were produced using different proportions of GGBFS and fly ash and cured at 80 °C. Subsequently, they were subjected to compressive, tensile, and three-point bending tests. The results indicate that replacing fly ash with GGBFS significantly influences the mechanical properties of geopolymer concrete. Generally, increasing the GGBFS replacement percentage up to 20 % led to higher compressive strength and reduced porosity. However, increasing the GGBFS from 20 % to 30 % led to lower compressive strength. Increasing the replacement percentage from 0 % to 30 % resulted in an increase in fracture toughness from 16.73 to 27.49 MPa√mm and fracture energy from 54.9 to 156.06 N/m. In conclusion, this study shows that GGBFS can be a suitable substitute for fly ash in geopolymer concrete to some extent. By carefully selecting the ratio of GGBFS to fly ash, geopolymer concrete with desirable mechanical properties, fracture parameters, and durability can be achieved. © 2025 Elsevier B.V.
Tangtakabi a., ,
Ramesht, M.H.,
Pahlaviani a.g., A.G.,
Pourrostam t., Iranian Journal Of Science And Technology, Transactions Of Civil Engineering (22286160)48(3)pp. 1245-1260
The corrosion of reinforcement by chloride ions is a significant issue for reinforced concrete (RC) structures, which causes instability and loss of strength of the structure. In this study, the efficacy of various strategies for limiting the effects of chloride-induced corrosion on offshore RC structures was investigated experimentally through a series of experimental tests, including uniaxial compression test, half-cell potential test, and chloride ion penetration test. The tests have been conducted on concrete cube specimens with water/cement (w/c) ratios of 0.38, 0.45, and 0.50, which, for each w/c, the effect of normal cement (control specimens), engineered cementitious composite, self-compacting concrete (SCC), migration corrosion inhibitor (MCI), and microsilica (MS) were separately considered. The compressive strength of the specimens was obtained by uniaxial compression test at 7 and 28 days. Furthermore, to simulate wetting–drying cycles in marine environment, their corresponding 28 days cured specimens were exposed to the marine tidal zone at Technology and Durability Research Centre of Amir Kabir University, located at Bandar-e-Imam Khomeini, Iran, for 16 months and then were tested by half-cell potential and chloride ion penetration tests. The results revealed that, among all the specimens, the specimens with MCI and SCC achieved the highest and lowest compressive strength. In addition, the quantity of chloride ions that penetrate to the specimens indicates a low-risk corrosion for the specimens with MS and MCI and high-risk corrosion for the specimens with SCC. Moreover, it was concluded that using MCI was the most successful strategy for preventing reinforcement corrosion in maritime concrete structures. © The Author(s), under exclusive licence to Shiraz University 2023.
Baghi, H.,
Pahlaviani a.g., A.G.,
Ramesht, M.H.,
Marnani, J.A.,
Lavasani, A.M. Iranian Journal Of Science And Technology, Transactions Of Civil Engineering (22286160)47(4)pp. 2287-2293
Rain–wind-induced vibration in cable of cable-stayed bridges is currently a global concern. Since many parameters are effective in this phenomenon, it is difficult to repeat this phenomenon in the laboratory and its mechanism has not yet been well explained. In this paper, the phenomenon of rain–wind-induced vibration in cable of cable-stayed bridge model is studied by creating an artificial rain flow in a wind tunnel. The effect of the main factors of this phenomenon, yaw angle, on the vibration characteristics due to wind and rain for a simple cable has been studied in detail in the experiment. Reciprocal measures to reduce rain–wind-induced vibration by creating a spiral grooves on the cable have been studied. Then the effect of different grooves on rain–wind-induced vibration was tested. The results show that the presence of grooves on the cable reduces the rain–wind-induced vibration. When using these grooves in cables, care should be taken with the grooves distance, because in the average wind speed by increasing the yaw angle, the cable with a longer-distance grooves has less vibration than the cable with a short-distance grooves. With increasing wind speed, this vibration increases. © 2023, The Author(s), under exclusive licence to Shiraz University.
