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| 1 | Optimization of cement-based grouts using chemical additives显示文摘Grout injection is used for sealing or strengthening the ground in order to prevent water entrance or any failure after excavation.There are many methods of grouting.Permeation grouting is one of the most common types in which the grout material is injected to the pore spaces of the ground.In grouting operations,the grout quality is important to achieve the best results.There are four main characteristics for a grout mixture including bleeding,setting time,strength,and viscosity.In this paper,we try to build some efficient grouting mixtures with different water to cement ratios considering these characteristics.The ingredients of grout mixtures built in this study are cement,water,bentonite,and some chemical additives such as sodium silicate,sodium carbonate,and triethanolamine(TEA).The grout mixtures are prepared for both of the sealing and strengthening purposes for a structural project.Effect of each abovementioned ingredient is profoundly investigated.Since each ingredient may have positive or negative aspect,an optimization of appropriate amount of each ingredient is determined.The optimization is based on 200 grout mixture samples with different percentages of ingredients.Finally,some of these grout mixtures are chosen for the introduced project.It should be mentioned that grouting operations depend on various factors such as pressure of injection,ground structure and grain size of soils.However,quality of a grout can be helpful to make an injection easier and reasonable.For example,during the injection,a wrong estimated setting time can destroy the injected grout by washing the grout or setting early which prevents grouting.This paper tries to show some tests in easy way to achieve a desirable sample of grout. | Mohammad Reza Azadi Ali Taghichian Ali Taheri | 2017 | Journal of Rock Mechanics and Geotechnical Engineering2017，9，4： | 8 |
| 2 | Evaluation of fatigue and rutting properties of asphalt binderand mastic modified by synthesized polyurethane显示文摘Fatigue and rutting phenomena are major distresses in asphalt pavements.Asphalt mixture properties are highly dependent upon the asphalt binder and the mastic behavior.The purpose of this study was to investigate the behavior of the asphalt binder and the mastic,modified by the synthesized polyurethane,at high and intermediate temperatures.The filler/asphalt binder ratio(by weight)was 1.0.The dynamic shear rheometer(DSR)was used to measure fatigue(G^(*)sinδ)and rutting(G^(*)/sinδ)parameters.In this study,the multiple stress creepandrecovery(MSCR)testwasalso utilizedto calculate the ruttingpotential of theasphalt binder and themastic.Parameters of the non-recoverable compliance(Jnr)and the percentage recovery(%)were evaluated at high temperatures.The obtained results indicated that the synthesizedpolyurethaneimproved the ruttingandfatigue properties.Therewasa significant correlation between the asphalt binder and the mastic in terms of the complex modulus(R^(2)=0.9958),rutting(R^(2)=0.9944),and the non-recoverable compliance(R^(2)=0.9707).For the fatigue parameter(R^(2)=0.9852),the complex modulus(R^(2)=0.9855),and the phase angle(R^(2)=0.8262),significant relationships were observed between the asphalt binder and mastic samples at intermediate temperatures.Overall,the chemical reaction between the filler and the asphalt binder could be effective in different behaviors of the mastic and asphalt binder.Therewasa 112%-164%increase in the G^(*)sinδparameter formastics,compared to that of the asphalt binder.The complex modulus was 6 times higher by adding the filler content. | Mana Motamedi Gholamali Shafabakhsh Mohammad Azadi | 2021 | Journal of Traffic and Transportation Engineering(English Edition)2021，8，6： | 3 |
| 3 | NVH analysis and improvement of a vehicle body structure using DOE method显示文摘 | Shahram Azadi Mohammad Azadi Farshad Zahedi | 2009 | Journal of Mechanical Science and Technology2009，，11： | 1 |
| 4 | NVH analysis and improvement of a vehicle body structure using DOE method显示文摘 | SHAHRAM Azadi MOHAMMAD Azadi FARSHAD Zahedi | 2009 | Journal of Mechanical Science and Technology2009，23，11： | 1 |
| 5 | NVH analysis and improvement of a vehicle body structure using DOE method 显示文摘 | Shahram Azadi Mohammad Azadi Farshad Zahedi | 2009 | Journal of Mechanical Science and Tech- nology2009，23，11： | 1 |
