توجه: محتویات این صفحه به صورت خودکار پردازش شده و مقاله‌های نویسندگانی با تشابه اسمی، همگی در بخش یکسان نمایش داده می‌شوند.
۱EVALUATION OF EFFECTIVE PARAMETERS ON VIBRATIONS INDUCED BY PILE DRIVING WITH FINITE ELEMENT METHOD
نویسنده(ها): ، ،
اطلاعات انتشار: ششمین کنفرانس بین المللی زلزله شناسی و مهندسی زلزله، سال
تعداد صفحات: ۸
nowadays , using deep foundations is needed more than ever due to increasing population and lack of suitable soils pile driving is oldest and one of the most reliable methods of pile installations unfortunately environmental problems and vibrations induced by pile driving have limited using the pile driving in urban areas.

۲Uncertainty Modeling in Geotechnical Engineering Using Rough Set Theory
نویسنده(ها): ،
اطلاعات انتشار: ششمین کنفرانس بین المللی زلزله شناسی و مهندسی زلزله، سال
تعداد صفحات: ۸
Civil engineers need to analyze and model uncertainty in many fields, such as the development of construction codes, analysis of natural hazards, decision making in infrastructure maintenance expenditure. Problems that are commonly encountered by geotechnical engineering require decision making under conditions of uncertainty, lack of knowledge, and ignorance. The lack of knowledge and ignorance can be related to the definition of a problem, the alternative solution methodologies and their results, and the nature of the solution outcomes. In this paper a new approach is introduced based on the Rough Set mathematical theory presented by Pawlak (1991), a well–known mathematician, this procedure is used for reasoning under uncertainties. An adequate understanding of the input parameters variability influence on the engineering computations output requires that the uncertainty itself is captured in mathematical terms. This paper is therefore intended to better prepare future analysts, how to model and analyze uncertainty, and how to select appropriate analytical tools for a particular problem in geotechnical and earthquake engineering.<\div>

۳Geotechnical Investigations Optimization Using Rough Set Theory
نویسنده(ها): ، ،
اطلاعات انتشار: نهمین کنگره بین المللی مهندسی عمران، سال
تعداد صفحات: ۸
Geotechnical investigations are performed to evaluate geologic, seismologic, and soils conditions that affect the safety, cost effectiveness, design, and execution of a proposed engineering project. Currently, advanced methods have been developed for making the best decision in site selection to prevent unnecessary costs which are very important in large construction projects. In this paper a new approach has been developed based on the Rough Set theory that was presented by Pawlak (1991), a well–known mathematician. The results of practical studies indicate that using this method for projects can reduce costs, by preventing occurrence of hazard events due to geotechnical uncertainties. The rough set method is a method to deal with geotechnical uncertainties. The Results of Rough Set theory not only provide a baseline for decision making but also insights to the problem of concern. Using simple geotechnical problems we demonstrate that Rough set theory may supply a useful means for decision making under uncertainties<\div>

۴A Study on the Effects of CNT’s on Hot Mix Asphalt Marshal–Parameters
نویسنده(ها): ، ، ،
اطلاعات انتشار: هفتمین کنفرانس بین المللی پیشرفتهای علوم و تکنولوژی، سال
تعداد صفحات: ۹
Asphalt pavement is considered as the national capital and every year, much of the country’s development budget is spent on road maintenance and improvement of the engineering characteristics of pavements. Therefore, new plans must be used to improve quality and to increase productivity and durability of conventional asphalt pavements. In this investigation, it has been attempted to promote technical characteristics of asphalt mixture using carbon nanotubes as an additive material for bitumen. So far, there has been little discussion about carbon fibber modified asphalt concrete but dimension of discussed fibbers have been in range of micro not nano. In this article, marshal test parameters of hot mix asphalt, modified with carbon nanotubes, are investigated and compared to conventional asphalt mix. Wet and dry process methods are most practical ways of mixing CNF in AC. It was decided that the best method to adopt for this investigation was dry process. In this study marshal test parameters of modified asphalt by 0.1, 0.5, and 1% carbon nanotube content in bitumen was evaluated considering marshal test, then results were compared to conventional asphalt mix. Obtained results shown, using carbon nanotube improves hot mix asphalt marshal stability and decreases marshal flow.<\div>