Geography and Natural Resources (1875371X)44(1)pp. 81-89
Abstract: The geomorphological and topographic landscapes of Yazd (Iran) are considered; their study is effective not only for the dispersal or selection of one or another human activity, but is also one of the effective factors in the formation of physical structures of spatial constructions. It is revealed that the analysis of urbanization can be influenced by the conceptualization of phenomenology, because from this point of view the basis of development of human settlements is primarily a spatial identity. According to the theory of “lakes of the fourth period of urban civilization in Iran,” lakes are considered components of urbanism in Iran, and they form its identity. This study is intended to complement other geomorphological studies in this area by focusing on Lake Yazd, located in the large Yazd-Meybod-Siyahkuh drainage basin. The work is based on a set of archaeological, geomorphological, sedimentological, space, and syntax studies, as well as on field data. It is shown that there are individual lakes in the Yazd-Meybod-Siyahkuh watershed, one of which is Lake Yazd. It is established that, during the glacial period, the lakes merged and ended up in the Siahkuh desert. It is concluded that large cities of Yazd province (Yazd, Meybod and Erdekan) owe their urbanism to the spatial identity, namely the existence of these lakes, while the spatial indeterminacy of smaller cities (Islamabad (Farasha), Taft, Hezrabad, and Mehriz) depends on the water–ice equilibrium line. © 2023, Pleiades Publishing, Ltd.
Hasannejad, A.,
Majrouhi sardroud, J.,
Shirzadi javid, A.A.,
Purrostam, T.,
Ramesht, M.H. Building Services Engineering Research and Technology (14770849)43(4)pp. 485-506
Design coordination and clash detection are the most common and appreciated applications of three-dimensional modeling (3D modeling). In some projects, millions of clashes are detected including a large number of irrelevant clashes. The purpose of this research is to determine the priority of resolving clashes before the construction phase. In this research, the results of Autodesk Navisworks have been used to improve the process of clash detection. Also, this study attempts to use the fuzzy-AHP for weighting criteria and then, by presenting a relationship, to provide a basis to prioritizing clashes for their resolution and, finally, for identifying irrelevant clashes. This method has been tested on a real project, and the comparison of the expert opinions and the proposed method showed that applying the proposed relationship can identify important and irrelevant clashes. Practical application: If clashes are not carefully detected in the design stage, project management components face a serious challenge. In this study, using the weight of clash elements and the degree of penetration of clash elements into each other, a logical and practical relationship is presented that improves the process of clash detection. © The Author(s) 2022.
Civil Engineering Infrastructures Journal (24236691)55(2)pp. 333-350
Deterioration due to corrosion is an important issue affecting the durability, strength, and sustainability of buildings and structures. Many cities are located in coastal areas and many reinforced concrete structures in these areas are exposed to chloride aggressive marine environments. Therefore, it is important to provide protection and offer appropriate repair methods of buildings vulnerable to the degrading effects of corrosion. The present study sets out to identify and evaluate the causes and extent of corrosion observed in Piers 11 and 12 in Imam Khomeini port, Iran. The microsilica is used to reduce corrosion. In order to achieve the above-mentioned goals, a number of experimental field tests were performed to determine the level of concrete condition in terms of reinforcement corrosion. Some tests were conducted to determine the conditions of concrete piers in terms of reinforcement corrosion. Then a reinforcement corrosion current density test is performed using a potentiostat involving a placement process; with different water-to-cement ratios and superplasticizers, the microsilica content was 5%, 10%, and 15%. Microsilica can serve as an alternative to cement and was measured according to the ASTM standards. Microsilica was exposed to aggressive conditions at different periods and a concrete compressive strength test was performed. The results showed that the compressive strength and corrosion resistance of the concrete increased for concrete mixture containing 10% microsilica with a water-to-cement ratio of 34% and a superplasticizer ratio of 6%. © University of Tehran 2022.
Mohammadkhanifard, H.R.,
Jalali moghadam, M.,
Zad, A.A.,
Ramesht, M.H. Marine Georesources and Geotechnology (1064119X)40(10)pp. 1205-1223
Many offshore and onshore platforms are constructed widely, especially in the energy supply sector. So far, various anchors with different shapes have been introduced for these applications to reinforce and stabilize the superstructures and related facilities. This study deals with the novel Expandable Multi-plate Mechanical Anchors (EMPMAs) and investigates their performance using physical modeling tests. Previous studies have focused on the behavior of single anchors, and there is no comprehensive experimental research on the multi-plate anchors, which is the subject of the present study. This research examines uplift capacity regarding the effect of five soil densities for loose, medium, and dense conditions and the vertical distance between two plate anchors from 0.5B to 2B. The obtained results were compared with the single plate anchor with equivalent areas. Based on the results, the highest bearing capacity is related to the EMPMA with an optimum distance of 1B in 80% relative density. In addition, by decreasing the distance between two plates, the relative density becomes a more dominant bearing capacity parameter. Furthermore, the Particle Image Velocimetry (PIV) method results are presented, and a new formula is proposed. Eventually, a comparative study is conducted between the results of PIV and an analytical formula. © 2021 Informa UK Limited, trading as Taylor & Francis Group.
