نتایج جستجو برای: concrete placing

تعداد نتایج: 93964  

2007
Henrik Axelsson David Darwin Carl E. Locke

The mechanism of corrosion of reinforcing steel in concrete is discussed based on electrochemical and electron microscopy observations. The importance of calcium hydroxide precipitation on the steel surf ace in the steel/mortar interface is evaluated by placing filter paper around reinforcing steel bar specimens prior to casting in mortar, thus preventing direct contact between steel and mortar...

Journal: :iranian journal of radiation research 0
s.m.r. aghamiri radiation medicine department, shahid beheshti university, tehran, iran s.m.j. mortazavi medical physics department, school of medicine, shiraz university of medical sciences, shiraz, iran m.a. mosleh shirazi physics unit, radiotherapy department, shiraz university of medical sciences, shiraz, iran m. baradaran-ghahfarokhi medical physics and medical engineering department, school of medicine, isfahan university of medical sciences, isfahan, iran f. rahmani department of physics, knt university of technology, tehran, iran a. amiri chemical engineering department, new mexico state university, las cruces, new mexico, usa

background: high density concrete is extensively used for efficient radiation attenuation in radiotherapy rooms and nuclear reactors. over the past eight years, some efficient galena-based concrete samples for shielding x or gamma rays was produced. the goal of this study was to produce a novel high density concrete against neutron and photon radiations using tourmaline and galena. materials an...

پایان نامه :دانشگاه آزاد اسلامی واحد گرمی - دانشکده عمران 1393

کنترل کیفی در پروژه های عمرانی از اهمیت زیادی برخوردار است با این حال علیرغم میل باطنی مهندسین، کنترل کیفی بتن تازه و سخت شده به درستی انجام نمی شود. عدم وجود اطلاعات کافی نزد آزمایشگران و مهندسین موجب می گردد تا در مجموع نتوان کنترل کیفی مناسبی را به اجرا درآورد و یا پس از کسب نتایج مورد نظر نمی توان ارزیابی مناسبی را داشت. موضوع این پایان نامه، کنترل کیفی بتن رویه سد مخزنی شهر بیجار می باشد. ...

Journal: :journal of the structural engineering and geotechnics 0
n shamskia assistant professor, department of civil engineering, islamic azad university, qazvin branch, qazvin, iran

there is a worldwide interest in using fibers of different types in concrete mixtures. in this regard, as the use of pet fibers has gradually increased during the last decade, this study aims to investigate the effects of pet fibers on the mechanical properties of hardened concrete and the workability of fresh concrete. to this end, different contents of pet fibers (pc= %0, %0.5, %1 and %1.5) a...

Journal: :مهندسی عمران فردوسی 0
امیررضا پیلوار علی اکبر رمضانیان پور مهدی مهدی خانی فرامرز مودی

one of the main factors of premature deterioration of concrete structures is the corrosion of reinforcements. chloride penetration of concrete is one of the main reasons of this phenomenon. therefore, to have durable structure, it is necessary to have concretes with low permeability.there are various methods to evaluate permeability of concrete. finding a relationship between them can be useful...

Journal: :ACS Chemical Neuroscience 2016

Journal: :Brazilian Journal of Information Science 1969

Journal: :Archaeology International 2003

Journal: :Canadian Medical Association Journal 2013

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید