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Topology optimization and seismic collapse assessment of shape memory alloy (SMA)-braced frames: Effectivenessof Fe-based SMAs

Aydin HASSANZADEH; Saber MORADI

《结构与土木工程前沿(英文)》 2022年 第16卷 第3期   页码 281-301 doi: 10.1007/s11709-022-0807-3

摘要: This paper presents a seismic topology optimization study of steel braced frames with shape memory alloy (SMA) braces. Optimal SMA-braced frames (SMA-BFs) with either Fe-based SMA or NiTi braces are determined in a performance-based seismic design context. The topology optimization is performed on 5- and 10-story SMA-BFs considering the placement, length, and cross-sectional area of SMA bracing members. Geometric, strength, and performance-based design constraints are considered in the optimization. The seismic response and collapse safety of topologically optimal SMA-BFs are assessed according to the FEMA P695 methodology. A comparative study on the optimal SMA-BFs is also presented in terms of total relative cost, collapse capacity, and peak and residual story drift. The results demonstrate that Fe-based SMA-BFs exhibit higher collapse capacity and more uniform distribution of lateral displacement over the frame height while being more cost-effective than NiTi braced frames. In addition to a lower unit price compared to NiTi, Fe-based SMAs reduce SMA material usage. In frames with Fe-based SMA braces, the SMA usage is reduced by up to 80%. The results highlight the need for using SMAs with larger recoverable strains.

关键词: topology optimization     shape memory alloy     Fe-based SMA     steel braced frames     performance-based seismic design     collapse assessment    

Cadmium removal mechanistic comparison of three Fe-based nanomaterials: Water-chemistry and roles ofFe dissolution

《环境科学与工程前沿(英文)》 2022年 第16卷 第12期 doi: 10.1007/s11783-022-1586-8

摘要:

● nZVI, S-nZVI, and nFeS were systematically compared for Cd(II) removal.

关键词: Nano zero valent iron     Sulfided zero valent iron     FeS     Cd(II) immobilization     Fe dissolution    

Controllable Fe/HCS catalysts in the Fischer-Tropsch synthesis: Effects of crystallization time

Yifei Wang, Shouying Huang, Xinsheng Teng, Hongyu Wang, Jian Wang, Qiao Zhao, Yue Wang, Xinbin Ma

《化学科学与工程前沿(英文)》 2020年 第14卷 第5期   页码 802-812 doi: 10.1007/s11705-019-1866-4

摘要: The Fischer–Tropsch synthesis (FTS) continues to be an attractive alternative for producing a broad range of fuels and chemicals through the conversion of syngas (H and CO), which can be derived from various sources, such as coal, natural gas, and biomass. Among iron carbides, Fe C, as an active phase, has barely been studied due to its thermodynamic instability. Here, we fabricated a series of Fe C embedded in hollow carbon sphere (HCS) catalysts. By varying the crystallization time, the shell thickness of the HCS was manipulated, which significantly influenced the catalytic performance in the FTS. To investigate the relationship between the geometric structure of the HCS and the physic-chemical properties of Fe species, transmission electron microscopy, X-ray diffraction, N physical adsorption, X-ray photoelectron spectroscopy, hydrogen temperature-programmed reduction, Raman spectroscopy, and Mössbauer spectroscopy techniques were employed to characterize the catalysts before and after the reaction. Evidently, a suitable thickness of the carbon layer was beneficial for enhancing the catalytic activity in the FTS due to its high porosity, appropriate electronic environment, and relatively high Fe C content.

关键词: Fischer–Tropsch synthesis     Fe-based catalyst     Fe2C     hollow carbon sphere     crystallization time    

Parametric study on damage control design of SMA dampers in frame-typed steel piers

Xiaoqun LUO, Hanbin GE, Tsutomu USAMI,

《结构与土木工程前沿(英文)》 2009年 第3卷 第4期   页码 384-394 doi: 10.1007/s11709-009-0065-7

摘要: This paper focuses on damage control design of SMA dampers in steel frame piers. A parametric study based on time history analyses is carried out on frame-typed bridge piers with axial-type SMA damping device. The parameters examined are design parameters of strength ratio and stiffness ratio . Seismic performance indexes on displacement and strain are investigated under three JRA recommended Level 2 Ground Type П strong earthquake motions. Design recommendations are suggested following the results of the parametric study.

