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Showing 24 results for moghadas


Volume 0, Issue 0 (in press 2024)
Abstract

Moisture damage in asphalt mixtures poses significant challenges to infrastructure durability, necessitating accurate modeling for effective mitigation strategies due to the complex nature of moisture susceptibility. Current tests, such as those utilizing general indicators like the indirect tensile strength ratio, examine moisture susceptibility in asphalt mixtures. However, these tests incur substantial costs and require considerable time. Therefore, this study aims to develop moisture susceptibility prediction models using Multi-Gene Genetic Programming (MGGP). The research utilized four types of aggregates (two limestone and two granite types) and eight different Performance Grade (PG) bitumen types. The modified Lottman test method (AASHTO T283) was employed for moisture susceptibility assessment, with samples subjected to specific conditioning protocols including vacuum saturation (13-67 kPa absolute pressure), freeze-thaw cycles (-18°C for 16 hours), and hot water conditioning (60°C for 24 hours). Indirect tensile strength tests were conducted under controlled loading conditions (2 Hz frequency, 0.1s loading time, 0.4s rest period) at 25°C. The dataset comprised 34 samples and 11 variables to predict two key indicators: Inflection Stripping Point (ISP) and Stripping Slope (SS). The MGGP model demonstrated remarkable performance in predicting both ISP and SS, achieving R2 values of 0.981 and 0.974 for the test data, respectively. Several crucial parameters were analyzed, including the apparent film thickness (AFT) calculated using aggregate specific surface area, permeability measured through falling head test method (ASTM PS 129-01), and surface free energy components. The surface energy analysis incorporated both cohesive free energy (CFE) and adhesive free energy (AFE), with special attention to the acid-base theory components: Lifshitz-van der Waals (LW), Lewis acid (Γ+), and Lewis base (Γ-) components. For ISP prediction, the MGGP model identified key variables including the ratio of base to acid surface free energy (SFE), asphalt-water adhesion (ΓAsphalt-Water), cohesive free energy (CFE), adhesive free energy (AFE), permeability of asphalt mixture (PAM), asphalt film thickness (AFT), and degree of saturation (DS). The model for SS prediction emphasized the importance of ΓAsphalt-Water, aggregate-water adhesion (ΓAggregate-Water), wettability, specific surface area (SSA), PAM, and DS. The study employed various performance metrics to evaluate the MGGP models. For ISP predictions, the model achieved RMSE, MSE, and MAE values of 5.228, 27.337, and 3.843, respectively. For SS predictions, these values were 0.294, 0.086, and 0.231, respectively, indicating high accuracy and low error rates. These results surpass those of previous studies employing traditional Genetic Programming (GP) methods, highlighting the potential of MGGP as a powerful tool in modeling asphalt moisture susceptibility. The practical implications of this research are significant for improving asphalt mixture durability, reducing maintenance costs, and enhancing road safety. Future research could focus on validating the models across a broader range of asphalt mixtures and environmental conditions.
 

Volume 3, Issue 2 (summer 2022)
Abstract

Objectives: In recent years, the study of the concepts of resilience in different urban areas at different scales has attracted special attention, although the level and number of these studies are very small. Especially in the city of Tehran, which has entered the modern period from traditionl period ,the issue can be considered.
Methods: in the current research , first through library studies in the filed, items related to physical , environmental and social resilience in residential complexes were extracted.then, in these complexes, there are many modes of this type of resilience , which can be achieved by studying and classifying them to the degree of desirability of these complexes. the case study ,studied in this research is kOI No bonyad residential complex, because it is very popular despite the fact that it was built a long time ago .this research is done with interpretive method and in the form of qualitative and quantitative analysis. questionnaire, which was distributed among the residents of this complex to measure the level of physical -environmental and social resilience.
finding: from the findings of this research , it can be seen tha ASP foundation complex(ASP towers)has high level of resilience despite its high construction year.
conclusion: with the investigation done, the patterns used in the complex, which caused its durability , popularity and high resilience , can be used in the design of modern residential complexes so that we can have lasting buildings.

