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Frontiers of Structural and civil engineering 2023年第1期17卷 122-137页

作者： Junqi HUANG Qing JIANG Xun CHONG Xianguo YE Caihua LIU School of civil and Hydraulic engineering Hefei University of TechnologyHefei 230009China Anhui Civil Engineering Structures and Materials Laboratory Hefei 230009China

In this study,a novel diagonally inserted bar-type basalt fiber reinforced polymer(BFRP)connector was proposed,aiming to achieve both construction convenience and partially composite behavior in precast concrete sandwich panels(PCSPs).First,pull-out tests were conducted to evaluate the anchoring performance of the connector in concrete after exposure to different temperatures.Thereafter,direct shear tests were conducted to investigate the shear performance of the connector.After the test on the individual performance of the connector,five façade PCSP specimens with the bar-type BFRP connector were fabricated,and the out-of-plane flexural performance was tested under a uniformly distributed load.The investigating parameters included the panel length,opening condition,and boundary condition.The results obtained in this study primarily indicated that 1)the bar-type BFRP connector can achieve a reliable anchorage system in concrete;2)the bar-type BFRP connector can offer sufficient stiffness and capacity to achieve a partially composite PCSP;3)the boundary condition of the panel considerably influenced the out-of-plane flexural performance and composite action of the investigated façade PCSP.

关键词： precast concrete sandwich panel basalt fiber reinforced polymer pull-out performance shear performance out-of-plane flexural performance

Influence of Associated Cations on the Transport and Adsorption of Chloride Ions in the Nano-channel of Calcium Aluminosilicate Hydrate Gel:A Molecular Dynamics Study

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Journal of Wuhan University of Technology(materials Science) 2022年第5期37卷 963-976页

作者：杨军 ZHANG Gaozhan 丁庆军 WANG Aiguo HOU Dongshuai anhui Province engineering laboratory of Advanced Building materials School of Materials and Chemical EngineeringAnhui Jianzhu UniversityHefei230601China State Key laboratory of Silicate materials for Architectures School of Materials Science and EngineeringWuhan University of TechnologyWuhan430070China School of materials Science and engineering Department of Civil EngineeringQingdao University of TechnologyQingdao266033China

Molecular dynamics simulation was utilized to investigate the transport and adsorption of chloride in the nanopore of calcium aluminosilicate hydrate(C-A-S-H)with associated cation types of Ca,Mg,Na and K.The local ionic structure,atomic dynamics and bond stability were analyzed to elucidate the interaction between cations and chloride ions.The results show that interfacial chloride is absorbed through the ion pairing formation in the vicinity of C-A-S-H substrate.Interfacial cations can simultaneously interact aluminosilicate chains,water molecules and Cl^(-)ions,which restrict the motion of interfacial Cl^(-)ions.Pore solution chloride can be immobilized through the solvation effect of cations.Cations along with their hydration shell can connect to neighboring Cl^(-)ions to decrease their mobility.Owing to the varied ionic chemistry,cations show different interaction strength with neighboring water molecules and anions,which determines the chloride transport behavior in the nanopore of C-A-S-H.The chloride immobilization capacity of C-A-S-H nanopore with different associated cations is listed in following order:Mg^(2+)Ca^(2+)

关键词： calcium aluminosilicate hydrate nanometer channel confinement chloride immobilization associated cations ionic structure

Dynamic soil-tunnel interaction in layered half-space for incident P-and SV-waves

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Earthquake Science 2015年第4期28卷 275-284页

作者： Jia Fu Jianwen Liang Lin Qin Department of civil engineering Tianjin University Tianjin Key laboratory of civil engineering structures & New materials

The dynamic soil-tunnel interaction is studied by the model of a rigid tunnel embedded in layered half-space, which is simplified as a single soil layer on elastic bedrock to the excitation of P- and SV-waves. The indirect boundary element method is used, combined with the Green＇ s function of distributed loads acting on inclined lines. It is shown that the dynamic characteristics of soil-tunnel interaction in layered half-space are different much from that in homoge- neous half-space, and that the mechanism of soil-tunnel interaction is also different much from that of soil-founda- tion-superstructure interaction. For oblique incidence, the tunnel response for in-plane incident SV-waves is com- pletely different from that for incident SH-waves, while the tunnel response for vertically incident SV-wave is very similar to that of vertically incident SH-wave.