European Journal of Futures Research (21952248)9(1)
Regional foresight is one of the regional planning approaches that increase the ability to deal with uncertainty and changes. This study aims to provide an overview of regional foresight studies and domain map to evaluate their merits and defects and direct future studies in this field. For this purpose, 111 papers related to regional foresight were identified at the “Web of Science” in the period 2000 to 2019 and used as the basis for further analysis. These papers have been reviewed in various aspects. In addition, the domain map of regional foresight and its intellectual bases was drawn based on co-citation analysis of these papers and their 4194 references. The domain map includes five main clusters of research areas or intellectual bases for regional foresight: normative forecasting, participation, foresight in policy and strategy, innovation systems, and multi-level governance. Finally, the merits and defects of regional foresight studies are evaluated based on research results and some suggestions are provided for future studies. © 2021, The Author(s).
Arpn Journal Of Engineering And Applied Sciences (24095656)12(8)pp. 2527-2532
The purpose of this study was to find, with the aid of ANSYS software, a formula for a vibration design of bridge piers that provides maximum convergence with experimental results, the effect of waves on fixed and floating platforms is an important consideration for designing of offshore structures, and thus several experimental and numerical models have recently been presented. In this paper, a numerical model was developed in an ANSYS program to simulate current wave interaction with a vertical cylinder acting as a platform leg. This involved using smooth-particle hydrodynamics method (SPH) for solving the hydrodynamics, as well as using the finite element method with regard to the structural aspect, according to an experimental sample. The required data were gathered through a library method called SPH, which is a Lagrangianun meshed method and is sufficiently accurate for free surface modeling in comparison with other Eulerian mesh-based methods. In this connection, the capacity of the method to calculate in-line and cross-flow forces on a cylinder was considered using different time solution algorithms. The results showed that the predictor-corrector algorithm led to the most accurate finding, compared to the Beeman, symplectic, and Verlet algorithms. Although vibration of cylinder have been investigated. © 2006-2017 Asian Research Publishing Network (ARPN).
Najafabadi, R.M.,
Ramesht, M.H.,
Ghazi, I.,
Khajedin, S.J.,
Saif, A.,
Nohegar, A.,
Mahdavi, A. Geomatics, Natural Hazards and Risk (19475713)7(1)pp. 85-100
In this paper, among multi-criteria models for complex decision-making and multiple-attribute models for assigning the most preferable choice, the technique for order preference by similarity ideal solution (TOPSIS) is implied. The main objective of this research is to identify potential natural hazards in Bandar Abbas city, Iran, using TOPSIS model, which is based on an analytical hierarchy process structure. A set of 12 relevant geomorphologic parameters, including earthquake frequency, distance from the earthquake epicentre, number of faults, flood, talus creep, landslide, land subsidence, tide, hurricane and tidal wave, dust storms with external source, wind erosion and sea level fluctuations are considered to quantify inputs of the model. The outputs of this study indicate that one region, among three assessed regions, has the maximum potential occurrence of natural hazards, while it has been urbanized at a greater rate compared to other regions. Furthermore, based on Delphi method, the earthquake frequency and the landslide are the most and the least dangerous phenomena, respectively. © 2014 Taylor & Francis.
Advances in Environmental Biology (19950756)8(25)pp. 35-39
Although the natural movements of the earth's crust have been noteworthy by the researchers from long time ago, but human power has had results in the Environmental, Widespread and profound changes which has been unbelievably appeared in different forms. As an example of such a process, it can be mentioned the slow sinking which are known as subsidence. Subsidence is one of the morphological phenomenon on which a part of earth's crust gradually is subsided. In other words, the regional subsidence of earth's surface includes the collapse toward the lower earth's surface which can be also included a little horizontal shift. It is said that some gaps are appeared by this subsidence which are called “SHAGH" in localism. The goal of this research which is from an empirical research in Esfahan University is more focus on the presented views which are about the mechanism and the reason of developing of the morphological results of the subsidence phenomenon. It was tried to explain the syllogistic comparison of Morphological levels of miniature model of groundwater aquifer with seams and gaps in the Yazd field depending on model behavior. The results showed that the subsidences which are result from the excessive water-laden from the groundwater aquifer are very little and cannot create a subsidence on the field surface. The superficial morphological change in minimized static model differs from the Yazd field and it shows the difference in the origin of this phenomenon © 2014 AENSI Publisher All rights reserved.