Volume 4, Issue 4 (Fall 2018)
Abstract

Aims: The aim of this study was to identify antibiotic resistant patterns and the prevalence rate of carbapenem resistant genes (imp-1, vim-2, kpc) in P. aeruginosa strains isolated from burn patients in Shahid Motahari Hospital of Tehran.
Materials & Methods: In this study, 63 P. aeruginosa strains were collected from infected patients.  Isolates were identified by biochemical tests and specific 16SrDNA PCR. Antibiotic susceptibility test was performed by standard Kirby-Bauer method according to the CLSI guidelines. The prevalence of imp-1, vim-2, and kpc genes were assessed by PCR.
Findings: All of the isolates were confirmed as P. aeruginosa by phenotypic tests and specific 16SrDNA PCR. Totally, 14 antibiotypes were identified. The highest resistance was observed against to tobramycin, gentamicin, amoxi-clavulanic acid, and cefoxitin (100%) and the most sensitivity was shown against colistin (100%). All of the isolates were multidrug resistant (MDR), 100 and 46% were positive for Extended Spectrum β-Lactamases (ESBL) and Metallo- β-Lactamases (MBLs) respectively. The imp-1 and kpc genes were not detected (0%), while vim-2 gene was present in all of the isolates.
Conclusion: In the current study, the high resistance rate to antibiotics might be due to their overuse for burn patients as a prophylactic or therapeutic agents. Colistin is considered a drug of choice for the treatment of wounds infected by P. aeruginosa in burn patients. In this study, the majority of P. aeruginosa isolates belonged to Antibiotype 1 and possess carbapenemase vim-2. Therefore, to stop this resistance transmission, the prevention and control are apparently essential.


Volume 5, Issue 7 (9-2020)
Abstract

Comparative and linguistic study of invitations in the cultural context of Iran and Iraq Involvements as linguistic genre are regarded as sociological data and are considered as an indicator of the relationship between social phenomena. By examining invitations of a particular time period, discourses derived from phenomena Social that period. This comparative study, which is based on the analysis of the genre and the critical analysis of discourse, attempts to explore the structure of wedding cards written in Arabic and Persian languages, and the role of social and cultural values. In its formulation. Familiarity with the social approaches of two different cultures, studying the impact of social and cultural factors on invitations, comparing the structure of invitations and explaining the impact of social phenomena on linguistic phenomena are among the most important goals of this research. Since this research examines the social approaches of the two countries and increases the level of recognition of different cultures, it seems necessary to do so. The results of the study show that the importance of the diversity of text and forms of wedding cards in Iran is more significant than in Iraq, with the title acquired in Iraq becoming more and more important, religious and patriarchal categories have a crucial role in the structure of wedding cards in There are two cultures, with the difference that the role of these two categories in the wedding cards of Arab countries is more colorful than Iran.