关键词： Underground tunnel Layered half-space P-wave and SV-wave Indirect boundary element method Soil-tunnel interaction ~ Site dynamic characteristics

Fabrication of 3D hollow acorn-shell-like PtBi intermetallics via a surfactant-free pathway for efficient ethylene glycol electrooxidation

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Nano Research 2023年第5期16卷 6560-6567页

作者： Tingting Wan Xin Huang Sichen Li Qiuyu Li Xianlong Yang Zhenjie Sun Dong Xiang Kun Wang Peng Li Manzhou Zhu Department of Chemistry and Center for Atomic engineering of Advanced materials School of Materials Science and EngineeringAnhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized MaterialsAnhui UniversityHefei 230601China Key laboratory of Structure and Functional Regulation of Hybrid materials Ministry of EducationAnhui UniversityHefei 230601China

The synthesis of atomically ordered Pt-based intermetallic electrocatalysts for the direct alcohol fuel cells generally requires the addition of surfactants or the high-temperature annealing.However,some residual surfactants on the surface of the assynthesized catalysts would prevent the exposure of catalytic active sites,the high-temperature annealing process is easy to accelerate the sintering of the metal,which both lead to the decline of electrocatalytic performance.Herein,we construct the atomically ordered bimetallic PtBi intermetallics with clean surfaces and unique three-dimensional hollow acorn-shell-like structure(3D PtBi HASL)by a simple,low-temperature,surfactant-free one-pot synthetic approach.Benefiting from the special hollow structures,the obtained 3D PtBi HASL intermetallics expose abundant accessible active sites.Moreover,the introduction of oxophilic metal Bi can enhance adsorption of OHads,thereby significantly facilitating removal of poisoned intermediates.Density functional theory(DFT)simulations further indicate that formation of the PtBi intermetallic phase with the downshift of the Pt d-band center endows 3D Pt49.4Bi50.6 HASL intermetallics with significantly attenuated COads and enhanced OHads adsorption,bringing about the boosting electrocatalytic property.The mass activity of the 3D Pt49.4Bi50.6 HASL intermetallics for ethylene glycol oxidation reaction is as high as 24.67 A·mgPt^(−1),which is 12.98 times higher than that of commercial Pt/C(1.90 A·mgPt^(−1)).This work may inspire the design of Pt-based intermetallics as high-efficiency anode electrocatalysts for fuel cell applications.

关键词： surfactant-free strategy PtBi intermetallic three-dimensional hollow structure electrocatalyst ethylene glycol oxidation reaction

将磁斯格明子和反斯格明子通过磁布洛赫点四极子相连

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Science Bulletin 2023年第23期68卷 2919-2923,M0004页

作者：汤进吴耀东蒋佳良孔令尧刘威王守国田明亮杜海峰 School of Physics and Optoelectronic engineering Anhui UniversityHefei 230601China anhui Province Key laboratory of Condensed Matter Physics at Extreme Conditions High Magnetic Field LaboratoryHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Information materials and Intelligent Sensing laboratory of anhui Province Institutes of Physical Science and Information TechnologyAnhui UniversityHefei 230601China anhui Key laboratory of Magnetic Functional materials and Devices School of Materials Science and EngineeringAnhui UniversityHefei 230601China

类似于粒子-反粒子,斯格明子与反斯格明子具有相反的拓扑序参量.斯格明子-反斯格明子耦合态具有特殊的拓扑磁电特性,例如霍尔天平动力学,可以用来开发赛道存储等新型拓扑自旋电子学器件.本文结合理论计算与实空间观测手段,在一类焦点材... 详细信息

类似于粒子-反粒子,斯格明子与反斯格明子具有相反的拓扑序参量.斯格明子-反斯格明子耦合态具有特殊的拓扑磁电特性,例如霍尔天平动力学,可以用来开发赛道存储等新型拓扑自旋电子学器件.本文结合理论计算与实空间观测手段,在一类焦点材料S_(4)对称FeNiPdP中报道了一种新型三维斯格明子-反斯格明子耦合态.通过磁布洛赫点四极子,斯格明子与反斯格明子能在厚度方向上缝合并堆垛在一起形成稳定的三维管状结构.作者提出了一种高效分辨斯格明子-反斯格明子管和斯格明子管的判据,澄清了潜在的磁结构分辨疑云,重新定义了该系列材料的应用前景.研究结果建立了S_(4)对称斯格明子材料的完整三维磁结构模型,提供了一种斯格明子-反斯格明子耦合新方案,将有力推动拓扑磁性理论的发展和拓扑自旋电子学器件的构筑.

