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Journal of Central South University 2015年第8期22卷 3059-3068页

作者： Esmail Aflaki Alborz Hajiannia civil and environmental engineering department Amirkabir University of Technology

The present work ascertains the feasibility of oil residue treatment for stabilizing wind-blown sand dunes. Various combinations of natural collapsible saline from the Jandaq desert of Iran and oil residue from distillation towers of Iranian refineries were tested in laboratory experiments. Stabilized sands were evaluated in terms of geotechnical properties, permeability, and oil retention characteristics(i.e. bonding mechanisms, leaching and migrating behaviour of oil residue from the stabilized sands). Since the presence of oil residue in soils can pose an environmental threat, the optimum retention capacity of the stabilized sands is of critical concern. Relative to sand that was not augmented with oil residue, specimens made of 7% oil residues had the highest compressive strength, significantly higher cohesion and load bearing capacity, and considerably lower permeability. The effect of distilled water, saline water and municipal sewage on prepared specimens were also evaluated.

关键词： stabilization environment residual oil sand dune sewage

Aligned Ion Conduction Pathway of Polyrotaxane‑Based Electrolyte with Dispersed Hydrophobic Chains for Solid‑State Lithium–Oxygen Batteries

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Nano-Micro Letters 2025年第2期17卷 169-186页

作者： Bitgaram Kim Myeong‑Chang Sung Gwang‑Hee Lee Byoungjoon Hwang Sojung Seo Ji‑Hun Seo Dong‑Wan Kim department of Materials Science and engineering Korea University145 Anam‑RoSeongbuk‑GuSeoul 02841Republic of Korea School of civil Environmental and Architectural EngineeringKorea University145 Anam‑RoSeongbuk‑GuSeoul 02841Republic of Korea Materials Science and Chemical engineering Center Institute for Advanced Engineering(IAE)Yongin 17180Republic of Korea

A critical challenge hindering the practical application of lithium–oxygen batteries(LOBs)is the inevitable problems associated with liquid electrolytes,such as evaporation and safety *** study addresses these problems by proposing a modified polyrotaxane(mPR)-based solid polymer electrolyte(SPE)design that simultaneously mitigates solvent-related problems and improves ***-SPE exhibits high ion conductivity(2.8×10^(−3)S cm^(−1)at 25℃)through aligned ion conduction pathways and provides electrode protection ability through hydrophobic chain *** this mPR-SPE into solid-state LOBs resulted in stable potentials over 300 *** situ Raman spectroscopy reveals the presence of an LiO_(2)intermediate alongside Li_(2)O_(2)during oxygen *** situ X-ray diffraction confirm the ability of the SPE to hinder the permeation of oxygen and moisture,as demonstrated by the air permeability *** present study suggests that maintaining a low residual solvent while achieving high ionic conductivity is crucial for restricting the sub-reactions of solid-state LOBs.

关键词： Solid polymer electrolyte Lithium-oxygen batteries Polyrotaxane ion conductivity Hydrophobic chain

Statistical determination of significant curved I-girder bridge seismic response parameters

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Earthquake engineering and engineering Vibration 2013年第2期12卷 251-260页

作者： Junwon Seo department of civil Construction & Environmental EngineeringIowa State University

Curved steel bridges are commonly used at interchanges in transportation networks and more of these structures continue to be designed and built in the United States. Though the use of these bridges continues to increase in locations that experience high seismicity, the effects of curvature and other parameters on their seismic behaviors have been neglected in current risk assessment tools. These tools can evaluate the seismic vulnerability of a transportation network using fragility curves. One critical component of fragility curve development for curved steel bridges is the completion of sensitivity analyses that help identify influential parameters related to their seismic response. In this study, an accessible inventory of existing curved steel girder bridges located primarily in the Mid-Atlantic United States （MAUS） was used to establish statistical characteristics used as inputs for a seismic sensitivity study. Critical seismic response quantities were captured using 3D nonlinear finite element models. Influential parameters from these quantities were identified using statistical tools that incorporate experimental Plackett-Burman Design （PBD）, which included Pareto optimal plots and prediction profiler techniques. The findings revealed that the potential variation in the influential parameters included number of spans, radius of curvature, maximum span length, girder spacing, and cross-frame spacing. These parameters showed varying levels of influence on the critical bridge response.