Volume 7, Issue 4 (2017 2018)
Abstract

Iran has an arid climate which characterized by long, hot, dry summers and short, cool winters. Therefore, sunlight and its heating effects were important factors of Iranian architecture and gardens structural design. Textures and shapes were selected by architects to harness the light and supply a shadow in the summer.
Water is very important in this climate, both in the architectural design and longevity of gardens. In addition to water, the plants in Iran had been particularly significant. In ancient civilization of Iran, plants have had special position. Supernatural powers that had been in trees such as life-giving, young giving, productivity and Immortality made them sacred for Ancient Iranian people. However, attending to supernatural power of plants was the importance reason that people regarded to plants and made some symbols such as “Life Tree” has income. In Zoroastrian religion books, more values have said about Supernatural cost of plants. Plants have a special value in Zoroastrian Fire Temples, religious ceremony and routine life. Therefore, garden and gardening were sacred for Iranian. The term Zoroastrianism is, in general usage, essentially synonymous with Mazdaism, have discovered dependent on Achaemenids Empire (559–330 BC) and there were in Pasargad. In the Islam tradition the garden as Paradise is, perhaps, even stronger, since the Quran (the central religious text of Islam) describes Heaven as a garden. Islam was spread to the Persians, and reciprocally the Muslims adopted the Persian style of garden. Therefore garden has been invaluable to Iranians. Persian Garden includes some types which one them is Garden City.
Isfahan as the Capital of Safavid Dynasty has designed as a big garden according garden city model. Therefore, some solutions have used in urban design regarding Isfahan's arid climate. Safavid government followed the realization of cities ideal that rooted in Islamic beliefs and opinions. The investigations in historical perspective of Safavid cities indicates the importance of cities as the place for presence of symbols and signs. The Symbols which has remind as the ideological concepts, power of dominating government and also getting identity to the city.
During the history of Safavid urban design, there were some direct and wide streets (Charbagh) which were the main factors of development and improvement of cities among urban functional and symbolic elements. In historical background of Isfahan garden city is pointed to construction of street (Charbagh) which has attracted the European tourists attention and it will investigate in this article.
Initial section of this article is allocated to explain about historical background of Isfahan city in Safavid era and also Charbagh Street. Then this paper with emphasis on some historical documents and analytical studies, compares the Isfahan Charbagh Street with its similar sample in France (Champs-Elysées Street). The conclusion of this article indicates the similarity of Isfahan Charbagh Street and Champs-Elysées Street in some skeletal specifications and the way of formation. French Boulevards were constructed after Isfahan Charbagh in terms of time and they were formed after publishing itineraries and pictures of tourists from this place in Europe .

Volume 9, Issue 2 (6-2017)
Abstract

This research attempts to explain the democratic consolidation in Iran and Turkey. To this end, the following research question is proposed: why Iran has stopped in transition phase and Turkey has moved toward consolidation.The theoretical model is extracted from the theories of democratization, consolidation of democracy, civil society and political parties. Based on the theoritical model, the hyphothesis of article is formulated: the institionalized political parties are the necessary condition for democratic consolidation. The institionalized political parties would reduce non-civilian actors and activities and is fertile ground to spreading democratic values such as toleration, moderation, trust and cooperation. The method in this article is historical comparative study. According to the emprical evidence, difference between the level of political parties’ institutionalization in Iran and Turkey has produced different results in terms of democratic consolidation in the two countries. In Turkey, since early 2000s, especially after the victory of the Justice and Development Party in the 2002 parliamentary elections, moving towards democratic consolidation phase has facilated, whereas the weakness of political parties’ institutionalization has caused democratization in Iran to cease in transition zone.

 

Volume 9, Issue 3 (9-2023)
Abstract

­­­The biodiversity of the Noctuidae, an economically important family of Noctuoidea which include major crop pests, is becoming well-identified nowadays in Iran due to the increased number of faunal expeditions. The two large subfamilies of Noctuidae namely Xyleninae Guenée, 1837 and Noctuinae Latreille, 1809 comprise the majority of Iran's noctuid moth fauna. Two species, Leucochlaena hoerhammeri (Wagner, 1931) and Dichagyris (Stenosomidesmansoura (Chrétien, 1911) members of Xyleninae and Noctuinae subfamilies, respectively, are recorded from Iran for the first time. This is also the first record of the subgenus Stenosomides Strand, 1942 from Iran. Both the external and genital characteristics of the newly recorded species are presented together with illustrations of the adults and their genitalia.

Volume 12, Issue 5 (1-2013)
Abstract

Automotive crankshafts are subjected to fluctuating torques due to periodic strokes in the cylinder. The gas-forces and inertial-forces due to the reciprocating masses will contribute to the excitation forces on the crankshaft system. The forces cause alternative torque on the crankshaft and cause vibration on the motor which cause noise and shake in the vehicle. Therefore, it’s necessary that was determined crankshaft dynamic behaviour. Although most physical structures are continuous, their behaviour can usually be represented by a discrete parameter model. In this paper, torsional vibration was determined with theoretical, analytical and experimental analysis on the Peugeot and Renault vehicle. For Solution of theoretical analysis, was used of B.I.C.E.R.A formula [1] and natural frequency for analytical analysis obtained with ANSYS software. Then, theoretical and analytical procedure compared with the experimental model, to obtain optimization model and with the best model, influence of torsional vibration was determined on the engine speed.