关键词: damage control design     shape memory alloy     parameter study     displacement-based verification     strain-based verification     time history analysis    

Seismic responses and resilience of novel SMA-based self-centring eccentrically braced frames under near-fault

Zhi-Peng CHEN; Songye ZHU

《结构与土木工程前沿(英文)》 2022年 第16卷 第8期   页码 962-975 doi: 10.1007/s11709-022-0873-6

摘要: In this paper, the seismic responses and resilience of a novel K-type superelastic shape memory alloy (SMA) self-centring (SC) eccentrically braced frame (EBF) are investigated. The simulation models of the SMA-based SC-EBF and a corresponding equal-stiffness traditional EBF counterpart are first established based on some existing tests. Then twenty-four near-fault ground motions are used to examine the seismic responses of both EBFs under design basis earthquake (DBE) and maximum considered earthquake (MCE) levels. Structural fragility and loss analyses are subsequently conducted through incremental dynamic analyses (IDA), and the resilience of the two EBFs are eventually estimated. The resilience assessment basically follows the framework proposed by Federal Emergency and Management Agency (FEMA) with the additional consideration of the maximum residual inter-storey drift ratio (MRIDR). The novel SMA-based SC-EBF shows a much better resilience in the study and represents a promising attractive alternative for future applications.

关键词: shape memory alloy     eccentrically braced frame     self-centring     fragility     loss function     resilience    

Experimental flexural behavior of SMA-FRP reinforced concrete beam

Adeel ZAFAR, Bassem ANDRAWES

《结构与土木工程前沿(英文)》 2013年 第7卷 第4期   页码 341-355 doi: 10.1007/s11709-013-0221-y

摘要: The most critical drawback in currently used steel reinforcement in reinforced concrete (RC) structures is susceptibility to accumulation of plastic deformation under excessive loads. Many concrete structures due to damaged (yielded) steel reinforcement have undergone costly repairs and replacements. This research presents a new type of shape memory alloy (SMA)-based composite reinforcement with ability to withstand high elongation while exhibiting pseudo-elastic behavior. In this study, small diameter SMA wires are embedded in thermoset resin matrix with or without additional glass fibers to develop composite reinforcement. Manufacturing technique of new proposed composite is validated using microscopy images. The proposed SMA-FRP composite square rebars are first fabricated and then embedded in small scale concrete T-beam. 3-point bending test is conducted on manufactured RC beam using a cyclic displacement controlled regime until failure. It is found that the SMA-FRP composite reinforcement is able to enhance the performance of concrete member by providing re-centering and crack closing capability.

关键词: re-centering     shape memory alloys     concrete     composite     fiber reinforced polymer     scanning electron microscopy    

Lignin-based electrospun nanofiber membrane decorated with photo-Fenton Ag@MIF-100(Fe) heterojunctions

《化学科学与工程前沿(英文)》 2023年 第17卷 第7期   页码 930-941 doi: 10.1007/s11705-023-2309-9

摘要: Membrane technology for wastewater remediation has aroused wide interest owing to its unique properties and potential applications. However, it remains challenging to explore green, efficient and robust membrane material and technique for complex wastewater treatment. Herein, we proposed using a simple electrospinning and in situ seeding method to fabricate a lignin-based electrospun nanofiber membrane (LENM) decorated with photo-Fenton Ag@MIL-100(Fe) heterojunctions for efficient separation of oil/water emulsions and degradation of organic dye. Thanks to the embedded lignin in LENM, an ultrahigh MIL-100(Fe) loading (53 wt %) with good wettability and high porosity was obtained. As a result, the hybrid Ag@MIL-100(Fe)/LENM exhibited excellent oil/water emulsions separation efficiency (more than 97%) without a compromise of water flux. Moreover, the hybrid membrane showed an excellent dye removal with degradation of 99% methylene blue within 30 min under illumination, which is attributed to a synergy of dye adsorption/enrichment and photo-Fenton catalytic degradation from Ag@MIL-100(Fe). Therefore, the lignin-based photo-Fenton hybrid membrane can lay the foundation for the preparation and application of green, sustainable and versatile membrane materials and technologies for efficient complex wastewater remediation.