关键词： Plackett-Burman design pareto plot prediction profiler statistical characteristics steel bridge seismic response

Novel Methodologies for Preventing Crack Propagation in Steel Gas Pipelines Considering the Temperature Effect

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Structural Durability & Health Monitoring 2025年第1期19卷 1-23页

作者： Nurlan Zhangabay Ulzhan Ibraimova Marco Bonopera Ulanbator Suleimenov Konstantin Avramov Maryna Chernobryvko Aigerim Yessengali department of Architecture and Urban Planning Mukhtar Auezov South Kazakhstan UniversityShymkent160012Kazakhstan department of Industrial civil and Road construction Mukhtar Auezov South Kazakhstan UniversityShymkent160012Kazakhstan Mechanics Sound&Vibration LaboratoryDepartment of Civil EngineeringCollege of EngineeringNational Taiwan UniversityTaipei10617Taiwan department of Reability&Dynamic Strength A.Pidhornyi Institute of Mechanical Engineering Problems of National Academy of Sciences of UkraineKharkiv61046Ukraine

Using the software ANSYS-19.2/Explicit Dynamics,this study performedﬁnite-element modeling of the large-diameter steel pipeline cross-section for the Beineu-Bozoy-Shymkent gas pipeline with a non-through straight crack,strengthened by steel wire *** effects of the thread tensile force of the steel winding in the form of single rings at the crack edges and the wires with different winding diameters and pitches were also *** results showed that the strengthening was preferably executed at a minimum value of the thread tensile force,which was 6.4%more effective than that at its maximum *** analysis of the inﬂuence of the winding dia-meters showed that the equivalent stresses increased by 32%from the beginning of the crack growth until the wire *** increment in winding diameter decelerated the disclosure of the edge crack and reduced its length by 8.2%.The analysis of the inﬂuence of the winding pitch showed that decreasing the distance between the winding turns also led to a 33.6%reduction in the length of the straight crack and a 7.9%reduction in the maximum stres-ses on the strengthened pipeline *** analysis of the temperature effect on the pipeline material,within a range from-40℃ to+50℃,resulted in a crack length change of up to 5.8%.As the temperature dropped,the crack length *** such a temperature range,the maximum stresses were observed along the cen-tral area of the crack,which were equal to 413 MPa at+50℃ and 440 MPa at-40℃.The results also showed that the presence of the steel winding in the pipeline signiﬁcantly reduced the length of crack propagation up to 8.4 times,depending on the temperature effect and design parameters of *** work integrated the existing methods for crack localization along steel gas pipelines.

关键词： Crack propagation ﬁnite-element internal pressure prestressing steel gas pipeline temperature effect

The difference of morphological characteristics and population structure in PAO and DPAO granular sludges

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Journal of environmental Sciences 2019年第2期31卷 388-402页

作者： Geumhee Yun Hansaem Lee Yongsuk Hong Sungpyo Kim Glen T.Daigger Zuwhan Yun department of environmental engineering Korea University Hyundai engineering & construction Co. Ltd. department of civil and environmental engineering University of Michigan

We examined how long-term operation of anaerobic–oxic and anaerobic–anoxic sequencing batch reactors(SBRs) affects the enhanced biological phosphorus removal(EBPR)performance and sludge characteristics. The microbial characteristics of phosphorus accumulating organism(PAO) and denitrifying PAO(DPAO) sludge were also analyzed through a quantitative analysis of microbial community structure. Compared with the initial stage of operation characterized by unstable EBPR, both PAO and DPAO SBR produced a stable EBPR performance after about 100-day operation. From day 200 days(DPAO SBR)and 250 days(PAO SBR) onward, sludge granulation was observed, and the average granule size of DPAO SBR was approximately 5 times larger than that of PAO SBR. The DPAO granular sludge contained mainly rod-type microbes, whereas the PAO granular sludge contained coccus-type microbes. Fluorescence in situ hybridization analysis revealed that a high ratio of Accumulibacter clade I was found only in DPAO SBR, revealing the important role of this organism in the denitrifying EBPR system. A pyrosequencing analysis showed that Accumulibacter phosphatis was present in PAO sludge at a high proportion of 6%,whereas it rarely observed in DPAO sludge. Dechloromonas was observed in both PAO sludge(3.3%) and DPAO sludge(3.2%), confirming that this organism can use both O_2 and NO_3^- as electron acceptors. Further, Thauera spp. was identified to have a new possibility as denitrifier capable of phosphorous uptake under anoxic condition.

