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Journal of Mountain Science 2020年第12期17卷 2929-2941页

作者： ZHANG Ting-yu MAO Zhong-an WANG Tao Shaanxi Provincial Land engineering construction Group Land Survey Planning and Design Institute co. Ltd.Xi'an710075China

Landslide susceptibility mapping is significant for landslide *** approaches have been used for landslide susceptibility prediction,however,their performances are *** study co.structed a hybrid model,namely box co.nting dimension-based kernel logistic regression model,which uses fractal dimension calculated by box co.nting method as input data based on grid cells mapping unit and terrain mapping *** performance of this model was evaluated in the application in Zhidan co.nty,Shaanxi Province,***,a total of 221 landslides were identified and mapped,and 11 landslide predisposing factors were ***,the landslide susceptibility maps(LSMs) of the study area were obtained by co.structing the model on two different mapping ***,the results were evaluated with five statistical indexes,sensitivity,specificity,positive predictive value(PPV),negative predictive value(NPV) and *** statistical indexes of the model obtained on the terrain mapping unit were larger than those based on grid cells mapping *** training and validation datasets,the area under the receiver operating characteristic curve(AUC) of the model based on terrain mapping unit were 0.9374 and 0.9527,respectively,indicating that establishing this model on the terrain mapping unit was advantageous in the study *** results show that the fractal dimension improves the prediction ability of the kernel logistic *** addition,the terrain mapping unit is a more promising mapping unit in Loess areas.

关键词： Kernel logistic regression model Landslide susceptibility GIS Fractal dimension

Tunnel face stability and ground settlement in pressurized shield tunnelling

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Journal of Central South University 2014年第4期21卷 1600-1606页

作者：苏艺汪国锋周庆宏 Beijing Railway construction and Management co. Ltd. School of engineering and Technology China University of Geosciences (Beijing) Haikou Forest Farm

An analysis of the stability of large-diameter circular tunnels and ground settlement during tunnelling by a pressurized shield was presented. An innovative three-dimensional translational multi-block failure mechanism was proposed to determine the face support pressure of large-shield tunnelling. co.pared with the currently available mechanisms, the proposed mechanism has two unique features:(1) the supporting pressure applied to the tunnel face is assumed to have a non-uniform rather than uniform distribution, and(2) the method takes into acco.nt the entire circular excavation face instead of merely an inscribed ellipse. Based on the discrete element method, a numerical simulation of the Shanghai Yangtze River Tunnel was carried out using the Particle Flow co.e in two dimensions. The immediate ground movement during excavation, as well as the behaviour of the excavation face, the shield movement, and the excavated area, was co.sidered before modelling the excavation process.

关键词： settlement large-diameter shield tunnel three-dimensional failure mechanism

Electroco.gulation co.pled with electrooxidation for the simultaneous treatment of multiple pollutants in co.taminated sediments

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Journal of Environmental Sciences 2023年第2期124卷 89-97页

作者： Qingjun Zeng Yifan Zhang Pingshan Chen Yuting He co.gli Yi Chunhua Feng Fourth Harbor engineering Institute co. Ltd.China Communications Construction Co.Ltd.Guangzhou 510230China Key Laboratory of Environmental Protection&Safety of co.munication Foundation engineering China Communications Construction Co.Ltd.Guangzhou 510230China The Key Lab of Pollution co.trol and Eco.ystem Restoration in Industry Clusters Ministry of EducationSchool of Environment and EnergySouth China University of TechnologyGuangzhou 510006China

In situ and simultaneous remediation of a variety of pollutants in sediments remains a *** this study,we report that the co.bination of electroco.gulation(EC)and electrooxidation(EO)is efficient in the immobilization of phosphorus and heavymetals and in the oxidation of ammonium and toxic *** integratedmixed metal oxide(MMO)/Fe anode system allowed the facile removal of ammonium and phosphorus in the overlying water(99% of 10 mg/L NH_(4)^(+)-N and 95% of 10 mg/L P disappeared in 15 and 30 min,respectively).co.pared with the co.trols of the single Fe anode and single MMO anode systems,the dual MMO/Fe anode system significantly improved the removal of phenanthrene and promoted the transition of Pb and Cu from the mobile species to the immobile *** co.centrations of Pb and Cu in the toxicity characteristic leaching procedure extracts were reduced by 99%and 97% after an 8 hr *** tests with four real polluted samples indicated that substantial proportions of acid-soluble fraction Pb and Cu were reduced(30%-31% for Pb and 16%–23% for Cu),and the amounts of total organic carbon and NH_(4)^(+)-N decreased by 56%–71% and 32%–63%,*** was proposed that the in situ electrogenerated Fe(II)at the Fe anode and the active oxygen/chlorine species at the MMO anode are co.ducive to outstanding performance in the co.treatment of multiple *** results suggest that the EC/EO method is a powerful technology for the in situ remediation of sediments co.taminated with different pollutants.

关键词： In situ sediment remediation Electroco.gulation Electrooxidation Stabilization of heavy metals Ammonia oxidation Removal of polycyclic aromatic hydrocarbons

Development of Steel Slag-Based Solidification/Stabilization Materials for High Moisture co.tent Soil

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Journal of Renewable Materials 2022年第3期10卷 735-749页

作者： Yu Jia Sudong Hua Liying Qian Xiaojian Ren Jie Zuo Yanfang Zhang co.lege of Materials Science and engineering Nanjing Tech UniversityNanjing210009China Jangsu Yonggang Group co. Ltd.Suzhou215628China China construction Installaction engineering co. Ltd.Nanjing210023China

To solve the problems of high moisture co.tent,high visco.ity,and poor engineering mechanical properties of soil,this paper using with steel slag(SS)and desulfurization ash(DS)as initial raw materials,realizing the co.p-erative treatment of solid waste and solidification of silt *** synergistic utilization of SS and DS can reduce the production co.t of curing agent and promote its own *** to blended cement of various SS co.tents and inspected co.pressive strength performances,the most suitable raw materials ratio was *** best formula for this curing agent is cement:steel slag=3:7 with 5%DS,and its 28-day co.pressive strength can reach 30 *** experiment shows that the effect of DS and Na_(2)SO_(4) reagent with the same quality on early co.pressive strength improvement of cement and SS system is not much *** this study,the mineral co.position and microstructure of different gel system blocks were characterized by XRD,SEM and EDX,and a large number of webbed structures were found in the SEM test,which was not seen in previous ***,unco.fined co.pressive strength(UCS),water resistance,and toxic characteristic leaching procedure(TCLP)were used to evaluate silt solidified soil *** results demonstrated that the solidified silt co.ld meet not only the standard of general subgrade;but also has a partial stabilization effect of heavy metal ions.

关键词： Steel slag desulfurization ash high moisture co.tent soil synergistic effect strength stabilized soil

Research on an innovative structure of an open-ribbed steel-ultra-high performance co.crete co.posite bridge deck

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Frontiers of Structural and Civil engineering 2024年第5期18卷 716-730页

作者： Xudong SHAO Xuan SUN Deqiang ZOU Junhui CAO Chuanqi YANG School of Civil engineering Hunan UniversityKey Laboratory for Wind and Bridge Engineering of Hunan ProvinceChangsha 410082China China construction Fifth engineering Division co. Ltd.Changsha 410004China

To co.pletely solve the problem of fatigue cracking issue of orthotropic steel bridge decks(OSDs),the authors proposed a steel–ultra-high performance co.crete(UHPC)lightweight co.posite deck(LWCD)with closed ribs in *** on the successful application of that LWCD,an adaptation inco.porating an innovative co.posite deck structure,i.e.,the hot-rolled section steel–UHPC co.posite deck with open ribs(SSD)is proposed in this paper,aiming to simplify the fabrication process as well as to reduce the co.t of *** on a long-span cable-stayed bridge,a design scheme is proposed and is co.pared with the co.ventional OSD ***,a finite element(FE)calculation is co.ducted to reflect both the global and local behavior of the SSD scheme,and it is found that the peaked stresses in the SSD co.ponents are less than the co.responding allowable values.A static test is performed for an SSD strip specimen to understand the anti-cracking behavior of the UHPC layer under negative bending *** static test results indicate that the UHPC layer exhibited a satisfactory tensile toughness,the UHPC tensile strength obtained from the test is 1.8 times the calculated stress by the FE model of the real *** addition,the fatigue stresses of typical fatigue-prone details in the SSD are calculated and evaluated,and the influences of key design parameters on the fatigue performance of the SSD are *** to the fatigue results,the peaked stress ranges for all of the 10 fatigue-prone details are within the co.responding co.stant amplitude fatigue *** a fatigue test is carried out for another SSD strip specimen to explore the fatigue behavior of the fillet weld between the longitudinal and transverse *** specimen failed at the fillet weld after equivalent 47.5 million cycles of loading under the design fatigue stress range,indicating that the fatigue performance of the SSD co.ld meet the fatigue design *** calculations and experim

关键词： steel-ultra-high performance co.crete co.posite deck open rib strip model test static and fatigue performance orthotropic steel deck

Uplift mechanism for a shallow-buried structure in liquefi able sand subjected to seismic load: centrifuge model test and DEM modeling

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Earthquake engineering and engineering Vibration 2014年第2期13卷 203-214页

作者： Zhou Jian Wang Zihan Chen Xiaoliang Zhang Jiao Department of Geotechnical engineering Tongji University School of Civil engineering Hebei University of Technology Hangzhou Municipal construction Group co. LTD School of Civil engineering and Transportation Shanghai Technical College of Urban Management

Based on a centrifuge model test and distinct element method(DEM), this study provides new insights into the uplift response of a shallow-buried structure and the liquefaction mechanism for saturated sand around the structure under seismic action. In the centrifuge test, a high-speed microsco.ic camera was installed in the structure model, by which the movements of particles around the structure were monitored. Then, a two-dimensional digital image processing technology was used to analyze the microstructure of saturated sand during the shaking event. Herein, a numerical simulation of the centrifuge experiment was co.ducted using a two-phase(solid and fl uid) fully co.pled distinct element co.e. This co.e inco.porates a particle-fl uid co.pling model by means of a "fi xed co.rse-grid" fl uid scheme in PFC3D(Particle Flow co.e in Three Dimensions), with the modeling parameters partially calibrated based on earlier studies. The physical and numerical models both indicate the uplifts of the shallow-buried structure and the sharp rise in excess pore pressure. The co.responding micro-scale responses and explanations are provided. Overall, the uplift response of an underground structure and the occurrence of liquefaction in saturated sand are predicted successfully by DEM modeling. However, the dynamic responses during the shaking cannot be modeled accurately due to the restricted co.puter power.

关键词： centrifuge modeling underground structure liquefaction distinct element method saturated sand

Development of a Soil Stabilizer for Road Subgrade Based on Original Phosphogypsum

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Journal of Renewable Materials 2021年第2期9卷 253-268页

作者： Zenghuan Gu Aiguo Fang Sudong Hua Qingzhou Zhao Lidong Sun Fan Xia Liying Qian Xiaojian Ren co.lege of Materials Science and engineering Nanjing Tech UniversityNanjing210009China China construction Installation engineering co. Ltd.Nanjing210023China Jiangsu YongGang Group co. Ltd.Suzhou215628China

The research used industrial by-products original phosphogypsum(PG)as the main raw material,slag(SG)and Portland cement(PC)as auxiliary materials,and the optimal additive amount was determined acco.ding to the co.pressive strength value of the *** evaluate the water resistance and volume stability of the samples,and determine the best formula for new roadbed stabilized *** results showed that when the weight ratio of PG,slag and cement was OPG:SG:PC=6:3:1,and mixed with 5%micro silica fume(MSF)and 3‰hydroxypropyl methyl cellulose(HPMC),the sample’s co.prehensive performance was the best,specifically,the sample’s co.pressive strength in 60 days reached 28.8 MPa,the softening co.fficient reached 0.9,and the expansion rate was stable at about−0.2%.In addition,the mechanism of action of enhancers MSF and HPMC was analyzed acco.ding to use Vicat device,X-ray diffractometer and scanning electron *** best formula SP3GH3 has the best curing effect on *** 28-day unco.fined co.pressive strength(UCS)of the sample reached 2.4 MPa,the expansion rate was less than 0.09%,and the water stability co.fficient was above 0.79,which was higher than that of the samples cured by traditional cement and lime during the same period.

关键词： Original phosphogypsum subgrade stabilized material co.pressive strength softening co.fficient expansion rate

Short-term tunnel-settlement prediction based on Bayesian wavelet:a probability analysis method

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Journal of zhejiang University-Science A(Applied Physics & engineering) 2023年第11期24卷 960-977页

作者： Yang DING Xiaowei YE Zhi DING Gang WEI Yunliang CUI Zhen HAN Tao JIN Key Laboratory of Safe construction and Intelligent Maintenance for Urban Shield Tunnels of zhejiang Province Hangzhou City UniversityHangzhou 310015China zhejiang engineering Research Center of Intelligent Urban Infrastructure Hangzhou City UniversityHangzhou 310015China Department of Civil engineering Hangzhou City UniversityHangzhou 310015China Department of Civil engineering Zhejiang UniversityHangzhou 310058China Nanjing Metro Operation co. Ltd.Nanjing 210012China

As urbanization accelerates,the metro has beco.e an important means of *** the safety problems caused by metro construction,ground settlement needs to be monitored and predicted regularly,especially when a new metro line crosses an existing *** this paper,we propose a settlement-probability prediction model with a Bayesian emulator(BE)based on the Gaussian prior(GP),that is,a *** addition,co.sidering the distortion characteristics of monitoring data,the data is denoised using wavelet deco.position(WD),so the final prediction model is *** particular,the effects of different prediction ratios and moving windows on prediction performance are explored,and the optimal number of moving windows is *** addition,the predicted value for GPBE based on the original data is co.pared with the predicted value for WD-GPBE based on the denoised *** year of settlement-monitoring data co.lected by a structural health monitoring(SHM)system installed on the Nanjing Metro is used to demonstrate the effectiveness of WDGPBE and GPBE for predicting settlement.

关键词： Metro construction Settlement probability prediction Structural health monitoring(SHM) Wavelet denoising Gaussian prior(GP) Bayesian emulator(BE)

Effects of transient temperature gradient on frost heave of saturated silty clay in an open system

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Research in co.d and Arid Regions 2023年第6期15卷 268-277页

作者： HongYan Ma YuanFang Cui JianQiao Zhang Song Li Song Xu co.lege of Civil engineering Fuzhou UniversityFuzhouFujian 350108China Yunnan construction and Investment Holding co. LtdKunmingYunnan 650501China Ningbo co.munications Planning Institute co. LtdNingboZhejiang 315192China

Frost heave in seasonally frozen regions is a one-dimensional process that co.ld severely damage infrastructure *** state,temperature and water migration are important factors for frost *** work investigated the effects of soil temperature and volumetric water co.tent on the transient frost heave ratio during the freezing of saturated silty clay in an open system and analyzed the relationships between the transient frost heave ratio and freezing rate and between temperature gradient and frost heave *** results show that the frost heave ratio,frost heave rate,and freezing rate are positively co.related with the temperature gradient since the temperature gradient drives the water migration during freezing,indicating the transient temperature gradient co.ld be used to evaluate the frost heave of saturated silty *** transient freezing rate and transient frost heave ratio are logarithmically related to the transient frost heave ratio and transient temperature gradient,*** effects of transient temperature gradient on frost heave are the principal mechanism responsible for different frost heave characteristics and uneven frost heave along a subgrade of the same soil type.

关键词： Saturated silty clay Frost heave Transient temperature gradient Frost heave ratio Frost heave rate

Influence of freeze-thaw damage gradient on stress-strain relationship of stressed co.crete

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Frontiers of Structural and Civil engineering 2023年第9期17卷 1326-1340页

作者： Xiguang LIU Yongjie LEI Yihao SUN Jiali ZHOU Ditao NIU co.lege of Civil engineering Xi’an University of Architecture&TechnologyXi’an 710055China Institute for Interdisciplinary Innovation Research Xi’an 710055China Shaanxi construction engineering Group co. Ltd.Xi’an 710055China XAUAT engineering Technology Co.Ltd.Xi’an 710055China

Freeze-thaw damage gradients lead to non-uniform degradation of co.crete mechanical properties at different depths.A study was co.ducted on the stress-strain relationship of stressed co.crete with focus on the freeze-thaw damage *** effects of relative freeze-thaw depths,number of freeze-thaw cycles(FTCs)and stress ratios on the stress-strain curves of co.crete were *** test results demonstrated that freeze-thaw damage was more severe in the surface layers of co.crete than in the deeper *** relative peak stress and strain of co.crete degraded bilinearly with increasing *** stress-strain relationship of stressed co.crete under FTC was established,and it was found to agree with the experimental results.

关键词： freeze-thaw damage stress ratios stress-strain relationship damage variable