关键词: lignin     electrospinning     heterojunctions     photo-Fenton catalysis     wastewater remediation    

Grafting of PEG400 onto the surface of LLDPE/SMA film

CHEN Gufeng, ZHANG Yi, XU Jiarui, ZHU Yafei

《化学科学与工程前沿(英文)》 2007年 第1卷 第2期   页码 128-131 doi: 10.1007/s11705-007-0024-6

摘要: Linear low-density polyethylene (LLDPE) was melt and blended with styrene-maleic anhydride copolymer (SMA). The blending films were then immersed in poly(ethylene glycol)400 (PEG400) at room temperature. The surface composition of the blend films was determined by Fourier transform infra-red spectroscopy coupled with a variable incidence angle attenuated total reflection accessory (ATR-FTIR). Results show that PEG400 can be grafted onto the surface of the films via esterification with SMA. The immersion of PEG promotes the enrichment of SMA onto the surface of the films. The water contact angle data show that grafting of PEG400 onto PE can greatly improve the hydrophilicity of the PE surface. These experiments show that surface functionalization of polyethylene films by blending SMA and then surface grafting of PEG is feasible, which suggest an effective and simple route for PE surface modification via blending and grafting.

关键词: hydrophilicity     temperature     effective     immersion     reflection accessory    

Corrosion behavior of Fe–Cr–Ni based alloys exposed to molten MgCl2–KCl–NaCl salt with over-added

《化学科学与工程前沿(英文)》 2023年 第17卷 第10期   页码 1608-1619 doi: 10.1007/s11705-023-2349-1

摘要: MgCl2–NaCl–KCl salts mixture shows great potential as a high-temperature (> 700 °C) thermal energy storage material in next-generation concentrated solar power plants. Adding Mg into molten MgCl2–NaCl–KCl salt as a corrosion inhibitor is one of the most effective and cost-effective methods to mitigate the molten salt corrosion of commercial Fe–Cr–Ni alloys. However, it is found in this work that both stainless steel 310 and Incoloy 800H samples were severely corroded after 500 h immersion test at 700 °C when the alloy samples directly contacted with the over-added Mg in the liquid form. The corrosion attack is different from the classical impurity-driven corrosion in molten chloride salts found in previous work. Microscopic analysis indicates that Ni preferentially leaches out of alloy matrix due to the tendency to form MgNi2/Mg2Ni compounds. The Ni-depletion leads to the formation of a porous corrosion layer on both alloys, with the thickness around 204 µm (stainless steel 310) and 1300 µm (Incoloy 800H), respectively. These results suggest that direct contact of liquid Mg with Ni-containing alloys should be avoided during using Mg as a corrosion inhibitor for MgCl2–NaCl–KCl or other chlorides for high temperature heat storage and transfer.

关键词: concentrated solar power (CSP)     Mg corrosion inhibitor     Mg–Ni intermetallic     salt purification     thermal energy storage (TES)    

A modular design kit for task-adaptable low-cost robots based on BaPaMan design

G. BORCHERT, C. L?CHTE, G. CARBONE, A. RAATZ

《机械工程前沿(英文)》 2013年 第8卷 第1期   页码 33-41 doi: 10.1007/s11465-013-0356-5

摘要:

This paper discusses the redesign of a binary parallel manipulator named BaPaMan (Binary Actuated Parallel Manipulator). The aim of this work is the improvement of the structures stiffness of BaPaMan. Additionally this paper shows the implementation of a construction kit which allows task-adaptation of low-cost robots based on the BaPaMan structure. BaPaMan is a three degree of freedom (DOF) spatial parallel robot which comprises flexure hinges and Shape Memory Alloy (SMA) actuators to achieve a low-cost design, well suited for easy operation applications. Measurements have shown that this comes at the cost of poor structural stiffness and end effector accuracy. To counter these issues BaPaMan2 and BaPaMan3 have been developed and are elaborated within this work. During the design phase, an empirical FEA is used to improve the flexure hinge performance, which analyses relations between several design parameters and the stiffness of the entire system. Finally, task-adaptation is achieved by using a design methodology and a parametric CAD model for BaPaMan. Besides the paper introduces first applications of the BaPaMan structure and shows future work.