Volume 13, Issue 4 (1-2023)
Abstract

 Multiple sclerosis (MS) is one of the most common autoimmune diseases in Iran and the world. To date, many drugs have been developed to control the progression of MS as a chronic inflammatory disease of the central nervous system. Rituximab is a chimeric mouse-human monoclonal antibody that binds to the CD20 receptor on the surface of B cells and induces apoptosis. Today, Numerous studies have confirmed the increasing role of non-coding RNAs in regulating the expression of genes and molecular processes, including apoptosis. Furthermore, bioinformatic analysis results indicate that TUG1 LncRNA is differentially expressed in MS patients. Thus, In the present study the possible role of TUG1 in regulating rituximab mechanism of action and apoptosis induction was experimentally investigated. To do this, specific DNAzyme against TUG1 was designed and transfected into Raji cells in the presence or absence of the drug. After transfection, RNA extraction and cDNA synthesis were performed. Then, the expression of target genes was examined by Real-Time PCR technique. The results showed an increase in CD20 expression and a decrease in SMAD2 expression levels. Furthermore, decreased TUG1 gene expression led to an increase in apoptosis and cell accumulation in the G1 phase. It seems that TUG1 expression level can play a significant role in CD20 expression in B cells and therefore on the therapeutic efficacy of rituximab.
 

Volume 16, Issue 8 (10-2016)
Abstract

In this paper, the performance of a single-axis attitude control with pulse-width pulse-frequency (PWPF) modulation is enhanced using a modified proportional-integral-derivative (PID) controller for a rigid satellite with on-off thruster actuators. For this purpose, the well-known observer-based PID approach is utilized. The on-off thruster actuator is modeled with a constant delay followed by a second-order binomial transfer function. The modulator update frequency is limited to 40 Hz as an input to the on-off thruster actuators. In this study, the design criteria of pointing accuracy, overshoot of the attitude response, fuel consumption, and the number of thruster firings are considered for a step external disturbance (with different values). The parameters of the observer-based PID controller are tuned using parametric search method. Simulation results show that the fuel consumption and settling time of the observer-based approach are considerably decreased with respect to those of PID controller with PWPF modulator. Moreover, the overshoot of the observer-based approach is omitted. Finally, the robustness of the observer-based modified PID controller is investigated in presence of uncertainties in satellite moment of inertia and thrust level of on-off actuators.

Volume 16, Issue 91 (September 2019)
Abstract

In this study, Lactobacillus plantarum bacteria were used for production of blackberry and celery probiotic beverages in two concentrations of 1 and 2% at ambient temperature and refrigerator. The tests included determination of pH, titratable acidity, counting viability of target microorganisms and sensory evaluation. The results showed that with passing time and growth of target bacteria in blackberry and celery beverages, pH was significantly dropped. The results of counting viability showed that among all samples, blackberry beverage containing 2% of the bacteria stored in the refrigerator after 28 days had the highest viability of microorganisms, which is 8.25×107 CFU/ml as well as celery beverage containing 2% of probiotic bacteria stored in the refrigerator after 21 days had the highest viability of microorganisms, 4.02×107 CFU/ml, than the other samples, of which two samples were in these conditions Still called by the name of probiotic beverage. The sensory evaluation also showed that the sensory properties of the BLR1 (Blackberry beverage with 1% bacteria in refrigerator), BLR2 (Blackberry beverage with 2% bacteria in refrigerator) and CLR1 (Celery beverage with 2% bacteria in refrigerator) with their evidence samples also scored without significant difference, but in general, samples of celery beverage scored more than blackberry beverage. From the findings, it can be concluded that blackberry and celery beverages were suitable raw material for growth of Lactobacillus plantarum.
 

