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Application of multi-algorithm ensemble methods in high-dimensional and small-sample data of geotechnical engineering:A case study of swelling pressure of expansive soils

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1896-1917页

作者： Chao Li Lei Wang Jie Li Yang Chen School of Urban Railway Transportation Shanghai University of Engineering ScienceShanghai201620China discipline of civil and infrastructure Engineering RMIT UniversityMelbourne3001Australia School of Naval Architecture and civil Engineering Shanghai Jiao Tong UniversityShanghai200240China

Geotechnical engineering data are usually small-sample and high-dimensional,which brings a lot of challenges in predictive modeling.This paper uses a typical high-dimensional and small-sample swell pressure(P_(s))dataset to explore the possibility of using multi-algorithm hybrid ensemble and dimensionality reduction methods to mitigate the uncertainty of soil parameter prediction.Based on six machine learning(ML)algorithms,the base learner pool is constructed,and four ensemble methods,Stacking(SG),Blending(BG),Voting regression(VR),and Feature weight linear stacking(FWL),are used for the multi-algorithm ensemble.Furthermore,the importance of permutation is used for feature dimensionality reduction to mitigate the impact of weakly correlated variables on predictive modeling.The results show that the proposed methods are superior to traditional prediction models and base ML models,where FWL is more suitable for modeling with small-sample datasets,and dimensionality reduction can simplify the data structure and reduce the adverse impact of the small-sample effect,which points the way to feature selection for predictive modeling.Based on the ensemble methods,the feature importance of the five primary factors affecting P_(s) is the maximum dry density(31.145%),clay fraction(15.876%),swell percent(15.289%),plasticity index(14%),and optimum moisture content(13.69%),the influence of input parameters on P_(s) is also investigated,in line with the findings of the existing literature.

关键词： Expansive soils Swelling pressure Machine learning(ML) Multi-algorithm ensemble Sensitivity analysis

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A novel and promising engineering application of carbon dots:Enhancing the chloride binding performance of cement

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Chinese Chemical Letters 2024年第6期35卷 409-416页

作者： Wu-Jian Long Yang Yu Chuang He Guangdong Provincial Key Laboratory of Durability for Marine civil Engineering Key Lab of Coastal Urban Resilient InfrastructureMOECollege of Civil and Transportation EngineeringShenzhen UniversityShenzhen 518060China

Corrosion of reinforcement induced by chloride invasion is extensively considered as the dominating deterioration mechanism of reinforced concrete(RC)structures,leading to serious safety hazards and tremendous economic losses.However,it still lacks well dispersive and cost-efficient nanomaterials to improve the anti-chloride-corrosion ability of RC structures.Herein,specific carbon dots(CDs)with high dispersity and low cost are deliberately designed,successfully prepared by hydrothermal processing,and then firstly applied to immensely enhance chloride binding performance of cement,thereby contributing to suppressing the corrosion of reinforcement.Specifically,the tailored CDs are composed of the carbon core with highly crystalline sp^(2)C structures and oxygen-containing groups connecting on the carbon core;The typical equilibrium test confirms that with respect to that of the blank cement paste,the chloride binding capacity of cement paste involving 0.2 wt%(by weight of cement)CDs is increased by 109% after 14-day exposure to 3 mol/L Na Cl solution;according to comprehensive analyses of phase compositions,the chloride binding mechanism of CDs-modified cement is rationally attributed to the fact that the incorporation of CDs advances the formation of calcium silicate hydrate(C-S-H)gels and Friedel's salt(Fs),thus enormously enhancing the physically adsorbed and chemically bound chloride ions of cement pastes.This work not only firstly provides a novel high-dispersity and low-cost nanomaterial toward the durability enhancement of RC structures,but also broadens the application of CDs in the field of engineering,conducing to stimulating their industrialization development.

关键词： Carbon dots Chloride binding Cement Chloride binding mechanism Friedel’s salt

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Characterization and Propagation of Historical and Projected Droughts in the Umatilla River Basin, Oregon, USA

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Advances in Atmospheric Sciences 2024年第2期41卷 247-262,I0020-I0028页

作者： Sudip GAUTAM Alok SAMANTARAY Meghna BABBAR-SEBENS Meenu RAMADAS School of civil and Construction Engineering Oregon State UniversityCorvallisOR 97331USA School of infrastructure Indian Institute of TechnologyBhubaneswarOdisha 752050India

Climate change is expected to have long-term impacts on drought and wildfire risks in Oregon as summers continue to become warmer and drier. This paper investigates the projected changes in drought characteristics and drought propagation in the Umatilla River Basin in northeastern Oregon for mid-century(2030–2059) and late-century(2070–2099) climate scenarios. Drought characteristics for projected climates were determined using downscaled CMIP5 climate datasets from ten climate models and Soil and Water Assessment Tool to simulate effects on hydrologic processes. Short-term(three months) drought characteristics(frequency, duration, and severity) were analyzed using four drought indices, including the Standardized Precipitation Index(SPI-3), Standardized Precipitation-Evapotranspiration Index(SPEI-3), Standardized Streamflow Index(SSI-3), and the Standardized Soil Moisture Index(SSMI-3). Results indicate that short-term meteorological droughts are projected to become more prevalent, with up to a 20% increase in the frequency of SPI-3drought events. Short-term hydrological droughts are projected to become more frequent(average increase of 11% in frequency of SSI-3 drought events), more severe, and longer in duration(average increase of 8% for short-term droughts).Similarly, short-term agricultural droughts are projected to become more frequent(average increase of 28% in frequency of SSMI-3 drought events) but slightly shorter in duration(average decrease of 4%) in the future. Historically, drought propagation time from meteorological to hydrological drought is shorter than from meteorological to agricultural drought in most sub-basins. For the projected climate scenarios, the decrease in drought propagation time will likely stress the timing and capacity of water supply in the basin for irrigation and other uses.

关键词： Umatilla drought SPI SPEI SSI SSMI

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Parametric study on contact sensors for MASW measurement-based interfacial debonding detection for SCCS

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 331-344页

作者： Chen Hongbing Pang Xin Gan Shiyu Li Yuanyuan Gokarna Chalise Nie Xin Research Institute of Urbanization and Urban Safety School of Civil and Resource EngineeringUniversity of Science and Technology BeijingBeijing 100083China Department of civil Engineering Tsinghua UniversityBeijing 100084China Faculty of infrastructure Engineering Dalian University of TechnologyDalian 116081China

Steel-concrete composite structures(SCCS)have been widely used as primary load-bearing components in large-scale civil infrastructures.As the basis of the co-working ability of steel plate and concrete,the bonding status plays an essential role in guaranteeing the structural performance of SCCS.Accordingly,efficient non-destructive testing(NDT)on interfacial debondings in SCCS has become a prominent research area.Multi-channel analysis of surface waves(MASW)has been validated as an effective NDT technique for interfacial debonding detection for SCCS.However,the feasibility of MASW must be validated using experimental measurements.This study establishes a high-frequency data synchronous acquisition system with 32 channels to perform comparative verification experiments in depth.First,the current sensing approaches for high-frequency vibration and stress waves are summarized.Secondly,three types of contact sensors,namely,piezoelectric lead-zirconate-titanate(PZT)patches,accelerometers,and ultrasonic transducers,are selected for MASW measurement.Then,the selection and optimization of the force hammer head are performed.Comparative experiments are carried out for the optimal selection of ultrasonic transducers,PZT patches,and accelerometers for MASW measurement.In addition,the influence of different pasting methods on the output signal of the sensor array is discussed.Experimental results indicate that optimized PZT patches,acceleration sensors,and ultrasonic transducers can provide efficient data acquisition for MASW-based non-destructive experiments.The research findings in this study lay a solid foundation for analyzing the recognition accuracy of contact MASW measurement using different sensor arrays.

关键词： steel-concrete composite structures(SCCS) interface debonding detection multi-channel analysis of surface waves(MASW) sensor selection comparative experimental study

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Detection of internal crack growth in polyethylene pipe using guided wave ultrasonic testing

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 319-329页

作者： Jay Kumar Shah Hao Wang Said El-Hawwat Centre of Advanced infrastructure and Transportation RutgersThe State University of New JerseyNJ 08854USA Department of civil and Environmental Engineering RutgersThe State University of New JerseyNJ 08854USA

Despite the success of guided wave ultrasonic inspection for internal defect detection in steel pipes,its application on polyethylene(PE)pipe remains relatively unexplored.The growth of internal cracks in PE pipe severely affects its pressure-holding capacity,hence the early detection of internal cracks is crucial for effective pipeline maintenance strategies.This study extends the scope of guided wave-based ultrasonic testing to detect the growth of internal cracks in a natural gas distribution PE pipe.Laboratory experiments and a finite element model were planned to study the wave-crack interaction at different stages of axially oriented internal crack growth with a piezoceramic transducer-based setup arranged in a pitch-catch configuration.Mode dispersion analysis supplemented with preliminary experiments was performed to isolate the optimal inspection frequency,leading to the selection of the T(0,1)mode at 50-kHz for the investigation.A transmission index based on the energy of the T(0,1)mode was developed to trace the extent of simulated crack growth.The findings revealed an inverse linear correlation between the transmission index and the crack depth for crack growth beyond 20%crack depth.

关键词： polyethylene pipes internal cracks guided wave ultrasonic testing torsional modes finite element modeling

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Study of interfacial transition zones between magnesium phosphate cement and Portland cement concrete pavement

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第3期11卷 523-537页

作者： Fei Liu Baofeng Pan Changjun Zhou Ge Li Xiaocun Wang Jiaquan Li Faculty of infrastructure Engineering Dalian University of Technology Tongren City Transportation Bureau Beijing civil Aviation Design and Research Institute of China Design Group

The Portland cement concrete pavement(PCCP) often suffers from different environmental distresses and vehicle load failure, resulting in slab corner fractures, potholes, and other diseases. Rapid repair has become one of the effective ways to open traffic rapidly. In this study, a novel type of rapid repair material, basalt fiber reinforced polymer modified magnesium phosphate cement(BFPMPC), is used to rapidly repair PCCP. Notably, the mechanical properties and characteristics of the repair interfaces which are named interfacial transition zones(ITZs) formed by BFPMPC and cement concrete are focused on as a decisive factor for the performance of the rapid repair. The changing trend of the elastic moduli was studied by nanoindentation experiments in the ITZs with the deconvolution analysis that the elastic moduli of certain kinds of substances can be determined.The experimental results show that the elastic modulus of ITZ-1 with a width of about20 μm can be regarded as 0.098 times of the aggregate, and 0.51 times of the ordinary Portland cement(OPC) mortar. The BFPMPC-OPC mortar ITZ has roughly the same mechanical properties as the ITZ between aggregate and BFPMPC. A multi-scale representative two-dimensional model was established by random aggregate and a two-dimensional extended finite element method(XFEM) to study the mechanical properties of the repair interface. The simulation results show that the ITZ formed by the interface of BFPMPC and OPC mortar and basalt aggregate is the most vulnerable to failure, which is consistent with the nano-indentation experimental results.

关键词： Portland cement concrete pavement Interfacial transition zone Magnesium phosphate cement Repair interface Nanoindentation Mechanical properties and characteristics

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An Optimized System of Random Forest Model by Global Harmony Search with Generalized Opposition-Based Learning for Forecasting TBM Advance Rate

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Computer Modeling in Engineering & Sciences 2024年第3期138卷 2873-2897页

作者： Yingui Qiu Shuai Huang Danial Jahed Armaghani Biswajeet Pradhan Annan Zhou Jian Zhou School of Resources and Safety Engineering Central South UniversityChangsha410083China School of civil and Environmental Engineering University of Technology SydneyNew South WalesAustralia Centre for Advanced Modelling and Geospatial Information Systems School of Civil and Environmental EngineeringFaculty of Engineering and Information TechnologyUniversity of Technology SydneyNew SouthWalesAustralia civil and infrastructure Engineering discipline School of EngineeringRoyal Melbourne Institute of Technology(RMIT)MelbourneVictoria3001Australia

As massive underground projects have become popular in dense urban cities,a problem has arisen:which model predicts the best for Tunnel Boring Machine(TBM)performance in these tunneling projects?However,performance level of TBMs in complex geological conditions is still a great challenge for practitioners and researchers.On the other hand,a reliable and accurate prediction of TBM performance is essential to planning an applicable tunnel construction schedule.The performance of TBM is very difficult to estimate due to various geotechnical and geological factors and machine specifications.The previously-proposed intelligent techniques in this field are mostly based on a single or base model with a low level of accuracy.Hence,this study aims to introduce a hybrid randomforest(RF)technique optimized by global harmony search with generalized oppositionbased learning(GOGHS)for forecasting TBM advance rate(AR).Optimizing the RF hyper-parameters in terms of,e.g.,tree number and maximum tree depth is the main objective of using the GOGHS-RF model.In the modelling of this study,a comprehensive databasewith themost influential parameters onTBMtogetherwithTBM AR were used as input and output variables,respectively.To examine the capability and power of the GOGHSRF model,three more hybrid models of particle swarm optimization-RF,genetic algorithm-RF and artificial bee colony-RF were also constructed to forecast TBM AR.Evaluation of the developed models was performed by calculating several performance indices,including determination coefficient(R2),root-mean-square-error(RMSE),and mean-absolute-percentage-error(MAPE).The results showed that theGOGHS-RF is a more accurate technique for estimatingTBMAR compared to the other applied models.The newly-developedGOGHS-RFmodel enjoyed R2=0.9937 and 0.9844,respectively,for train and test stages,which are higher than a pre-developed RF.Also,the importance of the input parameters was interpreted through the SHapley Additive exPlanations(SHAP)method,and it was found that thrust force per

关键词： Tunnel boring machine random forest GOGHS optimization PSO optimization GA optimization ABC optimization SHAP

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Experimental investigation on the permeability of gap-graded soil due to horizontal suffusion considering boundary effect

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1072-1084页

作者： Xuwei Wang Yeshuang Xu State Key Laboratory of Ocean Engineering School of Naval ArchitectureOceanand Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Shanghai Key Laboratory for Digital Maintenance of Buildings and infrastructure Department of Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China

The boundary condition is a crucial factor affecting the permeability variation due to suffusion.An experimental investigation on the permeability of gap-graded soil due to horizontal suffusion considering the boundary effect is conducted,where the hydraulic head difference(DH)varies,and the boundary includes non-loss and soil-loss conditions.Soil samples are filled into seven soil storerooms connected in turn.After evaluation,the variation in content of fine sand(ΔR_(f))and the hydraulic conductivity of soils in each storeroom(C_(i))are analyzed.In the non-loss test,the soil sample filling area is divided into runoff,transited,and accumulated areas according to the negative or positive ΔR_(f) values.ΔR_(f) increases from negative to positive along the seepage path,and Ci decreases from runoff area to transited area and then rebounds in accumulated area.In the soil-loss test,all soil sample filling areas belong to the runoff area,where the gentle-loss,strengthened-loss,and alleviated-loss parts are further divided.ΔR_(f) decreases from the gentle-loss part to the strengthened-loss part and then rebounds in the alleviated-loss part,and C_(i) increases and then decreases along the seepage path.The relationship between ΔR_(f) and Ci is different with the boundary condition.Ci exponentially decreases with ΔR_(f) in the non-loss test and increases with ΔR_(f) generally in the soil-loss test.

关键词： Suffusion Permeability Experimental investigation Boundary effect Horizontal seepage

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Uncertainties of landslide susceptibility prediction: Influences of random errors in landslide conditioning factors and errors reduction by low pass filter method

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 213-230页

作者： Faming Huang Zuokui Teng Chi Yao Shui-Hua Jiang Filippo Catani Wei Chen Jinsong Huang School of infrastructure Engineering Nanchang UniversityNanchang330031China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu610059China Department of Geosciences University of PadovaPadovaItaly College of Geology and Environment Xi’an University of Science and TechnologyXi’an710054China discipline of civil Surveying and Conditioning EngineeringPriority Research Centre for Geotechnical Science and EngineeringUniversity of NewcastleNewcastleNSWAustralia

In the existing landslide susceptibility prediction(LSP)models,the influences of random errors in landslide conditioning factors on LSP are not considered,instead the original conditioning factors are directly taken as the model inputs,which brings uncertainties to LSP results.This study aims to reveal the influence rules of the different proportional random errors in conditioning factors on the LSP un-certainties,and further explore a method which can effectively reduce the random errors in conditioning factors.The original conditioning factors are firstly used to construct original factors-based LSP models,and then different random errors of 5%,10%,15% and 20%are added to these original factors for con-structing relevant errors-based LSP models.Secondly,low-pass filter-based LSP models are constructed by eliminating the random errors using low-pass filter method.Thirdly,the Ruijin County of China with 370 landslides and 16 conditioning factors are used as study case.Three typical machine learning models,i.***.multilayer perceptron(MLP),support vector machine(SVM)and random forest(RF),are selected as LSP models.Finally,the LSP uncertainties are discussed and results show that:(1)The low-pass filter can effectively reduce the random errors in conditioning factors to decrease the LSP uncertainties.(2)With the proportions of random errors increasing from 5%to 20%,the LSP uncertainty increases continuously.(3)The original factors-based models are feasible for LSP in the absence of more accurate conditioning factors.(4)The influence degrees of two uncertainty issues,machine learning models and different proportions of random errors,on the LSP modeling are large and basically the same.(5)The Shapley values effectively explain the internal mechanism of machine learning model predicting landslide sus-ceptibility.In conclusion,greater proportion of random errors in conditioning factors results in higher LSP uncertainty,and low-pass filter can effectively reduce these random errors.

关键词： Landslide susceptibility prediction Conditioning factor errors Low-pass filter method Machine learning models Interpretability analysis

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Construction of shallow buried large-span metro stations using the small pipe roof-beam method

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Frontiers of Structural and civil Engineering 2024年第1期18卷 122-136页

作者： Qian BAI Wen ZHAO Yingda ZHANG Pengjiao JIA Xiangrui MENG Bo LU Xin WANG Dazeng SUN School of Resources and civil Engineering Northeastern UniversityShenyang 110819China Centre for infrastructure Engineering and Safety School of Civil and Environmental EngineeringThe University of New South WalesNSW 2052Australia School of Rail Transportation Soochow UniversitySuzhou 215131China China Northeast Architectural Design and Research Institute Co. Ltd.Shenyang 110006China

In relation to the Shifu Road Station project on Line 4 of the Shenyang Metro in China,a small-pipe roof-beam method for constructing subway stations is presented.First,a numerical simulation was performed to optimize the supporting parameters of the proposed method and determine the design scheme.Subsequently,the deformation of the pipe roof and surface settlement during the construction process were investigated.Finally,the surface settlement attributed to the excavation was studied through field monitoring,and the proposed method was compared with other methods.The results show that an increase in the pipe-roof spacing has little effect on the surface settlement and piperoof deformation.The bearing capacity of the pipe roof can be efficiently utilized once the flexural stiffness reaches 2EI,and the flexural stiffness is not the dominant factor controlling the deformation.The essential stages in controlling surface settlement are the excavations of the transverse pilot tunnels and the soil between them.The final settlement value of the ground was 24.1 mm,resulting in a reduction in the construction period by at least five months while satisfying the control requirements.

关键词： subway station pipe-roof method surface settlement simulation on-site monitoring

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