| 6 | Enhanced empirical models for predicting the drift capacity of less ductile RC columns with flexural,shear,or axial failure modes显示文摘Capacity of components subjected to earthquake actions is still a widely interesting research topic. Hence, developing precise tools for predicting drift capacities of reinforced concrete (RC) columns is of great interest. RC columns are not only frequently constructed, but also their composite behavior makes the capacity prediction a task faced with many uncertainties. In the current article, novel empirical approaches are presented for predicting flexural, shear and axial failure modes in RC columns. To this aim, an extensive experimental database was created by collecting outcomes of previously conducted experimental tests since 1964, which are available in the literature. It serves as the basis for deriving the equations for predicting the drift capacity of RC columns by different regression analyses (both linear with different orders and nonlinear). Furthermore, fragility curves are determined for comparing the obtained results with the experimental results and with previously proposed models, like the ones of ASCE/SEI41-13. It is demonstrated that the proposed equations predict drift capacities, which are in better agreement with experimental results than those computed by previously published models. In addition, the reliability of the proposed equations is higher from a probabilistic point of view. | Mohammad Reza AZADI KAKAVAND Reza ALLAHVIRDIZADEH | 2019 | Frontiers of Structural and Civil Engineering2019，13，5： | 1 |
| 7 | Analyses of the effect of seismic behavior of shallow tunnels in lique- fiable grounds 显示文摘 | Azadi M Mir Mohammad Hosseini S M | 2010 | Tunnelling and Underground Space Technology2010，25，5： | 1 |
| 8 | Identification of Pitch Dynamics of An Autonomous Underwater Vehicle Using Sensor Fusion显示文摘This paper presents a method for identification of the hydrodynamic coefficients of the dive plane of an autonomous underwater vehicle. The proposed identification method uses the governing equations of motion to estimate the coefficients of the linear damping, added mass and inertia, cross flow drag and control. Parts of data required by the proposed identification method are not measured by the onboard instruments. Hence, an optimal fusion algorithm is devised which estimates the required data accurately with a high sampling rate. To excite the dive plane dynamics and obtain the required measurements, diving maneuvers should be performed. Hence, a reliable controller with satisfactory performance and stability is needed. A cascaded controller is designed based on the coefficients obtained using a semi-empirical method and its robustness to the uncertainties is verified by the μ-analysis method. The performance and accuracy of the identification and fusion algorithms are investigated through 6-DOF numerical simulations of a realistic autonomous underwater vehicle. | Seid Farhad Abtahi Mohammad Mehdi Alishahi Ehsan Azadi Yazdi | 2019 | China Ocean Engineering2019，33，5： | 1 |
| 9 | The uplifting behavior of shallow tunnels within the liquefiable soils under cyclic loadings显示文摘 | M. Azadi S.M. Mir Mohammad Hosseini | 2009 | Tunnelling and Underground Space Technology incorporating Trenchless Technology Research2009，，2： | 1 |
| 10 | NVH analysis and improvement of a vehicle body structure using DOE method 显示文摘 | Shahram Azadi Mohammad Marshy Zahedi | 2009 | Journal of Mechanical Science and Technology2009，，11： | 1 |
| 11 | Determining the effect of Plantago major L. and Rosa damascene herbal ointment for bedsore healing显示文摘Background:Bedsores are damage or loss of skin integrity due to prolonged pressure which there are several ways to treat and prevent them.The aim of the study was to determine the effect of Plantago major L.and Rosa damascene herbal ointment for bedsore healing in hospitalized patients.Methods:This clinical trial study was accomplished with 100 patients divided into control(50 patients)and intervention(50 patients)groups.The control group had received routine treatment(dressing with Comfeel),but the intervention group only had received herbal ointment and then both groups were compared with each other through the pressure ulcer scale for healing(PUSH)tool.Results:The mean and standard deviation of recovery time in the Comfeel group was 27.40±12.467 and in the herbal ointment group was 21.57±12.695.In the pre-intervention evaluation,the mean and standard deviation of the PUSH score in the herbal ointment group was 10.44±0.323 