关键词： Accumulibacter phosphatis Dechloromonas Granulation Pyrosequencing Thauera

Experimental evaluation of the effect of storm movement on peak discharge

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International Journal of Sediment Research 2015年第2期30卷 167-177页

作者： Jin Liang Charles S.Melching department of civil Construction and Environmental EngineeringMarquette University

The hypothesis that downstream moving storms with storm length less than watershed length（L;/L< 1.0） magnify the peak discharges as indicated by kinematic-wave models in previous studies was evaluated in an analysis of the dimensionless peak discharge and dimensionless storm *** unpublished experimental data collected for a V-shaped watershed in the Watershed Experimentation System（WES） at the University of Illinois at Urbana-Champaign,were used in comparison with the simulation results of a kinematic-wave *** is found that downstream moving storms with L;/L < 1.0 increase the peak discharges to a limited extent compared to stationary storms,and the kinematic-wave model overstates the increase in the peak flows resulting from downstream moving storms with L;/L < *** evaluate the importance of the backwater effects in the experimental watershed,the accuracy of kinematic-wave and dynamic-wave models for the simulation of surface runoff resulting from upstream and downstream moving storms was evaluated utilizing the same experimental *** kinematic-wave model simulates the upstream moving storms pretty well,***-Sutcliffe coefficient of model fit efficiency equal to 0.948 and 0.831 for storms lengths equal to and not equal to the watershed length,***,the kinematic wave model substantially overestimates the peak discharge of downstream moving storms,and yields generally poorer fits than for upstream moving storm,*** equal to 0.867 and 0.674 for storms with lengths equal to and not equal to the watershed length,*** dynamic-wave model simulates the downstream moving storms pretty well,*** equal to 0.843 and 0.879 for storms with lengths equal to and not equal to the watershed length,respectively,indicating backwater significantly affects runoff for even this simple experimental *** that storm movement did not substantially magnify peak discharge,the assumption of stationary storms made

关键词： Moving storms Kinematic-wave Dynamic-wave Experimental data Dimensional analysis

Cell surface-expression of the phosphate-binding protein PstS:System development,characterization,and evaluation for phosphorus removal and recovery

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Journal of environmental Sciences 2020年第6期32卷 129-140页

作者： Faten B.Hussein Kaushik Venkiteshwaran Brooke K.Mayer department of civil Construction and Environmental EngineeringMarquette UniversityMilwaukeeWI53233USA

Simultaneous overabundance and scarcity of inorganic phosphate(Pi)is a critical issue driving the development of innovative water/wastewater treatment technologies that not only facilitate Pi removal to prevent eutrophication,but also recover Pi for agricultural ***,a cell-surface expressed high-affinity phosphate binding protein(PstS)system was developed,and its Pi capture and release potential was *** was genetically modified to express PstS on its outer membrane using the ice nucleation protein(INP)as an anchoring *** of protein expression and localization were performed utilizing SDS-polyacrylamide gel electrophoresis(SDS-PAGE),western blot,and outer membrane separation *** surface characterization was investigated through acid-base titration,X-ray photoelectron spectroscopy(XPS),and Fourier transform infrared spectroscopy(FTIR).These tests provided information on the macromolecular structure and composition of the bacteria surface as well as the proton-exchange properties of the surface functional groups(i.e.,pKa values).Phosphate desorption and adsorption batch experiments were conducted to evaluate the effects of temperature,pH,and ionic strength on phosphate capture and *** PstS surface-displayed cells demonstrated greater potential to release and capture phosphate compared to non-modified *** temperatures up to 40℃,basic pH conditions(pH=10.5),and higher ionic strength up to 1.0 mol/L KCl promoted 20%-50%higher phosphate release.

关键词： Phosphorus recovery Water treatment Eutrophication Surface-expression PstS protein E.coli bacteria Phosphate

construction quality acceptance performance-related specifications for chip seals

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Journal of Traffic and Transportation engineering(English Edition) 2019年第4期6卷 337-348页

作者： Javon Adams Cassie Castorena Y.Richard Kim department of civil Construction and Environmental Engineering North Carolina State University