关键词：布洛赫四极子磁电特性磁结构管状结构观测手段厚度方向

Amplification of in-plane seismic ground motion by group cavities in layered half-space (Ⅰ)

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Earthquake Science 2012年第4期25卷 275-285页

作者： Jianwen Liang Ji Zhang Zhenning Ba Department of civil engineering Tianjin University Tianjin Key laboratory of civil engineering structures and New materials

Amplification of in-plane seismic ground motion by underground group cavities in layered half-space is studied both in frequency domain and time domain by using indirect boundary element method （IBEM）, and the effect of cavity interval and spectrum of incident waves on the amplification are studied by numerical examples. It is shown that there may be large interaction between cavities, and group cavities with certain intervals may have significant amplification to seismic ground motion. The amplification of PGA （peak ground acceleration） and its PRS （peak response spectrum） can be increased up to 45.2% and 84.4%, for an example site in Tianjin, under the excitation of Taft wave and E1 Centro wave; and group cavities may also affect the spectra of the seismic ground motion. It is suggested that the effect of underground group cavities on design seismic ground motion should be considered.

关键词： underground group cavity amplification in-plane seismic ground motion time domain frequency domain indirect boundary element method （IBEM）

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Experimental Study on Vortex-Induced Vibration of Marine Riser Model with Coupling Interference Effect Under Combined Internal and External Flow

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中国海洋工程:英文版 2023年第4期37卷 673-684页

作者： REN Xiao-hui LI Peng CHEN Xin WANG Ye-shuo LIU Zhen HAO Lian-hong WANG Yu HUANG Yi-jie College of Architecture and civil engineering Shandong University of Science and TechnologyQingdao 266590China Qingdao Key laboratory of Marine civil engineering materials and structures Qingdao 266590China School of Petroleum engineering China University of Petroleum(East China)Qingdao 266580China

A partition model of interference efficiency was constructed to study the coupling interference effect under combined internal and external flow.The concept of“internal flow efficiency”,“velocity ratio”and“interference efficiency”were introduced to quantify the effect of internal flow and interference,and reveal the coupling mechanism among internal flow,external flow and interference effect.The results showed that the dynamic response of risers under variable angles was significantly different after considering the effect of internal flow.When the external flow velocity was smaller than 0.25 m/s,the vibration of risers was promoted by the internal flow.With the increase of external flow velocity,the effect of internal flow was weakened and the dynamic response of riser mainly depended on the external flow and interference effect.Under the effect of different internal flow,the interference efficiency had similar change trend.The interference effect amplified the complex secondary flow effect inside the riser,making the dynamic response of riser complex and random.In this paper,the overlap area and subdivision criterion of interference effect were constructed within the range of experimental velocity ratio,and the change curve of interference efficiency was obtained with an average meaning,which may have important practical meaning.

关键词： marine riser vortex-induced vibration internal flow interference effect interference efficiency internal flow efficiency

Microstructural Evolution Mechanism of C-(A)-S-H Gel in Portland Cement Pastes Affected by Sulfate Ions

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Journal of Wuhan University of Technology(materials Science) 2018年第3期33卷 639-647页

作者：张高展 ZHANG Xiaojia 丁庆军 HOU Dongshuai LIU Kaiwei Advanced Building materials Key laboratory of anhui Province Anhui Jianzhu University School of materials Science and engineering Wuhan University of Technology Department of civil engineering Qingdao Technological University