关键词: binary actuation     flexure hinges     SMA actuators     low-cost     design kit     task-adaptation    

The performance of nitrate-reducing Fe(II) oxidation processes under variable initial Fe/N ratios: The

《环境科学与工程前沿(英文)》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1366-2

摘要:

•Bacterially-mediated coupled N and Fe processes examined in incubation experiments.

关键词: Denitrification     N2O emission     Fe(II) oxidation     Fe/N ratio     Fe minerals    

Enhanced reductive degradation of carbon tetrachloride by carbon dioxide radical anion-based sodium percarbonate/ Fe(II)/formic acid system in aqueous solution

Wenchao Jiang, Ping Tang, Shuguang Lu, Xiang Zhang, Zhaofu Qiu, Qian Sui

《环境科学与工程前沿(英文)》 2018年 第12卷 第2期 doi: 10.1007/s11783-017-0987-6

摘要: The performance of sodium percarbonate (SPC) activated with ferrous ion (Fe(II)) with the addition of formic acid (FA) to stimulate the degradation of carbon tetrachloride (CT) was investigated. Results showed that CT could be entirely reduced within 15 min in the system at a variety of SPC/Fe(II)/FA/CT molar ratios in experimental level. Scavenging tests indicated that carbon dioxide radical anion (CO2· ) was the dominant reactive oxygen species responsible for CT degradation. CT degradation rate, to a large extent, increased with increasing dosages of chemical agents and the optimal molar ratio of SPC/Fe(II)/FA/CT was set as 60/60/60/1. The initial concentration of CT can hardly affect the CT removal, while CT degradation was favorable in the pH range of 3.0–9.0, but apparently inhibited at pH 12. Cl and HCO of high concentration showed negative impact on CT removal. Cl released from CT was detected and the results confirmed nearly complete mineralization of CT. CT degradation was proposed by reductive C-Cl bond splitting. This study demonstrated that SPC activated with Fe(II) with the addition of FA may be promising technique for CT remediation in contaminated groundwater.

关键词: Carbon tetrachloride     Sodium percarbonate     Formic acid     Reductive radicals     Groundwater    

Implementation of an optimum algorithm for structural reliability analysis based on FEM

CHENG Ying, TU Hong-mao, FAN Hong-li

《机械工程前沿(英文)》 2006年 第1卷 第4期   页码 468-471 doi: 10.1007/s11465-006-0061-8

摘要: To analyze structural reliability by the stochastic FE (finite element) method rapidly and efficiently, a method combined with the FE method and gradient optimum algorithm based on ANSYS was presented when referring to the geometric interpretation of structural reliability index. ANSYS-based development was adopted to implement it. Results of an example demonstrate that the method requires fewer FE calculations compared with the design point method and Monte-Carlo simulation, and achieves satisfactory accuracy.

关键词: satisfactory     interpretation     algorithm     structural reliability     stochastic FE    

福岛核事故后中国广东核电集团核电厂抗震设计和评估进展

毛庆,吴应喜,张健,孟阿军,张涛,杨春菊,刘芳

《中国工程科学》 2013年 第15卷 第4期   页码 46-51

摘要:

本文介绍了核电站抗震设计要求、在建和运行核电站的抗震设计情况以及运行核电站遭遇地震灾害的情况,简述了福岛核事故后世界各国核电站在抗震方面采取的措施,针对中国广东核电集团在福岛核事故后的行动进行了详细介绍,并提出了新建核电厂在抗震设计和评估方面的策略,以期通过技术手段持续提升核电站的抗震能力。

关键词: 抗震设计基准     超设计基准地震     抗震裕量分析(SMA    隔震    

A magnetic adsorbent based on salicylic acid-immobilized magnetite nano-particles for pre-concentration