The research described herein details the establishment of a framework for construction quality acceptance performance-related specifications(PRS) for chip seal surface treatments. This paper establishes acceptance quality characteristics(AQCs) and relationships between the AQCs and related chip seal performance measures. This work is a critical step in developing PRS for constructed chip seal treatments and establishing suitable guidelines for the PRS. The main objective of this paper is to determine appropriate test methods to evaluate each defined AQC. The relationships that are established between the AQCs and chip seal performance are used to define performance ranges and threshold values for a particular performance measure. These performance ranges and threshold values then can be used to define pay factors for the constructed chip seal section. The threshold values and pay factors for each AQC described herein are preliminary recommendations and require further validation prior to implementation. However, this research demonstrates how these PRS would be utilized to ensure acceptable chip seal construction quality in the *** developed construction quality acceptance PRS framework uses the percent within limits(PWL) concept to determine whether a chip seal lot passes the PRS threshold values and whether the contractor receives full pay, is subject to a pay penalty, or fails the construction PRS and must correct the chip seal within the first year in service, which constitutes the typical warranty period for contracted chip seal ***, recommendations are made as to the next steps in the development and validation of these construction quality acceptance PRS that are needed for implementation by contractors and state roadway maintenance agencies.

关键词： Performance-related specifications(PRS) Chip seal construction Quality assurance Percent within limits

Evaluation of accelerated deterioration in NAPTF flexible test pavements

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2008年第9期9卷 1157-1166页

作者： Kasthurirangan GOPALAKRISHNAN department of civil Construction and Environmental EngineeringIowa State UniversityIA 50011USA

Previous research studies have successfully demonstrated the use of artificial neural network (ANN) models for predicting critical structural responses and layer moduli of highway flexible pavements. The primary objective of this study was to develop an ANN-based approach for backcalculation of pavement moduli based on heavy weight deflectometer (HWD) test data, especially in the analysis of airport flexible pavements subjected to new generation aircraft (NGA). Two medium-strength sub-grade flexible test sections, at the National Airport Pavement Test Facility (NAPTF), were modeled using a finite element (FE) based pavement analysis program, which can consider the non-linear stress-dependent behavior of pavement geomaterials. A multi-layer, feed-forward network which uses an error-backpropagation algorithm was trained to approximate the HWD back-calculation function using the FE program generated synthetic database. At the NAPTF, test sections were subjected to Boeing 777 (B777) trafficking on one lane and Boeing 747 (B747) trafficking on the other lane using a test machine. To monitor the effect of traffic and climatic variations on pavement structural responses, HWD tests were conducted on the trafficked lanes and on the untrafficked centerline of test sections as trafficking progressed. The trained ANN models were successfully applied on the actual HWD test data acquired at the NAPTF to predict the asphalt concrete moduli and non-linear subgrade moduli of the me-dium-strength subgrade flexible test sections.

关键词： Airport flexible pavements Heavy weight deflectometer (HWD) Artificial neural networks (ANN) Elastic moduli New generation aircraft (NGA)

Resilient modulus prediction of soft low-plasticity Piedmont residual soil using dynamic cone penetrometer

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Journal of Rock Mechanics and Geotechnical engineering 2018年第2期10卷 323-332页

作者： S.Hamed Mousavi Mohammed A.Gabr Roy H.Borden department of civil Construction and Environmental Engineering North Carolina State University

Dynamic cone penetrometer（DCP） has been used for decades to estimate the shear strength and stiffness properties of the subgrade soils. There are several empirical correlations in the literature to predict the resilient modulus values at only a specific stress state from DCP data, corresponding to the predefined thicknesses of pavement layers（a 50 mm asphalt wearing course, a 100 mm asphalt binder course and a200 mm aggregate base course）. In this study, field-measured DCP data were utilized to estimate the resilient modulus of low-plasticity subgrade Piedmont residual soil. Piedmont residual soils are in-place weathered soils from igneous and metamorphic rocks, as opposed to transported or compacted *** the existing empirical correlations might not be applicable for these soils. An experimental program was conducted incorporating field DCP and laboratory resilient modulus tests on "undisturbed" soil specimens. The DCP tests were carried out at various locations in four test sections to evaluate subgrade stiffness variation laterally and with depth. Laboratory resilient modulus test results were analyzed in the context of the mechanistic-empirical pavement design guide（MEPDG） recommended universal constitutive model. A new approach for predicting the resilient modulus from DCP by estimating MEPDG constitutive model coefficients（k;,k;and k;） was developed through statistical analyses. The new model is capable of not only taking into account the in situ soil condition on the basis of field measurements,but also representing the resilient modulus at any stress state which addresses a limitation with existing empirical DCP models and its applicability for a specific case. Validation of the model is demonstrated by using data that were not used for model development, as well as data reported in the literature.

关键词： Dynamic cone penetrometer(DCP) Resilient modulus Mechanistic-empirical pavement design guide(MEPDG) Residual soils Subgrade soils