The microstructural evolution of C-（A）-S-H gel in Portland cement pastes immersed in pure water and 5.0 wt% Na2SO4 solution for different ages was comparatively investigated, by means of ^（29） Si NMR spectroscopy, and SEM-EDS analysis. Additionally, molecular dynamics simulation was performed to study the aluminum coordination status and interaction of sulfate ions in C-（A）-S-H gel. The results showed significant changes in the microstructural evolution of C-（A）-S-H gel in Portland cement paste. Sulfate attack has decalcifying and dealuminizing effect on C-（A）-S-H gel which is evident from increase in mean chain length（MCL） and decrease in Ca/Si ＆ Al[4]/Si ratios of C-（A）-S-H gel. Additionally, Molecular dynamics simulation proves that Al[4] substituted in silicate chains of C-（A）-S-H gel is thermodynamically metastable, which may explain its migration from the silicate chains and transformation to Al[6], thus lowering the Al[4]/Si ratio of C-（A）-S-H gel. SO4^（2-）ions can carry the interfacial Ca^（2＋） ions into the pore solution by the diffusion-absorption-desorption process, which unravels the mechanism of sulfate attack on C-（A）-S-H gel.

关键词： sulfate attack portland cement paste C-（A）-S-H gel microstructure interaction mechanism

Effect of Magnesium on the C-S-H Nanostructure Evolution and Aluminate Phases Transition in Cement-Slag Blend

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Journal of Wuhan University of Technology(materials Science) 2018年第1期33卷 108-116页

作者：丁庆军 YANG Jun 张高展 HOU Dongshuai School of materials Science and engineering Wuhan University of Technology Advanced Building materials Key laboratory of anhui Province Anhui Jianzhu University Department of civil engineering Qingdao Technological University

The microstructural study was conducted on cement and cement-slag pastes immersed in different concentrations of Mg（NO3）2 solutions utilizing ^29Si, ^27Al NMR spectroscopy and XRD techniques. The results show that the hydration of both the cement and cement-slag pastes is delayed when the pastes are cured in Mg（NO3）2 solutions as compared to the pastes cured in water. Moreover, Mg^2＋ ions also exhibit an decalcifying and dealuminizing effect on the C-A-S-H in cement and cement-slag pastes, and thereby decrease Ca/Si and Al[4]/Si ratios of the C-A-S-H. The dealuminization of C-A-S-H is mitigated for cement-slag paste as compared to pure cement paste. The depolymerized calcium and aluminum ions from C-A-S-H gel mainly enter the pore solution to maintain the pH value and form Al^[6] in TAH, respectively. On the other hand, Mg^2＋ ions exert an impact on the intra-transition between Al^[6] species, from AFm and hydrogarnet to hydrotalcite-like phase. NO3^-ions are interstratified in the layered Mg-Al structure and formed nitrated hydrotalcite-like phase（Mg1-xAlx（OH）2（NO3）x·nH2O）. Results from both ^27Al NMR and XRD data show that ettringite seems not to react with Mg^2＋ ions.

关键词： ^29Si and ^27Al NMR magnesium ion C-A-S-H microstructure aluminate phases transition hydration slag incorporation

3D Diffraction of obliquely incident SH waves by twin infinitely long cylindrical cavities in layered poroelastic half-space

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Earthquake Science 2013年第6期26卷 395-406页

作者： Jianwen Liang Bing Han Zhenning Ba Department of civil engineering Tianjin University Tianjin Key laboratory of civil engineering structures & New materials

Abstract This paper studies three-dimensional diffraction of obliquely incident plane SH waves by twin infinitely long cylindrical cavities in layered poroelastic half-space using indirect boundary element method. The approach is validated by comparison with the literature, and the effects of cavity interval, incident frequency, and boundary drainage condition on the diffraction are studied through numerical examples. It is shown that, the interaction between two cavities is significant and surface displacement peaks become large when two cavities are close, and the surface displacement may be significantly amplified by twin cavities, and the influence range with large amplification can be as wide as 40 times of the cavity radius. Surface displacements in dry poroelastic case and saturated poroelastic cases with drained and undrained boundaries are evidently different under certain circumstances, and the differences may be much larger than those in the free-field response.

关键词： Diffraction Infinitely long cylindricalcavities Obliquely incidence Layered poroelastichalf-space Indirect boundary element method（IBEM） Amplification Plane SH waves