Procedia Engineering (18777058)54pp. 109-116
Persian Golf is known as one of the world's most aggressive environments in the field of corrosion in reinforced concrete. Presence of chloride in see water and especial weather condition including the high temperature and air humidity close to 100%, could lead to occurrence of severe corrosion in concrete structures and reduce their useful life and durability. Floating concrete docks well have their place in the Persian Gulf coasts. ShahidZakeri's port is one of these areas. This paper reviews the causes of the damage and corrosion in reinforced concrete structures and provides solutions to prevent occurring such defects in future products. © 2013 The Authors.
Rashidi, M.,
Ramesht, M.H.,
Zohary, M.,
Poursafa, P.,
Kelishadi, R.,
Rashidi, Z.,
Rouzbehani, R. Journal Of Research In Medical Sciences (17357136)18(12)pp. 1074-1079
Background: National Institute of Environmental Health Sciences (NIEHS) scientists shows that long-term exposure to air pollutants increases the risk of respiratory diseases such as allergies, asthma, chronic obstructive pulmonary disease, and lung cancer. Children and the elderly are particularly vulnerable to the health effects of ozone, fine particles, and other airborne toxicants. Air pollution factors are considered as one of the underlying causes of respiratory diseases. This study aimed to determine the association of respiratory diseases documented in medical records and air pollution (Map distribution) of accumulation in Isfahan province, Iran. By plotting the prevalence and spatial distribution maps, important differences from different points can be observed. Materials and Methods: The geographic information system (GIS), pollutant standards index (PSI) measurements, and remote Sensing (RS) technology were used after entering data in the mapping information table; spatial distribution was mapped and distribution of Geographical Epidemiology of Respiratory Diseases in Isfahan province (Iran) was determined in this case study from 2005 to 2009. Results: Space with tracing the distribution of respiratory diseases was scattered based on the distribution of air pollution in the points is an important part of this type of diseases in Isfahan province where air pollution was more abundant. Conclusion: The findings of this study emphasis on the importance of preventing the exposure to air pollution, and to control air pollution product industries, to improve work environmental health, and to increase the health professionals and public knowledge in this regard.
Journal of Isfahan Medical School (10277595)29(125)
Background: Cardiovascular disease is one of the most prevalent diseases in the world and it is expected to be the main cause of death by 2020. The aim of this study was providing geographical distribution map of the rate of death caused by cardiovascular diseases in the cities of Isfahan province, Iran, during 2005 to 2009. Methods: The rate of all the deaths in Isfahan province within 2005 to 2009 was provided. The collected data was used to find out the rate of deaths due to cardiovascular diseases and preparing geographical distribution maps. Then, by putting down the death rates for different sexes (men and women), the geographical distribution map for deaths with regards to cardiovascular diseases was drawn. Finding: Death rates due to cardiovascular problems were higher in main and central cities of the province. Death rate was higher in men than women. Conclusion: The observed model main and central cities is probably due to unsuitable diet, lack of motion, using new technologies and environmental pollutions including existence of some elements due to environmental pollutants such as industries, transportations of vehicles and air pollution, which are more prevalent in the main cities of the province. Also, due to existence of medical university centers and more health facilities in the main cities of the province, such as Isfahan, Najafabad, Borkhar and Maymeh, the registration system for deaths and diagnosing the causes of deaths are more accurate than other cities and towns of the province. The difference between two sexes could be due to in heritage, male hormones, some social factors, increasing fat around abdomen in men, exciting or even offensive behaviors in men, ignoring weight increase in men as compared to women and smoking.
Almodaresi S.A.,
Entezari M.,
Ramesht M.H.,
Boloor A.,
Almodaresi S.A.,
Entezari M.,
Ramesht, M.H.,
Boloor A. 2025 29th International Computer Conference, Computer Society of Iran, CSICC 2025pp. 236-240
This research attempts to zonate the Marbor River domain in the south of Semirom city with an area of 1438 km2 using multivariate statistical methods because of increasing instability of the slopes and landslide phenomena, to prevent it from human and financial damages. Therefore, by collecting required information on landslides dispersion in the region, landslide dispersion map is provided by preparing six informative layers which includes slope, aspect, lithology, land use, distance from the road, and precipitation rate. These layers were then intersected, whereby 1365 homogeneous land units were obtained. After that, the homogeneous units map was intersected with the landslide dispersion map. Finally, a 1365 × 22 matrix was prepared with values 0 and 1.0 denotes orders with landslide and 1 without landslide. Then, this matrix was included into SPSS application and linear regression and discriminate analysis methods were used to calculate and analyze the data. Afterwards, we analyzed the accuracy and precision of each method (P, QS). In conclusion, it is clear that linear regression method is more accurate and precise than the discriminate analyses. It is recommended, thus, to use the former in landslide hazard zonation. © 2010 IEEE.
