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Stability of buckling-restrained steel plate shear walls with inclined-slots: Theoretical analysis and design recommendations Shuangshuang Jin a, Jinping Oua,b,⁎, J.Y. Richard Liewc,d a School of Civil Engineering, Harbin Institute of Technology, Harbin 150090, China b Key Lab of Structures Dynamic Behavior and Control (Harbin Institute of Technology), Ministry of Education, Harbin 150090, China c Department of Civil & Environmental Engineering, National University of Singapore, Singapore d College of Civil Engineering, Nanjing Tech University, China a b s t r a c t Article history: Received 19 April 2015 Received in revised form 27 September 2015 Accepted 2 October 2015 Available online xxxx Keywords: Energy dissipation device Steel plate shear wall (SPSW) Buckling-restrained Stability Numerical analysis Design This paper presents a novel buckling-restrained steel plate shear wall with inclined slots called slotted SPSW to be used as an energy dissipation device for earthquake resistance. In the slotted SPSW, a steel plate with inclined slotted holes is sandwiched in between two external concrete panels which provide lateral restraint to achieve stable energy dissipation under cyclic reversal loading. Theoretical analysis and finite element monotonic pushover analyses are conducted to investigate the stability of slotted SPSWs. Global buckling and local buckling resistances of slotted SPSWs are determined. Some key parameters, such as the gap between steel plate and concrete panels, bolt spacing, width of steel strips, and steel panel slenderness, are investigated through numerical analyses. The shear force and lateral drift behavior of the slotted SPSW is found to be affected by the physical gap between the concrete panels and inner steel plate. The minimumconcrete panel thickness for providing the effective lateral restraint to prevent buckling failure of the inner steel plate is determined based on the bolt spacing. 10.1016_J.JCSR.2015.10.002-Stability-of-buckling-restrained-steel-plate-shear-walls-with-inclined-slots-Theoretical-analysis-and-design-recommendations.pdf

OPTIMIZATION OF I-SECTION PROFILE DESIGN BY THE FINITE ELEMENT METHOD ABSTRACT: This paper discusses the problem of design optimization for an I-section profile. The optimization process was performed using the Abaqus program. The numerical analysis of a strictly static problem was based on the finite element method. The scope of the analysis involved both determination of stresses and displacements in the profile and structure topology optimization. The main focus of the numerical analysis was put on reducing profile volume while maintaining the same load and similar stresses prior to and after optimization. The solution of the optimization problem is just an example of the potential of using this method in combination with the finite element method in the Abaqus environment. Nowadays numerical analysis is the most effective cost-reducing alternative to experimental tests and it enables structure examination by means of a computer. منبع دانلود OPTIMIZATION OF I-SECTION.pdf

NUMERICAL ANALYSIS OF SEDIMENT TRANSPORT IN SEWER PIP H. Bonakdari, I. Ebtehaj and H. Azimi Abstract The efficiency and economical performance of sewer systems is an essential issue in urban drainage. The need for sewers to carry sediment has been recognized for many years. One of the main problems in designing sewerage systems is the sediment deposition. Sedimentation in sewers occurs regularly according to the alternating natural flow. The present study investigates the hydraulic characteristics of flow in channels with a circular cross section with different bed slope and their effects on sediment transport capacity by use of 3D numerical simulation of flow field with ANSYS-CFX software. It studies hydraulic features of the flow passing through a circular channel in a two or three phase conditions. Self-cleansing velocity and volumetric sediment concentration in various Froude numbers were compared by lab outcomes to validate the results of numerical model. Results of numerical simulation indicate a proper adaptation of numerical and experimental models. Longitudinal velocity counters obtained by numerical simulation are compared in two or three phase flows. Keywords Sediment transport; Non-deposition; Numerical Analysis; ANSYS-CFX چکیده عملکرد موثر و اقتصادی سیستم­های فاضلاب یکی از مسائل مهم در زهکشی شهری به حساب می­آید. استفاده از سیستم­های فاضلاب به منظور انتقال رسوب از سال ها پیش مورد توجه بوده است. یکی از مشکلات اساسی در طراحی این سیستم­ها، ته نشینی رسوب در بستر کانال است. رسوبگذاری با توجه به جریان متناوب طبیعی اتفاق می افتد. در این مطالعه مشخصات هیدرولیکی جریان در کانال دایره ای با شیب­های مختلف و اثر آن بر روی ظرفیت انتقال رسوب با استفاده از شبیه­سازی سه بعدی میدان جریان با استفاد ه از ANSYS-CFX بررسی می­شود. در این شبیه­سازی عددی از مدل آشفتگی k-ε استاندارد استفاده شده و مشخصات هیدرولیکی جریان عبوری از داخل یک کانال دایروی در شرایط دو و سه فازی مورد بررسی قرار گرفته است. به منظور اعتبار سنجی نتایج مدل عددی سرعت خودشویی و غلظت حجمی رسوب در عدد فرودهای مختلف با نتایج آزمایشگاهی مقایسه شده است. نتایج حاصل شبیه­سازی عددی نشان دهنده انطباق مناسب مدل عددی با مدل آزمایشگاهی است. در ادامه کانتورهای سرعت طولی شبیه­سازی شده در جریان­های دو و سه فازی با یکدیگر مقایسه شده است. همچنین پروفیل­های سرعت در دو حالت جریان دو و سه فازی و تغییرات تراز بستر کانال مورد مطالعه قرار گرفته است. منبع دانلود 28-11-3.pdf

The Stability Assessment of Dasht-e-Abbas Pressure Intake Tunnel Subjected to Ground Strength Reduction-Iran S. M Mir Mohammad Hosseini 1 ; P Malek Mohammadi2 ; M Kargar3 The hydraulic pressure is one of the most important factors in the design of pressure intake tunnels. Since the surrounding media cannot usually resist the high internal pressure of these tunnels, they are usually finished with an adequate lining mostly of reinforced concrete, which is an interaction problem between water, soil or rock and concrete lining. Although reinforcing the concrete lining may reduce the width and number of the developed cracks in the lining, the penetration of water into the surrounding media can still happen due to high water pressure in the tunnel. Thus, it may lead to the development of hydro pressure on the external surface of the lining. There are some theoretical methods that are developed for the design of tunnel lining in this condition. When the tunnel is located above the underground water table, the seeping water may lead to strength reduction of the adjacent soils, particularly when the ground, like the mudstone layers existing in Dasht-e-Abbas region, south-west of Iran, is cohesive and consists of soils that are susceptible to water. In this paper, the hydrostatic interaction between soil and concrete lining of Dasht-e-Abbas pressure intake tunnel has been investigated when the shear strength parameters of the mudstone layers decrease due to the seepage of water to the surrounding media. To evaluate the stability of the tunnel, a two dimensional numerical simulation is developed using the finite element code called PLAXIS and interaction analyses are carried out. The analyses are done in stages to assess the maximum internal forces induced in the lining. The structural stability of the tunnel is evaluated and discussed in this condition. Based on the obtained results, it is noted that for more realistic understanding of the behavior of infrastructures like pressure intake tunnels under various conditions, numerical analyses should also accompany experimental and analytical approaches such as Schleiss method which is described in this paper, especially for tunneling in media that is susceptible to water and ground strength reduction. The numerical analysis results show a considerable increase in the lining internal forces when subjected to the reduction of ground strength. However, the tunnel structure is still stable under the effect of surrounding ground degradation with the constructed lining specifications. منبع دانلود JSEG101329597000.pdf