while in the last evaluation in the same group it was 0.68±0.288 but in the Comfeel group,in the pre-intervention evaluation,the mean and standard deviation of the PUSH score was 10.68±0.317,while in the last evaluation it was 1.98±0.472.The highest frequency of bedsores in the study units was in the sacral region(49%)and the lowest frequency was in the sole of the foot with 1%.Conclusion:The results showed that Plantago major L.and Rosa damascene herbal ointment was effective in accelerating recovery time and wound healing. | Ashraf Salehi Mohammad Taheri Hamid Momeni Morteza Bakhshesh Davood Azadi Abdorrahim Absalan Mahdieh Azizi Amirhossein Latifi | 2022 | Aging Communications2022，4，4： | 0 |
| 12 | An enhanced damage plasticity model for predicting the cyclic behavior of plain concrete under multiaxial loading conditions显示文摘Some of the current concrete damage plasticity models in the literature employ a single damage variable for both the tension and compression regimes,while a few more advanced models employ two damage variables.Models with a single variable have an inherent dificulty in accounting for the damage accrued due to tensile and compressive actions in appropriately different manners,and their mutual dependencies.In the current models that adopt two damage variables,the independence of these damage variables during cyclic loading results in the failure to capture the effects of tensile damage on the compressive behavior of concrete and vice-versa.This study presents a cyclic model established by extending an existing monotonic constitutive model.The model describes the cyclic behavior of concrete under multiaxial loading conditions and considers the influence of tensile/compressive damage on the compressive/tensile response.The proposed model,dubbed the enhanced concrete damage plasticity model(ECDPM),is an extension of an existing model that combines the theories of classical plasticity and continuum damage mechanics.Unlike most prior studies on models in the same category,the performance of the proposed ECDPM is evaluated using experimental data on concrete specimens at the material level obtained under cyclic multiaxial loading conditions including uniaxial tension and confined compression.The performance of the model is observed to be satisfactory.Furthermore,the superiority of ECDPM over three previously proposed constitutive models is demonstrated through comparisons with the results of a uniaxial tension-compression test and a virtual test. | Mohammad Reza AZADI KAKAVAND Ertugrul TACIROGLU | 2020 | Frontiers of Structural and Civil Engineering2020，14，6： | 0 |
| 13 | Super gas wet and gas wet rock surface: State of the art evaluation through contact angle analysis显示文摘Recently,super gas wet and gas wet surfaces have been extensively attended in petroleum industry,as supported by the increasing number of publications in the last decade related to wettability alteration in gas condensate reservoirs.In many cases,contact angle measurement has been employed to assess the wettability alteration.Even though contact angle measurement seems to be a straightforward approach,there exist many misuses of this technique and consequently misinterpretation of the corresponding results.In this regard,a critical inspection of the most recent updated concepts and the intervening parameters in the contact angle based wettability evaluation of liquid-solid-gas systems could aid to provide some remediation to alleviate this problem.To this end,this work presents a survey on the accurate terms and rigorous protocols based on the community of surface science and chemistry.As a preliminary step,advancing,receding,static,and the most stable contact angle terminology are defined.The study is followed by the definition of the contact angle hysteresis effect.The application of surface free energy in the selection of the best gas wet agent is then analyzed.Afterward,the impact of the size-dependent behavior of drop on contact angle is discussed.Finally,a sessile drop experiment is explained to achieve the defined parameters.For future contributions to petroleum industry journals,like this journal,this work could offer an easy use of the conceptual framework for analyzing the results and comparative evaluations in chemical wettability modifier agents. | Mohammad Azadi Tabar Abolfazl Dehghan Monfared Flor Shayegh Farzad Barzegar Mohammad Hossein Ghazanfari | 2023 | Petroleum2023，9，1： | 0 |
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