Volume 17, Issue 12 (2-2018)
Abstract

In this research, High Order Expansions method implementation in order to obtain an optimal solution for an unmanned aerial vehicle continuous maneuver problem is studied. The main goal of this research, is to describe a specific approach to solve nonlinear optimal control problems using series expansions and algebraic matrix Riccati equation in order to obtain solutions with better performance. Based on this, the state feedback control with different powers is used for optimal commands calculations. Clearly, the control command would be high order and closed-loop; it has been shown it results in a superior performance in smooth nonlinear problems. In this research, in addition to the implementation of High Order Expansions method and its usage, a different approach of dealing with optimal control problem based on this method has been given. Continuous maneuver of an unmanned aerial vehicle problem is solved for investigating the performance of the proposed method. In this example, the High Order Expansions up to and including the third order are used and two different flight scenarios are simulated. By investigating the result of the solution to this problem, the superior performance of the third order optimal command with respect to the first order is illustrated.

Volume 18, Issue 5 (9-2016)
Abstract

The life history and predation rate were determined for all stages of female and male of Phytoseiulus persimilis Athias-Henriot fed on the eggs of Tetranychus urticae Koch ˗ as the preferred prey-stage ˗ on rose (cv ‘blarodje’) leaf discs under laboratory conditions at 25±1°C, 75±5% RH, and 16 L: 8 D hour photoperiod. According to the age-stage, two-sex life table model, the intrinsic rate of increase (r), finite rate of increase (λ), net Reproductive rate (R0), Gross Reproductive Rate (GRR), and mean generation Time (T) were 0.296 d-1, 1.345 d-1, 33.48 offspring, 53.87 offspring and 11.83 d, respectively. Moreover, average number of T. urticae eggs consumed by different stages/sexes of P. persimilis was calculated based on the age-stage, two-sex life table model and indicated that the consumption rates increased from nymph to adult in both sexes. Also, our results showed that females consumed prey eggs 11 times more than males. The net predation rate (C0) and transformation rate from prey population to predator offspring (Qp) were 363.54 mite eggs and 10.86, respectively. The results showed that P. persimilis can successfully survive and reproduce on T. urticae eggs on rose.

Volume 19, Issue 11 (November 2019)
Abstract

Beams are the basic geometries in engineering and many engineering issues are simplified as a beam problem. In this paper, the dynamics and vibration analysis of composite Timoshenko beam made of epoxy graphite layers with two piezoelectric layers on both sides have been investigated. Extraction of motion equations has been conducted based on the first-order shear deformation beam theory using the Hamilton principle. The partial differential equations were converted to the first-order coupled differential equations and then they were solved by fourth-order Runge–Kutta method. The effect of piezoelectric parameters on the vibrational and dynamic response of the beam has been investigated. The results show that the natural frequency of the beam decreases with increasing the length of the neam. Among piezoelectric parameters, the parameter of C11 has a lower effect than the effective transverse coefficient of e31 in the frequency response. As the ratio of the length of the beam is lower than the thickness, the effect of C11 will be greater on the natural frequency. The effect of the other piezoelectric parameters in the frequency response has also been evaluated very small relative to these two parameters.


Volume 19, Issue 11 (November 2019)
Abstract

In this research, an innovative approach has been proposed to the calculation of high order sensitivities and designing its guidance commands for an unmanned aerial vehicle landing strategy design. This method, which is called vectorised high order method, has been developed based on high order expansions method and its implementation using matrix-based mathematical calculations. In this research, a method is presented to design and extract the acceleration commands for landing maneuvers, by combining the vectorised high order expansions method and optimal control theory. Accordingly, the sensitivity variables for the given problem are calculated up to the 6th term and then the reference trajectory and acceleration command in the simulations are updated based on the initial deviations. In order to performance evaluation of the proposed method, 3 landing scenarios with the different initial deviations have been considered and the results of simulation of the proposed guidance law have been presented.