NACE - International Corrosion Conference Series (03614409)1996
Computers provide a powerful opportunity fbr the development of teaching materials. They provide a rich interactive environment to stimulate and engage the student. The advent of computers with multimedia capabilities allows the constructor of teaching materials to show the student material from many sources; text, chart, audio, video, animal ion, simulation, sound or photographs. When these are combined with interactivity, a powerfitl learning enviroimient is created [1]. There is currently no CAL(Computer Aided Learning) or CBT(Computer Based Training) material available on the subject of corrosion and corrosion protection in concrete structures fbr ci\ ii engineering students. This paper will describe a Computer Aided Learning package intended to introduce students to the environmental degradation of concrete structures. © 1996 by NACE International.
Journal of Ferrocement (01251759)26(2)pp. 85-94
Ferrocement is a type of thin wall reinforced concrete construction where real composite action between the matrix phases and the reinforcement exists. This composite action results in excellent control of cracking, high tensile strength and durability [1]. This investigation is concerning with the experimental and theoretical behavior of ferrocement under tension. The effects of different arrangements of mesh reinforcement, with particular respect to the specimen thickness and mortar cover, on the cracking behavior and both first crack strength and ultimate strength were studied. The mechanical properties of the wire mesh and mortar which was used in this investigation were also studied. The results show that, under direct tension, the strength of ferrocement at first crack and ultimate load is not affected significantly by the arrangement of the reinforcement. However, specimens having reinforcement evenly distributed with minimum cover showed reduced crack widths and an increased number of small cracks at failure. The contribution of the tensile strength of the mortar and the specimen thickness on first crack strength is considered to be significant, while it can be considered negligible at ultimate strength.
Journal of Ferrocement (01251759)26(1)pp. 21-31
The aim of this paper is to review and compare various analytical procedures which have been developed to predict the ultimate moment of ferrocement under flexure. One such procedure has been used as the basis of the computer program FAOFERRS, which has then been used to compare predictions with experimental results for specimens having various mesh arrangements. An attempt is made to predict the ultimate moment for specimens reported by other investigators and the results are compared and discussed.
Journal of Ferrocement (01251759)25(2)pp. 105-113
Over the past decade, corrosion became a crucial problem on two counts: (a) it is expensive to repair and (b) it has widespread occurrence. The research evaluated the effects of corrosion on the properties and flexural behavior of ferrocement. Two series of specimens were tested. The first series were cast, placed in water and a suitable environment for 28 days, and then subjected to flexural test. The second series were placed in a weather simulator tank, with corrosive environmental conditions and after three months, were tested for flexure. From a careful examination of the results of the flexural tests it emerges that: 1. The presence of NaCl and temperature, as well as the prevalence of wet and dry conditions, have a considerable effect on the flexural behavior of ferrocement: it increases the brittleness of mortar, reduces the number of cracks and increases the crack width. 2. Slight increase in the first crack strength and maximum strength of specimens. 3. The effect of corrosion in reducing the strength of ferrocement specimens with ungalvanized wire meshes, is greater than its effect on specimens with galvanized wire meshes.
Journal of Ferrocement (01251759)23(4)pp. 289-299
Ferrocement has been increasingly used as a structural material which competes favorably with reinforced concrete and other building materials. The durability of ferrocement depends on several factors including the quality of ferrocement, mesh type, depth of cover over the mesh, the direction and magnitude of applied load(s) and its resistance to corrosion. Corrosion of mesh reinforcement in ferrocement is one of the important aspects which has not received sufficient attention from research workers. This paper presents the results of monitoring the corrosion performance of ferrocement specimens exposed to extremely aggressive conditions (6% NaCl solution at 60°C). Several parameters have been considered in this study, including type and arrangement of mesh reinforcement and depth of mortar cover over the meshes. Four methods were used for corrosion examination of the specimens; visual examination, corrosion potential, corrosion rate and microscopic examination.