۵Experimental Investigation of Nano Zinc Oxide Effect on Creep Compliance of Hot Mix Asphalt
نویسنده(ها): ، ،
اطلاعات انتشار: هفتمین کنفرانس بین المللی پیشرفتهای علوم و تکنولوژی، سال
تعداد صفحات: ۸
In recent years, many researches were down to improve service life of asphalt pavement quality against vehicles dynamic loads. For this purpose, researchers investigated different ways such as changing the aggregate gradation and using of additive material to modify bitumen and asphalt mixture. One of this ways is using of additive materials to improvement of asphalt properties against dynamic loads. Due to unique characteristics of nano materials, using of them in asphalt mixtures has been interested. Therefore, in this study the effect of nano zinc oxide (ZnO) in improvement of mechanical properties of hot mix asphalt (HMA) has been investigated. To achieve this goal, mixtures with different content of bitumen and nano zinc oxide were made and the effect of these parameters was investigated on the modified mixture in compare with conventional asphalt mixture. The results showed that adding of nano zinc oxide to HMA had a great effect in the improvement of permanent deformation of HMA.<\div>

۶Effects of using carbon nano tubes on thermal and ductility properties of bitumen
نویسنده(ها): ، ، ،
اطلاعات انتشار: هفتمین کنگره ملی مهندسی عمران، سال
تعداد صفحات: ۶
New plans must be used to improve quality and to increase productivity and duribility of convetional pavements. In this investigation,it has been attempted to promote technical characteristics of bitumen using carbon nanotubes as an additive. Wet and dry process methods are most practical ways of mixing CNF in AC. It was decided that the best method to adopt for this investigation was the dry process.In this study thermal and ductility properties of modified bitumen by 0.1, 0.5, and 1% carbon nano tube content in bitumen were evaluated considering bitumen penetration, softening point, and ductility tests, then the results were compared to those of unmodified bitumen. It was found that adding carbon nano tubes effects on thermal properties of bitumen by increasing the softening point, and decreasing the bitumen penetration. It was also shown that bitumen ductility decreases by carbon nano tubes modification process.<\div>

۷Enhancing the compressive strength of clayey sand soils by using Iron Oxide Nanoparticles II
نویسنده(ها): ، ،
اطلاعات انتشار: دهمین کنگره بین المللی مهندسی عمران، سال
تعداد صفحات: ۷
Nano oxide ingredients often called ceramic oxide components include a wide range of nanoparticles. Some of these nano scale materials like silica nano–particles have been considered by experiments for enhancing the soil features. In this study, for the first time, we have investigated the usage of iron oxide nanoparticles II to improve the compressive strength of the soil. To do so, using the clayey sand soil and iron oxide nanoparticles II, by the manner of mixing via ball mill, laboratory samples have been afforded and subjected to the axial test. Results of this study showed that by using a mixture of 0.2%, 0.5%, 1%, 2%, 3% weight of iron oxide nanoparticles in the soil by the best procedure of mixing nano ingredients with ball mill, the compressive strength of these kinds of soils will be increased up to almost 50%<\div>

۸Estimating moisture sensitivity of asphalt mixtures with using Wetfix and ZycoTherm as anti–stripping additives
نویسنده(ها): ،
اطلاعات انتشار: دهمین کنگره بین المللی مهندسی عمران، سال
تعداد صفحات: ۱۲
There are several approaches for improving adhesion and moisture strength in asphalt mixtures, one of which is to adding liquid anti–stripping to base bitumen. Two types of aggregates, limestone and granite, and two types of anti–stripping additives, namely Wetfix N422 and ZycoTherm, as well as AC 60–70 as base bitumen were evaluated in this study by the help of surface free energy concept and modified lottman test. The results showed that adding anti–stripping causes the total surface free energy of the bitumen to increase, resulting in a decrease in stripping between the aggregate and bitumen in the presence of water. The results of modified lottman test showed that the ratio of wet\dry values of ITS for mixtures containing anti–stripping was higher than those of the samples with base bitumen. The bitumen treated with ZycoTherm also showed better resistance against moisture damage in both aggregates were used in this study<\div>

۹The effect of rice husk ash on the rutting performance of asphalt mixtures
نویسنده(ها): ،
اطلاعات انتشار: سومین کنفرانس بین المللی پژوهشهای کاربردی در مهندسی عمران، معماری و مدیریت شهری، سال
تعداد صفحات: ۷
Nowadays, saving energy and recycling materials are becoming priorities in the road construction Industry. This paper presents the experimental results on the utilization of rice hush ash (RHA) as a replacement for mineral filler in hot mix asphalt (HMA) mixture. Five different HMA mixtures were and to determine the optimal asphalt binder content. HMA mixtures containing RHA was changed with mineral filler in the rate of 25%, 50%, 75%, and 100%. The results ofa laboratory study for evaluating the properties of HMA mixtures were investigated usingMarshall stability and dynamic creep tests.As a result, it has come in view that RHA can be used as mineral filler in the asphalt mixture<\div>
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