Hossein Abdolmohammad-Zadeh, Arezu Salimi

《化学科学与工程前沿(英文)》 2021年 第15卷 第2期   页码 450-459 doi: 10.1007/s11705-020-1930-0

摘要: In this research, an eco-friendly magnetic adsorbent based on Fe O /salicylic acid nanocomposite was fabricated using a facile one-pot co-precipitation method. The crystalline and morphological characterization of the prepared nanocomposite was performed by field emission scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. The nanocomposite was employed as a magnetic solid-phase extraction agent for separation of Cd(II) ions from synthetic solutions. Some experimental factors affecting the extraction efficiency were investigated and optimized. Following elution with acetic acid (pH 3.5), the pre-concentrated analyte was quantified by flame atomic absorption spectrometry. In optimal conditions, a linear calibration graph was achieved in the concentration range of 0.2‒30 ng·mL with a determination coefficient ( ) of 0.9953. The detection limit, the enhancement factor, inter- and intra-day relative standard deviations (for six consecutive extractions at the concentration level of 10 ng·mL ) were 0.04 ng·mL , 100, 2.38% and 1.52%, respectively. To evaluate the accuracy of the method, a certified reference material (NIST SRM 1643e) was analyzed, and there was a good agreement between the certified and the measured values. It was successfully utilized to determine cadmium in industrial wastewater samples and the attained relative recovery values were between 96.8% and 103.2%.

关键词: cadmium     magnetic solid-phase extraction     Fe3O4 nanoparticles     Fe3O4/salicylic acid nanocomposite     flame atomic absorption spectrometry    

标题 作者 时间 类型 操作

Topology optimization and seismic collapse assessment of shape memory alloy (SMA)-braced frames: Effectivenessof Fe-based SMAs

Aydin HASSANZADEH; Saber MORADI

期刊论文

Cadmium removal mechanistic comparison of three Fe-based nanomaterials: Water-chemistry and roles ofFe dissolution

期刊论文

Controllable Fe/HCS catalysts in the Fischer-Tropsch synthesis: Effects of crystallization time

Yifei Wang, Shouying Huang, Xinsheng Teng, Hongyu Wang, Jian Wang, Qiao Zhao, Yue Wang, Xinbin Ma

期刊论文

Parametric study on damage control design of SMA dampers in frame-typed steel piers

Xiaoqun LUO, Hanbin GE, Tsutomu USAMI,

期刊论文

Seismic responses and resilience of novel SMA-based self-centring eccentrically braced frames under near-fault

Zhi-Peng CHEN; Songye ZHU

期刊论文

Experimental flexural behavior of SMA-FRP reinforced concrete beam

Adeel ZAFAR, Bassem ANDRAWES

期刊论文

Lignin-based electrospun nanofiber membrane decorated with photo-Fenton Ag@MIF-100(Fe) heterojunctions

期刊论文

Grafting of PEG400 onto the surface of LLDPE/SMA film

CHEN Gufeng, ZHANG Yi, XU Jiarui, ZHU Yafei

期刊论文

Corrosion behavior of Fe–Cr–Ni based alloys exposed to molten MgCl2–KCl–NaCl salt with over-added

期刊论文

A modular design kit for task-adaptable low-cost robots based on BaPaMan design

G. BORCHERT, C. L?CHTE, G. CARBONE, A. RAATZ

期刊论文

The performance of nitrate-reducing Fe(II) oxidation processes under variable initial Fe/N ratios: The

期刊论文

Enhanced reductive degradation of carbon tetrachloride by carbon dioxide radical anion-based sodium percarbonate/ Fe(II)/formic acid system in aqueous solution

Wenchao Jiang, Ping Tang, Shuguang Lu, Xiang Zhang, Zhaofu Qiu, Qian Sui

期刊论文

Implementation of an optimum algorithm for structural reliability analysis based on FEM

CHENG Ying, TU Hong-mao, FAN Hong-li

期刊论文

福岛核事故后中国广东核电集团核电厂抗震设计和评估进展

毛庆,吴应喜,张健,孟阿军,张涛,杨春菊,刘芳

期刊论文

A magnetic adsorbent based on salicylic acid-immobilized magnetite nano-particles for pre-concentration

Hossein Abdolmohammad-Zadeh, Arezu Salimi

期刊论文