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مجله STRUCTURE ، ژانویه 2018 فایل پی دی اف در 60 صفحه برخی از مطالب این نشریه : Post-Tensioned Concrete Construction Tendon Repairs and Modifications Fire Resistance of Flat Plate Voided Concrete Floor Systems Key Differences and Practical Applications for Cement and Gypsum Underlayments Support Restraints and Strength of Post-Tensioned Members Wood-Framed Shear Walls : Utilizing Force Transfer Around Openings Shrinkage-Compensating Concrete Designs Post-Installed Adhesive Anchor Systems : Reinforcing Bar Development Length using the Provisions of ACI 318 Structural Engineers and Climate Change 2018 IBC and 2018 IEBC Changes Related to Wood Construction Connecting Chicago’s “Second Shoreline” منبع دانلود از پیوست structure magazine 01 jan 2018.pdf

CLIMATE CHANGE IMPACT ON PRECIPITATION EXTREME EVENTS IN UNCERTAINTY SITUATION; PASSING FROM GLOBAL SCALE TO REGIONAL SCALE M. J. Khordadi, A. Alizadeh, M. Nassiri Mahallati, H. Ansari and H. Sanaeinejad Abstract Global warming and then climate change are important topics studied by researchers throughout the world in the recent decades. In these studies, climatic parameters changes are investigated. Considering large-scaled output of AOGCMs and low precision in computational cells, uncertainty analysis is one of the principles in doing hydrological studies. For this reason, it is tried that investigating the uncertainty due to precision of computational cells and in passing from global scale to regional scale through LARS-WG model and CRU institute, precipitation changes in Mashhad synoptic station located in Ghareghom basin are studied. The results show enough ability of the model to simulate precipitation parameter in the base period. Using downscaled output of HadCM3 generated by CRU with high precision shows gradual decreasing of precipitation trend for frequency and sum values. Comparing the downscaled output of the AOGCM with 2.5*3.75 resolution and the output of CRU with 0.5*0.5 resolution, the uncertainty is due to precision of computational cells from global to regional scale which the latter scale is closer to real values. Keywords climate change, CRU, downscaling, LARS-WG, uncertainty چکیده گرمايش جهاني و به تبع آن تغيير اقليم موضوع مهمي است که در دهه­هاي اخير توسط محققين در سرتاسر دنيا مورد مطالعه قرار گرفته است. در اين مطالعات تغييرات پارامترهاي اقليمي مورد بررسي قرار مي­گيرد. با توجه به بزرگ مقياس بودن داده­هاي مربوط به AOGCM و کم دقت بودن سلول محاسباتي آن­ها، تحليل عدم قطعيت يکي از موارد اصولي و زيربنايي جهت انجام کليه مطالعات هيدرولوژيکي مي­باشد. بدين منظور در اين مطالعه تلاش شد با بررسي عدم قطعيت ناشي از دقت سلول محاسباتي در حالت گذار از مقياس جهاني به منطقه­اي توسط مدل LARS-WG و مرکز CRU تغييرات پارامتر بارندگي در ايستگاه سينوپتيک مشهد واقع در حوضه قره قوم مطالعه شود. نتايج حاصل نشان دهنده توانايي تقريبا بالاي مدل در شبيه­سازي پارامتر بارندگي در دوره پايه تلقي گرديد. استفاده از خروجي ريز مقياس شده مدل HadCM3 که توسط مرکز CRU با دقت مکاني بالا توليد گرديده بود، کاهش تدريجي روند بارندگي براي مقادير فراواني و مجموع سه شاخص تعريف شده را نشان داد. با مقايسه خروجي ريزمقياس شده مدل مذکور با دقت 3.75×2.5 و خروجي مرکز CRU با دقت 0.5×0.5 عدم قطعيت ايجاد شده مربوط و ناشي از دقت سلول محاسباتي از مقياس جهاني به منطقه­اي ارزيابي مي­گردد که به واقعيت نزديک­تر خواهد بود. منبع دانلود 28-8-5.pdf

Dynamic characteristics of monthly rainfall in Tabriz under climate change Original Article, C37 Jani R, Ghorbani M.A, Saghafian B, Shamsaei A, zahabion B. Journal. Civil Eng. Urban. 3(4):225-235. 2013 ABSTRACT:Among the factors creating the changes in climate include ever-increasing population, changes in land usage and the development of industrial activities. Thus, studying the effect of this phenomenon on hydrological processes, in particular rainfall is considered as one of the most important issues concerning water engineering. Chaos theory is a tool that can be implemented besides other methods in modeling nonlinear, complicated hydrological phenomena like rainfall, due to its wonderful capabilities. In this study, monthly rainfall in Tabriz has been studied through this theory under historical and climate change conditions. In so doing, the statistical period of 1971 to the year 2000 was considered as the historical period, and the results obtained from the model LARS-WG were also considered under two scenarios in three future periods. The results indicated that historical period data having the fractal dimension of (5.96) has good chaotic nature. In the case of scenario A2, the data of all three series had good chaotic nature as well. In scenario B1, random investigation in all three periods will be appropriate. Keywords: Climate Change, Rainfall, Chaotic Theory, Tabriz, Lars-WG Model. منبع: [Hidden Content] دانلود: [Hidden Content].,37-225-233.pdf J. Civil Eng. Urban.,37-225-233.pdf