Volume 20, Issue 3 (5-2018)
Abstract

Prey suppression by predators depends on effective predator: prey release ratios. The effectiveness of Phytoseiulus persimilis Athias-Henriot and Typhlodromus bagdasarjani Wainstein and Arutunjan was evaluated at different predator: prey release ratios for suppression of Tetranychus urticae Koch populations on cucumber plants in the microcosm condition based on three experiments. In the first experiment, 7 days after T. urticae releases, the most reduction in the different stages (densities) of T. urticae and the most increase in both P. persimilis and T. bagdasarjani were observed in predator: prey release ratio of 1:4 followed by ratios of 1:10 and 1:20. In the second experiment, one day after T. urticae release at predator: prey release ratio of 1:4, there was no significant difference between predators effect on the decline of T. urticae stages (densities). In this case, more T. bagdasarjani at all stages was observed on the plants in comparison with P. persimilis. According to the third experiment, 7 days after T. urticae release, there was no significant difference between predator: prey ratio of 1:4 of P. persimilis and 1:2 of T. bagdasarjani on T. urticae suppression. In this case, more P. persimilis was observed on plants in comparison with T. bagdasarjani. Our study demonstrates that the most suppression of T. urticae populations occurred in predator: prey ratio of 1:4 for both predators. Based on our findings, we suggest that P. persimilis and T. bagdasarjani can be released at a ratio of 1:4 for successful control of T. urticae on cucumber.

Volume 20, Issue 8 (August 2020)
Abstract

Research on DNA is particularly important in the diagnosis, control, and treatment of many diseases, including cancer. Today, the use of digital droplet polymerase chain reaction (ddPCR) for different DNA tests has attracted much researchers’ attention. A large number of micron-sized droplets are required to perform ddPCR. In the present study, a ddPCR system was designed, fabricated, and evaluated using a microfluidic chip. The system comprises a microfluidic chip for droplet generation and a thermal cycling device needed for PCR. The droplet generation in the microchip was simulated in 3D. The simulation results were validated. The average error is about 5% in the radius of the droplets. The constructed thermal cycling device controls the chip temperature with a precision of ±1.5°C. The in-chip PCR process was successfully performed by applying 25 heat cycles. The fluorescent property was observed in most droplets that prove the thermal cycling device can provide the conditions for DNA proliferation in the laboratory. The images were processed, and different levels of fluorescent light were identified in the droplets. The coefficient of variation of the selected droplets is 2.5%, which gives a good accuracy compared to the acceptable amount for these types of systems (less than 8%). The results obtained from this fully native device can be used in many fields, including cancer detection, examination of malignant tissue, and evaluation of the success in tissue surgery.


Volume 22, Issue 4 (7-2022)
Abstract

One of the main objectives of infrastructure managers is the timely and rapid operation of airports and freeways. A goal that is challenging when utilizing concrete pavements, due to their different behavior during the initial stages of implementation. This research aims to improve the mechanical characteristics of concrete pavements and increase their durability against the combined effects of the freeze-thaw cycle and surface desalination, especially during early ages. This paper examines the use of cementitious material in combination with hydrated lime, metakaolin, and zeolite to remove the hurdles to the early operability of concrete pavements. To this end, micro-structural studies have been performed using XRD and SEM analysis and comparisons in two states of water processing and exposure to freeze-thaw cycle. During which replacing cement with zeolite and metakaolin in calcareous concrete resulted in reduced porosity and homogeneous density with the formation of CSH in the concrete structure. 
Accordingly, improvements in the mechanical properties and durability of concrete pavements against the combined effects of freeze-thaw cycle and surface desalination were studied and analyzed in four mixtures of Control Concrete (CC), 15% lime (CL), 15% lime, and 15% Metakaolin (CLM) and 15% lime and 15% Zeolite (CLZ). It was noted that at age of 7 days the CLM, CL, and CLZ samples showed an increase of 20%, 32%, and 48% respectively compared to the CC sample. This increase continued throughout the study. During the freeze-thaw test and after 55 cycles the CLM and CLZ samples always exhibited lower degradation and showed a weight loss of 48.7% and 75.2% less than the CC sample. In addition, as per the results of the capillary absorption test the CLM and CLZ mixtures had at lower ages had less permeability than the CC mixture and this behavior continued with better performance at older ages.
 
 Also, the results of flexural strength indicate the positive effect of additives in all samples over time, and at 28 days, the CL, CLM, and CLZ samples increased flexural strength by 39%, 42%, and 57% respectively in comparison to the CC sample. The positive effect of hydrated lime due to its high paste property in increasing the flexural strength of mixtures containing metakaolin and zeolite is quite evident and has increased the mechanical properties at all ages of the samples, but has weakened the durability performance compared to the control sample. This issue has been addressed in composite mixtures containing lime with metakaolin or zeolite, and the results of durability tests indicate a significant improvement in both pozzolans, especially in the zeolite. It can therefore be concluded that with improving mechanical characteristics and durability of CLM and CLZ mixtures, utilizing metakaolin and zeolite in concrete containing hydrated lime is a suitable solution to eliminate the challenges of early usage in concrete pavements.

Volume 22, Issue 4 (7-2022)
Abstract

Road pavements are one of the most important assets of any country, and tremendous amounts of budgets are allocated for their maintenance every year. Unexpected distresses in asphalt pavement cause many financial losses. Winter maintenance of roads and infrastructures and the study of the effects of anti-icers and deicers on the asphalt pavements have always been of interest to researchers, departments, and agencies in the field of roads and transportation. As a contribution to this task, the present study was conducted to evaluate the effect of Zycotherm on the fracture behavior of asphalt mixtures in the presence of moisture and deicers. In order to achieve the research objectives, PG58-22 bitumen and siliceous materials were used to prepare the asphalt mixture and also Zycotherm was used to modify the asphalt binder. Data were collected by testing on laboratory samples. The asphalt mixture samples were conditioned in the presence of distilled water and solutions of brine, calcium magnesium acetate, and potassium acetate in their normal concentration for 96 hours at 60°C. Then, the fracture toughness of the specimens at low temperatures (K1c) and the critical strain energy release rate (Jc) at intermediate temperatures were measured by performing a semi-circular bending test (SCB). The results showed that simulation of low-temperature environmental conditions in the vicinity of distilled water and all deicers reduces the fracture toughness of asphalt mixtures compared to the dry sample. Brine solution has the most negative effect among all the deicers and reduces the K1c parameter by approximately 30%. On the other hand, Zycotherm maintains the fracture toughness of the asphalt mixture at low temperatures in the vicinity of distilled water and deicers at an almost constant level and recovers about 70% of the lost fracture strength of the sample conditioned in the brine solution. The effect of Zycotherm at intermediate temperature is different and causes the softening of bitumen and the reduction of the critical fracture force and the reduction of the critical strain energy release rate. This reduction is 34% and 32% for the dry sample and the specimen in the presence of brine solution, and 23% and 12% for the samples in the presence of calcium magnesium acetate and potassium acetate, respectively, compared to the sample made of neat bitumen. Also, samples in the vicinity of distilled water and potassium acetate solution showed no significant change in their critical strain energy release rate compared to samples in dry conditions. Visual inspection also revealed that calcium magnesium acetate causes additional stress and cracking in the samples. In a general summary and based on the obtained results, Zycotherm has a positive effect on the fracture toughness of the asphalt mixture at low temperatures but reduces the Jc parameter at intermediate temperatures. All specimens have the minimum critical strain energy release rate recommended by ASTM D-8044 at intermediate temperatures. Potassium acetate has no effect on the fracture toughness of asphalt mixtures at low and medium temperatures and can be an appropriate alternative in comparison with other deicers in winter road maintenance.

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